7th International Symposium on Technetium
and Rhenium – Science and Utilization
July 4 -8, 2011, Moscow, Russia
BOOK OF PROCEEDINGSPUBLISHING HOUSE GRANITSA
MOSCOW 2011th

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

RUSSIAN ACADEMY OF SCIENCES,
IPCE RAS, MUCTR, ISTC, RFBR, RUSNANO, ROSATOM, ACADEMINVESTSERVICE, FMBC FMBA

7th International Symposium on
Technetium and Rhenium –Science and Utilization
July 4 -8, 2011, Moscow, Russia
BOOK OF PROCEEDINGS

Edited by
K.E. German, B.F. Myasoedov, G.E. Kodina, A.Ya. Maruk, I. D. Troshkina

Publishing House GRANITSA, MOSCOW 20111th

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

7th International Symposium on Technetium and Rhenium – Science and Utilization –BOOK OF PROCEEDINGS - July 4 -8, 2011, Moscow, Russia (Eds. K.E. German, B.F. Myasoedov, G.E.
Kodina, A.Ya. Maruk, I. D. Troshkina), Publishing Group Granica: Moscow, 2011, 461 p.

© IPCE RAS 2011
© RUSNANO 2011
© ISTC 2011
© ACADEMINVESTSERVICE 2011
© RFBR 2011
© GRANICA 2011

Publishing House GRANITSA, 2011
UDK 546.718 : 548.736
ISBN 978-5-94691-473-4

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CONTENTS :Openning ceremony:
B.F. Myasoedov Welcome address
K.E. German, F. Poineau. Technetium: new trends in investigation and application
E.N. Kablov, N.V. Petrushin, V.V. Sidorov. Rhenium in nickel-base superalloys for
single crystal gas turbine blades
M.Ozawa. ISTR Retrospectives and Prospects - in view points of Nuclear Fuel Cycle
Session 1. Fundamental Physics and Chemistry of Tc and Re
T. Yoshimura, C. Suo, S. Ishizaka, A. Ito, E. Sakuda, A. Shinohara, N. Kitamura.
Spectroscopic and photophysical properties of chalcogenide-capped octahedral
hexarhenium complexes with N-heteroaromatic ligands
Y.V. Mironov, S.S. Yarovoi, K.A. Brylev, V.E. Fedorov. Rhenium octahedral
chalcohydroxo cluster complexes
F. Poineau, A. P. Sattelberger, B. L. Scott, P. Forster, Ph. Weck, E. Johnstone,K. R.
Czerwinski. Technetium halides: from molecular to extended structures
E.N. Pryamilova, O.V. Chernyshova, D.V. Drobot. Synthesis of rhenium alkoxides via
anodic dissolution
Th. Gerber, K. Potgieter, P. Mayer. Rhenium coordination chemistry: old ligands die
hard.
T.Kobayashi, X.Gaona, D.Fellhauer, M. Altmaier. Redox behaviour of the
Tc(VII)/Tc(IV) couple in diluted NaCl solution in various reducing systems
A.E. Miroslavov, G.V. Sidorenko, A.A. Lumpov, D.N. Suglobov, M.S. Grigor’ev, V.V.
Gurzhii. Technetium(I) hexacarbonyl cation and its reactivity
G.V. Sidorenko, A.E. Miroslavov, D.N. Suglobov, M.S. Grigor’ev,V.V. Gurzhii.
Structural Chemistry of Technetium Carbonyl Compounds
D.V. Drobot, O.V. Chernyshova, O.S. Kriyzhovets, K.A. Smirnova, I.V.Masilin, A.V.
Shevelkov, M.V. Tsodikov, A.V. Chistyakov, O.V.Petrakova, E.G. Il’in. “Soft”
chemistry methods appear as an effective way for production of superdispersive (nanosized) materials based on Re and d-elements of V-VIII groups
C. Kremer, R. Chiozzone. Structure and magnetic properties of polynuclear complexes
containing Re(IV)
A.I. Irtegov, M.A. Kurykin, V.N. Khrustalev, E.E. Nikishina, D.V. Drobot.
Polyfluorinated β-diketonates of rhenium
W.M. Kerlin, T. Yordanova, F. Poineau, P.M. Forster, A.P. Sattelberger, K.R.
Czerwinski. Preparation of technetium metal-metal bonded acetate dimers via
hydrothermal route
Povarova K.B. Physicochemical principles of the development of rhenium-based andrhenium-containing alloys
E.V. Johnstone, F. Poineau, P.F. Weck, E. Kim, P.M. Forester, B. Scott, T. Hartmann,
A.P. Sattelberger, K.R. Czerwinski. Synthesis and characterization of low-valent binary
technetium chlorides
V.E. Fedorov, Yu.V. Mironov, N.G. Naumov, K.A. Brylev. Recent results in rhenium
cluster chemistry
O.S. Kriyzhovets, D.V. Drobot, A.V. Shevelkov, O.V. Petrakova. Heteroligand
alkoxides of rheniumcontaining O-Et and O-iPr ligands
A.A. Aminjonov. Status and prospects of studies on the chemistry of coordination
compounds of rhenium(V)
N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjоnov Effect of the rhenium(V)complex of 3,4-dimethyl-1,2,4-triazol-5-thiol on the diacetate cellulose light fastness
A.V. Ermolaev, A.I. Smolentsev, K.A. Brylev, V.E. Fedorov, Y.V. Mironov.
Octahedral rhenium(III) chalcocyanohydroxo cluster complexes

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M.V. Sukhanov, V.I. Pet'kov. Technetium and Rhenium Orthophosphates with
Kosnarite-Type Structure
A.Yu.Didyk, V.S.Kulikauskas, R. Wiśniewski. Depth distribution of D-ions with 25
keV energy implanted into pure Mn, Tc* and Re foils up to high fluencies (1÷2)×1018
D+/cm2, measured by ERD method
Z.Ch.Kadirova, Kh.T. Sharipov, Sh. Juraev, N.A. Parpiev. Coordination compounds of
biologically active N-containing heterocyclic ligands
N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjonov . Chelation of rhenium (V) with
3-ethyl-4-methyl-1,2,4-triazol-5-thiol in 3 M HCl medium
K.S. Mabatkadamova, N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjonov
Complexation in the system Re (V) – 1-methyl-2-merkaptoimidazolE – 8 mol/l HCl
F. Poineau, I. Denden, R. Essehli, K. German, K. Czerwinski and M. Fattahi.
Speciation of Tc in sulfuric media. Effect of -radiation from Arronax Cyclotrone
A. Ya. Maruk, M. S. Grigor’ev, K. E. German. Synthesis, Crystal Structure andProperties of Triphenylguanidinium Tetraoxidorhenate Hemihydrate
A.M. Fedosseev, M.S. Grigoriev. Synthesis and crystal structure of[AnO2(HMPA)4](MO4)2 (An = U, Pu; M = Cl, Tc, Re)
K.E. German, A.Ya. Maruk, F. Poineau, P.Weck, G.A. Kirakosyan, V.P. Tarasov, K.
Czerwinski, A. Sattelberger. Transformation of Тс(VII) in acids: TcO3(OH)(H2O)2 andTcO3(H2O)3+ in HClO4 and polymeric species in solids and acetonitryle solutions
I.M. Gayfulin, Yu.V. Mironov, A.I. Smolentsev. New compounds based on the cluster
anions [Re4Q4(CN)12]4- (Q=S, Se, Te) and cations (1,10-phenH) +, Nd3+, Er3+
A.A. Aminjonov. Mutual substitution of ligands in complex compounds of rhenium(V)Fathi Habashi. Rhenium and its position in the periodic table
G.V. Kolesnikov, V.N. Khrustalev, K.E. German, I.G. Tananaev, G.A. Kirakosyan,
E.A. Katayev. Macrocyclic receptors for pertechnetate and perrhenate anions
Session 2. Tc in the Nuclear Fuel Cycle and in the Environment. Analytical
Chemistry of Tc and Re
M. Ozawa, T. Suzuki, S. Koyama, Y. Fujii, M. Saito. How to manage technetium(nuclear rare metal) and actinides, towards future reprocessing system providing nonproliferetion
Т. Boytsova, V. Korolev, Y. Pokhitonov, V. Babain, М. Ozawa, Т. Suzuki. Combined
separation of Pd and Tc from the raffinates of the spent nuclear fuel reprocessing
А.А. Kozar’, V.F. Peretrukhin, K.V. Rotmanov, V.A. Tarasov. The elaboration oftechnology bases for the artificial stable ruthenium preparation from technetium-99
transmutation products
K.E. German, Ya.A. Obruchnikova, D.N. Tumanova, V.F. Peretrukhin, Ph. Moisy.
Technetium catalytic effect and speciation in nitric acid solutions in presence of Np(V),
Th(IV) and Zr(IV) and reducing nitrogen derivatives
D.N. Kolupaev, A.B. Melentev, A.N. Mashkin, V.A. Misharin, A.V. Ananyev, V.P.
Shilov, K.E. German, I.G. Tananaev. Composition and catalytic properties oftechnetium-based sediments and interphase substances found in the uranium-plutonium
separation stage of the PUREX process
T.V. Khijniak. Interaction of microorganisms and radionuclides
S.N. Britvin, Y.I. Korneyko, S.V. Krivovichev, W. Depmeier. Layered hydrazinium
titanate : reductive adsorbent for irreversible immobilization of technetium
S.V. Yudintsev, E.E. Konovalov, B.S. Nikonov. Re and Tc in cermets waste forms
M. Chotkowski, A. Czerwiński. Electrochemical and spectroelectrochemical
investigations of TcO4- electroreduction in acidic media
L.V.Borisova, V.V.Minin. Stabilization of rhenium (VI) compounds in solution andusing them in analysis
A.A.Grechnikov, L.V.Borisova, V.A.Ryabukhin. Novel approach to the mass-

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spectrometric determination of trace amounts of rhenium using its complexes withorganic reagents
K. Leszczynska-Sejda, G. Benke, K. Anyszkiewicz, A. Chmielarz, S. Cupial. Method
for hexamminecobalt (III) perrhenate synthesis from perrhenic acid
D. Golovanov . Modern X-ray analytical instruments of Bruker AXS
R.A. Aliev. Preparation of 95m,gTc, 96Tc by irradiation of molybden with ALPHAparticles and deutrons
S. Alwaer. Modernization method for production of Fission Mo-99 from LowEnriched-Uranium Foil (LEU-Foil)
А.А. Kozar’, V.F. Peretrukhin. 99Tc transmutation target heterpgenity for the artificial
stable ruthenium purification from 106Ru
G.S. Bulatov, K.N. Gedgovd, D.Yu. Lyubimov. The behavior of technetium, americium
and neptunium in the spent FBR (U,Pu)N fuel after fast neutron irradiation as a functionof the temperature and burn-up
E. Pichuzhkina, S. Tomilin. Compounds of Curium with Technetium
V.I. Volk, K.N. Dvoyeglazov, V.L. Vidanov, L.N. Sergeeva. Extractionchromatographic purification of uranium extract from technetium
E.Е. Konovalov, Т.О. Мishevets, S.S. Shulepov, Yu.D. Boltoev. Metal-thermal
Immobilization of High-active Technetium Waste into Matrices Based on Metal Glass
Crystalline Composites
N.N. Popova, G.L. Bykov, I.G. Tananaev, B.G. Ershov. Application of modified woodmaterials for extraction of technetium(VII) from aqueous medium
K.E. German, A.B. Melentev, Ya. V. Zubavichus2, S.N. Kalmykov3, A.A. Shiryaev,
I.G. Tananaev. Structure and properties of insoluble Technetium compounds formed inTechnetium - Hydrazine - DTPA -nitric acid- solutions
A.B. Melentev, A.N. Mashkin, O.V. Tugarina, K.E. German, I.G. Tananaev. The
behavior of the technetium - hydrazine - nitric acid - TBP system in presence of thecomplexing agents
A.M. Safiulina, K.E. German, E.I. Goryunov, I.B. Goryunova, E.E. Nifantiev, I.G.
Tananaev, B.F. Myasoedov. Technetium(VII) extraction with hybrid phosphornirogenated derivative ligands
M.K. Abdulahatov, S.A. Bartenev, M.J. Goikhman, A.V. Gribanov, V.S. Gusel'nikov,
M.P. Zykov, J.N. Novikov, J.N. Sazanov, N.G. Firsin. New materials forimmobilization of technetium-containing waste for the purpose of their isolation fromthe environment
German K.E., Peretrukhin V.F., D.N. Tumanova, A.Yu. Tsivadze. Technetium sulfides– role in chemistry and ecology
K.E. German, T. V. Khijniak, V.F., Peretrukhin . Technetium limnology as frame forits ecology and the key for underground storage
Yu.I. Korneyko, V.M. Garbuzov, B.E. Burakov. Kassiterite as a Durable Host-Phase
for Technetium Immobilization
A.G. Maslennikov, K.V. Rotmanov, N.G. Kravchenko, V.M. Radchenko, M.V.
Kormilitsyn, V.F. Peretrukhin. Electrochemical Investigation of Corrosion andDissolution of Metallic Technetium and Tc-Ru Alloys in 0,5 – 6,0 M HNO3
R.A.Aliev, S.N. Kalmykov, I.G. Tananaev, I.A.Ivanov. Tc-99 determination incontaminated groundwater
O. Batuk, S.N. Kalmykov, E.V. Zakharova. Sorption of Tc-99 and Np-237 by depleted
UO2
Yu.I. Urusov, K.E.German, A.V.Kopytin, A.F.Zhukov. ReO4- and TcO4- ion-selective
bubble-through flow cells
Session 3. Re Hydrometallurgy
I. D. Troshkina. Rhenium in Nuclear Fuel Cycle

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Z.S. Abisheva, A.N. Zagorodnyaya. Rhenium of Kazakhstan
E.А. Ospanov, E.I. Gedgagov, N.A. Ospanov, S.V. Zakharyan. Development of thetechnology for production of high-purity ammonium perrhenate at Balkhash copper
smelter, Republic of Kazakhstan
E.I Gedgagov, Nekhoroshev N.E. Use of ion-exchenge resins for production of highpurity ammonium perrhenate when processing rhenium-containing ore and secondary
raw material
M. Mikhaylenko, Purolite® ion exchange resins for recovery and purification ofrhenium
O. Bozhkov, Ch. Tzvetkova, L. Borisova. Phytomining of Re - an Alternative Method
for Re Production
V.P. Volkov, N.M. Mescheryakov. Sorptive Recovery of Rhenium from Circulating
Solutions of Uranium in Situ Leaching Operation at Navoi GMK, Uzbekistan
A.G. Kasikov, A.M. Petrova. Rhenium(VII) solvent extraction by mixtures of tertiaryamine and oxygen-containing extragents from sulphate media
A.N. Zagorodnyaya, Z.S. Abisheva, S.E. Sadykanova. Interphase Substances ofRhenium Extraction Circuit are a source for production of rhenium and radiogenic
osmiumL. Ya. Agapova, Z. S. Abisheva, S. K. Kilibayeva, I. A. Sapukov. Electrodeposition ofrhenium alloys in form of powders and coatings from water solutions by membraneelectrolysis
Z.S. Abisheva, L.Ya. Agapova, E.I. Ponomareva, Z.T. Abdrakhmanova Application ofelectrodialysis method for high purity metal rhenium obtaining
E.A. Salahova, V.A. Majidzade, F.S. Novruzova, A.F. Qeybatova, P.E. Kalantarova.
The electrolytic subsidence of rhenium from acid electrolytes
A.A. Blokhin, E.E. Maltseva, М.А. Pleshkov, Ju.V. Murashkin, M.A. Mikhaylenko.
Sorption recovery of rhenium from acidic sulfate and mixed nitrate-sulfate solutions
containing molybdenum
Ch. Tzvetkova, O. Bozhkov, L. Borisova. Rhenium Phytomining by Alfalfa(Medicago) from soils of ore dressing regions at laboratory conditions
A.G. Kasikov, A.M. Petrova, N.S. Areshina, A.A. Blokhin, E.E. Maltseva. Rhenium
recovery from gas-purification wastes of THE Kola mining Company
A.G. Kasikov, A.M. Petrova. Solvent extraction of rhenium(VII) from acid solutions
with high-molecular aliphatic alcohols
A.A. Palant, O.M. Levchuk, A.M. Levin, O.V. Reshetova. Production of the highpurity NH4ReO4 using electrodialysis method
R.D.Allabergenov, Kh.T.Sharipov, R.Kh.Sharipov, A.A.Niyazmatov. Regularities ofRhenium Salts Oxidizing Leaching
I.D.Troshkina, A.V.Shilyaev, N.V.Balanovskiy, A.M.Chekmarev, О.А. Chernyadeva.
Rhenium Sorption from Uranium-Containing Solution by Nanostructured Ionites
A. A. Abdusalomov, I. D. Troshkina, A. M. Chekmarev, N. P. Ismailov. Sorption of
palladium from the rhenium containing sulfuric acid solution
I. D. Troshkina, T. G. Abdrakhmanov, N. A. Smirnov, A. B. Mayboroda, K. I.
Potapova, A. M. Chekmarev. Ultrafiltration Separation of Rhenium and Uranium Using
Nitrogen-Containing Polyelectrolytes
I.D. Troshkina, L.A. Zemskova, A.M. Chekmarev, A.V. Plevaka, Aye Minn, A.V.
Shilyaev, A.V. Voit, D. N. Tumanova. Recovery of Rhenium from Aqueous Solutions
by Fibrous Materials
A.G. Kasikov, A.M. Petrova, P.B. Gromov, V.T. Kalinnikov. Rhenium recyclingfrom heat-resistant rhenium-containing nickel-based superalloys
A.M. Safiulina, K.E. German, N.N. Popova, M.Yu. Burtsev. Installation for liquidliquid extraction concentrating and recovery of Rhenium from aqueous sulfate solution

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I. D. Troshkina, M.V. Vazchenkov, A. M. Chekmarev. Recovery of rhenium from oil
shale
Session 4. Tc and Re in Nuclear Medicine
G.E.Kodina. Tc-99m and Re-188 in Russian Nuclear Medicine
H. Braband. The fac-{TcO3}+ core – a challenge for high-valent technetium chemistry
A.Ya. Maruk, A.B. Bruskin, G.E. Kodina. New radiopharmaceuticals based ontechnetium-99m with bifunctional chelating agents
V.N. Korsunsky, V.N. Oshchepkov, S.V. Shiryaev, E.Z. Rabinovich. “Rezoskan,
99m
Tc” in the diagnosis of metastatic bone lesions
V.S. Skuridin, V.L. Sadkin, E.S. Stasiuk, N. V. Varlamova, A.C. Rogov, E.A.
Nesterov. Obtaining Technetium-99m Labelled Nanocolloides Based on Aluminium
Oxide for Medical Diagnostics
E.A. Nesterov, V.S. Skuridin, M.L. Belyanin, J.V. Nesterova, V.L. Sadkin, A.S. Rogov,
I.V. Chikova. Receiving of nanosized colloids based on modificated DTPA moleculelabeled with technetium-99m
N.I. Gorshkov, A.Yu. Murko, Yu.I. Zolotova. O.V. Nazarova, I.I. Malakhova,
V.D.Krasikov, R. Schibli. Synthesis and complex analysis of biologically active
polymers (poly-N-vinylpyrrolidone) with Re(CO)3species
A.N. Klyopov, V.V. Krylov, Y.A. Kurachenko, Eu.S. Matusevich, Eu.V. Snigirev, O.P.
Aleksandrova. Development of dosimetric support and planning of radionuclide therapy
with radiopharmaceutical labeled 188Re
A. Hammadi. Education and training in nuclear medicine, radiopharmacy, medical
physics and molecular imaging: the INSTN experienced approach
M.L. Bonardi, F. Groppi, E. Lapshina, S. Manenti, L. Gini. High Specific Activity
Radionuclides IN NCA FORM: Re-186g produced by Cyclotron
M.P.Zykov, A.T.Filyanin, G.E.Kodina, A.Yu.Tsivadze, V.N. Romanovsky,
D.A.Tkachuk, O.A.Filyanin, S.P.Orlov, V.A.Novojilov. Optimization of parameters of
the 188Re obtaining process in a centrifugal extractor
A.A. Semenova, N.G. Baranov, D.V. Stepchenkov, E.V. Sulim, V.M. Petriev.
188
W/188Re generator production technology for nuclear medicine
N.G. Baranov, D.V. Stepchenkov, N.A.Nerozin, E.V. Sulim, Yu.V.Minko,
А.А. Semenova. Substantiation of Engineering Parameters of a Rhenium-188
Stationary Generator for Radionuclide Therapy
A.N. Klyopov, V.M. Petriev, V.G. Skvortsov, V.V. Kanygin, V.K. Shiryaeva, O.P.
Aleksandrova. Mathematical models for pharmacokinetics and dosimetry inexperimental radiobiological researches of bone-seeking radiopharmaceutical 188ReKOEDF
N.D. Betenekov, E.I. Denisov, L.M. Sharygin, M.N. Golubev. The generator 99mTс
based on inorganic sorbent “Thermoxide-5”
V.Е. Baulin, Kovalenko O.V., Usolkin A.N., Voroshilov Y.A.. Yakovlev N.G.,
Tsivadze A.Yu. Investigation of the sorbents on the basis of the new phosphorylcontaining ligands for allocation, concentration and purification of the molybdenum
from the irradiated uranium targets
L. Fuks, E. Gniazdowska, P. Kozminski. Novel technetium and rhenium complexes
with the N-heterocyclic aldehyde thiosemicarbazones - potential radiopharmaceuticals
E. Gniazdowska, P. Kozminski, K. Bankowski. 99mTc-labelled vasopressin analogd(CH2)5[D-Tyr(Et2),Ile4,Eda9] a vp as a potential radiopharmaceutical for small-cell lungcancer (SCLC) imaging
А.О. Malysheva, G.E. Kodina, О.Е. Klementyeva. Complexes of technetium-99m andrhenium-188 with zoledronic acid in nuclear medicine
V.G. Merkulov, E.V. Chibisov, V.V. Zukau, Yu.S. Maslennikov, G.G. Glukhov
Production of 188W and extraction of 188Re at IRT-T

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D.V. Stepchenkov, N.A. Nerozin, Baranov N.G., Sulim E.V., Semenova A.A.
Technetium-99m Generator Production and Application Experience
N.B. Epstein, G.M. Khomushku, L.D. Artamonova, V.G. Skvortsov. Determination of
ascorbic acid in kit by high-performance liquid chromatography
N. S. Al-Hokbany, I. J. Al-Jammaz. Synthesis and characterization complex of the{ReO}3+ core with SN and N donor ligands
N. Taratonenkova, A. Malysheva, G. Kodina, O. Klementieva. Preparation andbiological study of «Nanotech, 99mTc»
Y.N. Reshetnik, Bykov A.N., Kodina G.Е., Malysheva A.O. Sorption removal of
Na99mTcО4 from extracts of extraction generator 99Mo/99mTc
Session 5. Applications of Tc and Re in technology, including their alloys inModern Constructing Materials
B.D. Bryskin, E.D. Sayre. The fabrication development of rhenium used in hightemperature rockets and high temperature space power reactor
T. Leonhardt, J. Ciulik.Making and Shaping of Rhenium and Rhenium Containing
AlloysI.V. Mazilin, D.V. Drobot. Heterometallic Rhenium, Nickel, Co-alkoxides asprecursors for functional materials synthesis
A.P. Parshin, R.N. Manuylov, S.A. Melnikov, G.M. Voldman. Metallothermic method
for producing rhenium-based alloys
F. Morito, M.I. Danylenko, A.V. Krajnikov. Rhenium effect in Mo-Re welds
P.P.Oleynikov, P.A.Zaytsev, A.A.Ulanovskiy, S.N.Nenashev, T.Ju.Goncharuk..Use ofTungsten and Rhenium Alloys for Manufacturing of High-Temperature Thermocouples
W5%Re/W20%Re
Povarova K.B, Kazanskaya N.K. Modern structural materials based on the WMo-Re system
E.D. Sayre. Technetium – a Rare Metal Produced by Man for Structural and Medical
use
N.S. Beknazarova, A.A. Aminjonov. Influence of oxochloro-thiopyrine rhenium(V)complex on radiation firmness of cellulose diacetate
I.G.Roberov, N.B.Gorina, G.S.Burkhanov. Plastic deformation of rhenium andplatinum-group metals
Session 6. Tc and Re nanotechnology and applications in the field of nanomaterials
Ya.V. Zubavichus, A.A. Veligzhanin, A.A. Chernyshov, E.V. Guseva. Synchrotron
diagnostics of functional nanomaterials
A.I. Kostylev, U.G. Pokrovskiy, I.D. Troshkina, N.G. Firsin, A.M. Chekmarev
Manufacture of nano- and ultradisperse powders of rhenium and refractory metals fromtechnogenic raw materials
N.R. Antipkin, G.A. Biljalova, M.A. Bogorodskaya, A.O. Bogorodsky, A.B. Sazonov,
A.S. Chagovets Non-stoichiometric synthesis of rhenium heptasulfide hydrosol
K.A. Smirnova, D.V. Drobot, A.I. Lvovskiy, O.V. Petrakova.
Controlled synthesis of ultra dispersed (nano sised) Rhenium oxides (IV) and (VI):synthesis of precusors and properties of the materials
G.V. Sidorenko, A.E. Miroslavov, D.N. Suglobov, A.A. Lumpov, A.N. Yalfimov.
Volatile technetium carbonyl compondsand prospects for their application
E.V. Abkhalimov, B.G. Ershov. Synthesis and characterization of Ni-M (M = Pd, Pt)
nanoparticle pair structures
R.D. Solovov, P.A. Morozov, B.G. Ershov. Pd nanoparticles in aqueous solutions:
synthesis and properties
V.Yu. Murzin, Ya.V. Zubavichus, M.V. Chukalina, A.A. Shiryaev, K.E. German.
Wavelet analysis of EXAFS spectra as applied to polynuclear and cluster transition
metal complexes

352
355
356
369
373
374
375
379
380
386
387
388

394
395
400
407
408
409
411

416
422

426
427
428
429

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A.A. Shiryaev. Nanodiamonds for biomedical and sorption applications: structure anddefects
Tananaev I.G., K.E. German. Nanotechnologies in radiochemical technology andradioecology including technetium speciation and separetions
G.S. Bulatov, K.N. Gedgovd, D.Yu. Lyubimov. High temperature interaction ofrhenium, molybdenum and tungsten metals with uranium mononitride
A.M. Fedosseev, A.A. Bessonov, Ph. Moisy. Thermal behavior of perrhenate complexesof Neodymium and preparation of nanodimensial rhenium cermetes
Ya.A. Obruchnikova, A.A. Shiryaev, A.M. Safiulina, A.V. Karpukhin, I.I. Kulakova,
K.E. German. Technetium(VII) sorption by modified nanodiamonds from aqueous andnitric acid solutions
K.E. German, M.S. Grigoriev, A.Ya. Maruk, Ya. V. Zubavichus, V.Yu. Murzin, Ya.A.
Obruchnikova, A.A. Shiryaev. Stabilization of nano-rhenium and nano-technetium in
amorphous carbon matrix
A.V. Kopytin, Yu. A. Politov, E.G. Ilyin, Yu.I. Urusov, K.E.German. Ion selective
electrodes based on monocrystalline KTiOPO4 with nanocapillar conductivity for
determination of K+-ions
Yu.V.Plekhanov, K.E.German. Quantum chemical study of subnanodimentional mixed
clusters of technetium and ruthenium
G.V. Sidorenko, A.E. Miroslavov, and D.N. Suglobov. Deposition of technetium
coatings by thermolysis of volatile carbonyl compounds

434
435
437
438
439

440

445

450
451

Session 7. ROUND TABLE: Tc and Re as buiseness projects Axial presentation: 452
Timofei Petrov: Introduction of innovative Russian radionuclide pharmaceuticals into 453
the local and global markets
Author index

455

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LOCAL SCIENTIFIC COMMITTEE

B.F. Myasoedov
A.Yu. Tsivadze
E.N. Kablov
A.I. Nikolaev
G.I. Burhanov
A.M. Chekmarev
B.G. Ershov
I.G. Tananaev
K.E. German
I.D. Troshkina

IPCE RAS, Moscow – Chairman
IPCE RAS, Moscow - Co-Chairman
VIAM, Moscow
ICTREMRM KSC RAS, Apatity
IMET RAS, Moscow
Mendeleev MUCTR, Moscow
IPCE RAS, Moscow
IPCE RAS, Moscow
IPCE RAS, Moscow - Co-Chairman, Secretary
Mendeleev MUCTR, Moscow - Co-Secretary (ReSection)

V.N. Andreev
А.А. Blokhin
A.V. Bychkov

IPCE RAS, Moscow
SPBSPU, St.-Petersburg
IAEA, Vienna

D.V. Drobot

Lomonosov MITHT, Moscow

A. A. Belova
K.N. Frolov
E.I. Gedgagov

RUSNANO, Moscow
RUSNANO, Moscow
GINTSVETMET, Moscow

M.S. Grigoriev
M.V. Kormilitsyn
A.A. Kasikov
G.E. Kodina
D.N. Kolupaev
L.N. Kolomiets
Е.G. Kudryavtsev
V.A. Lebedev
A.E. Miroslavov
A.A. Palant
V. F. Peretrukhin
K.B. Povarova
G.A. Sarychev
V.I. Volk

IPCE RAS, Moscow
NIIAR, Dimitrovgrad
ICTREMRM KSC RAS, Apatity
Burnazyan FMBC FMBA, Moscow - Co-Secretary
PA “Mayak”, Ozyorsk
IPCE RAS, Moscow
ROSATOM , Moscow
IPCE RAS, Moscow
Khlopin Radium Institute, St.-Petersburg
IMET RAS, Moscow
IPCE RAS, Moscow
IMET RAS, Moscow
VNIIHT, Moscow
Bochvar VNIINM, Moscow

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INTERNATIONAL ADVISORY COMMITTEE
Honorary Chairman - B.F. Myasoedov (Russia)
Chairman –K.E. German (Russia)
Chairman –T. Sekine (Japan)
R. Alberto(Switzerland)
B. Bryskin(USA)
K. Czerwinski(USA)
J. R. Dilworth(England)Y. Fujii(Japan)T.I.A. Gerber(South Africa)
G.E. Kodina(Russia)Ph. Moisy(France)M. Ozawa(Japan)V.F. Peretrukhin(Russia)
A. Sattelberger(USA)
I.D. Troshkina(Russia)
A.Yu. Tsivadze(Russia)F. Poineau(USA)
Contacts :Co-Chairman
K.E. German, IPCE RAS
Phone: +7 (495)335-2004; Fax: +7 (495)333-8522;
e-mail: istr2011@mail.ru; german@ipc.rssi.ru
Co-Chairman
T.Sekine, Tohoku University
Senday, Japan
Scientific secretary
I.D. Troshkina, MUCTR (Rhenium Section)
Phone: +7(495)496-7609; Fax: +7(495)490-7523;
e-mail: tid@rctu.ru.
Scientific secretary
G.E. Kodina, FMBC FMBA (Section of Nuclear Medicine)тел. +7(499)193-0188
e-mail: gkodina@yandex.ru

Web site: www.technetium-99.ru

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ISTR2011 REGISTRATION DESK

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Acad. B.F. Myasoedov welcome the ISTR2011 delegates.
WELCOME ADDRESS
On behalf of the International Advisory Committee and the Local Organizing and ScientificCommittee, we are honored and pleased to welcome you at the 7-th International Symposium on
Technetium and Rhenium –Science and Utilization . The Symposium is held on the 4-8 July 2011
in the principle building of the Presidium of Russian Academy of Sciences under the auspices of the
Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences,
Interdisciplinary Council on Radiochemistry at RAS and State Corporation ROSATOM,International Sciences and Technology Center, Japan Atomic Energy Agency, University of Nevada(USA), the Mendeleev Russian Chemistry Community, the Russian Nuclear Society, the DIAMEDltd, Purolyte ltd, Bruker ltd., Academinvestservice Ltd., Farmsintez Ltd. and others. Our intention is
to collect here the multidisciplinary investigator community in the field of technetium and rhenium
sciences and utilization both oriented to the development of nuclear chemistry, newradiopharmaceuticals and non-radioactive sciences and industry, ecology and metallurgy for mutual
coordination of the research efforts. The Symposium approaches the multidisciplinary issues related
to the development of state-of-art and production of new technologies in Tc and Re, throughout thecomparison of their properties, common in view of Periodic Table to validate their utilization.
Moscow is the perfect location for the Symposium. This city, being the capital of Russia, hasrecently got new pulse for development. It is also the artistic and cultural capital of Russia wellknown for its hospitality.Frumkin Institute of Physical Chemistry and Electrochemistry of Russian
Academy of Sciences, with its high professionalism and competence, will take care of the logistics
and hospitality during the Symposium. We are happy welcoming you in Moscow!
Academician Boris F. Myasoedov
Academician Aslan Yu. Tsivadze
Konstantin E. German
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A.Yu.Tsivadze, B.F. Myasoedov, A.M. Chekmarev, B. Bryskin

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TECHNETIUM: NEW TRENDS IN INVESTIGATION AND APPLICATION
K.E. German1, F. Poineau2
1

Frumkin Institute of Physical Chemistry and Electrochemistry of RAS (Moscow, Russia)
2
University of Nevada LasVegas (Las Vegas, USA)

Technetium has a noble history of scientific community research efforts with different
periods characterized by the principle interest sliding from broad general chemistry to nuclear
medicine, ecology, transmutation etc...[1-3]. Great efforts in elaboration of Tc separation
technology resulted in production of more than 1 kg of technetium in form of KTcO4 and someabout 0.5 kg of technetium in metallic state [4] in IPC AN USSR (ex-IPCE RAS). This quantity
was distributed in between the institutions of MINATOM and USSR Academy of Sciences in 1976
– 1982 providing extensive scientific researches. Many Tc applications having been considered atthat time including battery production, standard radiosurce production, ophtalmoapplicators,
defectoscopes etc. all these being based on the Tc metal foil produced by Oleg Balakhovsky (Fig.
1).

Fig. 1. Oleg Balakhovsky demonstrating the effect of Tc foil radiation
onto the electroscope discharge.
Finally the production of Tc was organized in USSR and by the 1986 year more than 100 kg
of Tc was separated from the spent nuclear fuel reprocessing solutions. The Chernobyl accident was
the evident reason for the refocussing of the researches from nuclear applications to the15

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011environmentally faced studies. The IPCE RAS was also engaged in these new research efforts that
determined the investigation subjects for the 1990-2000 decade.
Surprisingly we could note that the last years are marked with the return to broadly
understood general chemistry. This is evidently due to the improvement of the research
investigating methods, now making possible to readdress the questions that were waiting the answer
for many decades.
It is worth recalling the main gaps in Tc chemistry and thermodynamics having been
indicated in 1999 [1]. Joseph A. Rard (Fig.2) and co-authors have summarized the most important
information needed to improve the quality of the technetium thermodynamic data base for the safetyassessment of nuclear waste disposal. These items included some questions of Tc metal state,numerous oxides (also mixed-valent oxides), protonation constants for the formation ofundissociated pertechnetic acid, TcO3(OH)(aq) or HTcO4(aq) and its genesis in acids, numerous
inconsistence of solubility measurements (TcO2 (s), TcS2 (s), Tc2S7 (s), etc.) and the properties of
TcF6 (s).

Fig. 2. Joseph Rard (left) is perfect demonstrating [1]:Tc chemistry is not just a kitchen but also chemical thermodynamics (Oarai, Japan – 2005)
Some of these were tried to be answered during the last decade and reviewed in this work.
Important progress was obtained in nano-disperse Tc metal structure and properties and its
dependence on the carbon impurity present [2-3]. Better understanding of Tc sulfides and theirsolubility was due to a combination of ultramicrocentrifugative speciation and EXAFS
spectroscopic structure determination [4-5]. Another improvement gained for Tc(VII) species
including TcO3+ and pertechnic acid evolution was due to both synthetic and spectroscopic (TcNMR and EXAFS) studies [6-7].
It’s worth mentioning that a huge part of technetium chemistry mostly of radiopharmaceutical value
was systematically discussed at the TERACHEM International Symposiums serie having been
conducted by Prof. U. Mazzi and his colleagues (the latter hold in Bressanone in 2010 (Fig.3).

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Prof. U. Mazzi while organizing the tour to Dolomites for TERACHEM 2010 delegates
Very indicative for metal carbide and many other substance analyses are the implementations ofwavelet ideas for the EXAFS results treatment that are also discussed at ISTR2011 [8]. It is alsointeresting to note that even some simple binary compounds of Tc are still to be discovered:synthesis, spectroscopic and structural characterization of several new technetium binary halides,
including TcCl2, TcCl3, TcBr3 and TcBr4 and the formation mechanism of these new halides waspresented and discussed at this Symposium [9,10].Application of Tc was critically reconsidered,with huge interest to be paid to Tc transmutation into stable Ru-100. Anyhow some other new
applications were focused with the attempts providing direct usage of Tc radioactivity.
References.
1. Rard, J.A., Rand, M.H., Andregg, G., Etc. Chemical Thermodynamics, Vol. 3. Chemical
Thermodynamics of Technetium (M.C.A. Sandino and E. Östhols, eds.), OECD Nuclear Energy
Agency, Data Bank, Issy-les-Moulineaux, France 1999, 567 p.
2. German K.E., etc.// Journ. Nucl. Radiochem. Sci. (2006) V. 6, No.3, pp. 211-214.
3. Peretrukhin V.F., etc. // J. de la Soc. de Chim. D.I. Mendeleiev (2007) v.51, No 6, p.11-23.
4. German K., Reich T., Sergeant C., etc. Proceedings of OECD/NEA Workshop on pyrochemistry. 1416 March 2000. Palais-des-Papes, Avignon (France).
5. M. Simonoff, K. E. German, C. Sergeant etc. Journee Radiochimie 2000, Gif-sur-Yvette, 28-29
September, 2000, France.
6. F.Poineau, Ph.F.Weck, K.German, etc. // Dalton Trans. (2010) 39 (37), pp. 8616-8619.
7. Supel J., Abram U. Hagenbach, etc. // Inorg. Chem. (2007) 46(14), 5591-5595.
8. V.Yu Murzin., Ya.V.Zubavichus, M.V.Chukalina, et all. This issue. 2011, p.172.
9. F. Poineau, E. V. Johnstone, Ph. F. Weck, E. Kim, P. M. Forster, B. L. Scott, A. P. Sattelberger, K.
R. Czerwinski. // J. Am. Chem. Soc., 2010, 132 (45), pp. 15864–15865.
10. F. Poineau, A. P. Sattelberger, B. L. Scott, P. Forster, Ph. Weck, E. Johnstone and K. R. Czerwinski.
This issue. 2011, p.31 and 60.
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RHENIUM IN NICKEL-BASE SUPERALLOYS FOR SINGLE CRYSTALGAS TURBINE BLADES
E.N. Kablov, N.V. Petrushin, V.V. Sidorov
All-Russian Scientific Research Institute of Aviation Materials, Moscow, admin@viam.ru

Development of high effective materials and new technologies for their manufacture
and application is the major factor of development of competitive aviation gas turbine
engines. According to CIAM data in the period from 1970 to 2000 dynamics of efficiency
increase of aviation engines of different generations was characterized by increase in the
maximal gas temperature at the input of the turbine from 1300-1450 K (third generation) up
to 1800-1950 K (fifth generation). Such growth has been attained owing to creation of newmaterials, basically nickel-base superalloys with high operational characteristics, perfectionof cooling systems of turbine blades. In promising engines of the sixth generation the gas
temperature will increase up to 2000-2200 K due to application in the turbine of single
crystal blades from the rhenium and ruthenium alloyed nickel-base superalloys.
Studies carried out have shown that rhenium is one of the most effective alloying
elements in nickel-base superalloys. Rhenium alloying was found to increase the incipient
melting temperatures of alloys and the temperature of complete dissolution of a hardening
γ′-Ni3Al-based phase in a nickel-based γ solid solution. Rhenium decreases the selfdiffusion coefficient of nickel and hinders diffusion processes in nickel alloys at operating
temperatures.
The rhenium concentration reaches 3-4 wt.% in second generation single crystal
superalloys and 5-6% in third generation superalloys. The superalloys designed at the AllRussian Scientific Research Institute of Aviation Materials (VIAM) contain 6-12% Re.
These high-rhenium superalloys with a single-crystal structure were designed with acomputer.
It is shown that for stabilization of phase structure and decrease in probability of
precipitation of TCP phases it is possible to alloy with ruthenium high-rhenium nickel
superalloys. Joint alloying with rhenium and ruthenium has synergetic influence on
characteristics of single crystal nickel superalloys. As a result their high-temperature stressrupture and temperature efficiency considerably increases. Application in engines ofdeveloped rhenium- and ruthenium –bearing nickel superalloys having stress rupture of120-130MPa at temperature of 1100 ºС for 1000 hours, will provide increase by 50-60 ºС ofworking temperature of single crystal blades made of these alloys.
The domestic sources of rhenium are examined for provision with rhenium theproduction of Re bearing alloys. Scientific and industrial complex on development andseries production Re bearing superalloys is arranged in VIAM.

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Organizing Committee at the Openning lecture(acad. B.F. Myasoedov, acad. A.Yu. Tsyvadze, A. Belova (ROSNANO), S. Vorobiev(ISTC), second row: workgroup Ya. Obruchnikova, N. Kravchenko and E. Nazarov)

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ISTR RETROSPECTIVES AND PROSPECTS - IN VIEW POINTSOF NUCLEAR FUEL CYCLE
M.Ozawa.
Tokyo Institute of Technology, Research Laboratory for Nuclear Reactors,
2-12-1 N-21, Ookayama, Meguro-ku,Tokyo, 152-8550, Japan

History of Technetium Symposium
1. Tc 1993 – Topical Symposium on the Behavior and Utilization of Technetium (Sendai,
Japan, March 18-20, 1993)
2. Tc 1996 – Russian-Japanese Seminar on Technetium (Moscow, Russia, July 1-5, 1996)
3. Tc 1999 – 2nd Japan - Russian Joint Seminar on Technetium (Shizuoka, Japan Nov.29 Dec.2 1999)
4. Tc 2002 – 3rd Russian - Japanese Seminar on Technetium (Dubna, Russia, June 23 – July
1, 2002)
5. IST 2005 – International Symposium on Technetium – Science and Utilization (Oarai,
Ibaraki, Japan, May 24-27, 2005) (Fig. 1).
6. IST 2008 – 6th International Symposium on Technetium and Rhenium − Science andUtilization (Port Elizabeth, South Africa,
October 7-10, 2008) . The 6th delegateshonored Prof.Yoshihara for his pioneering role in the Tc chemistry. (Fig.2).
7. ISTR 2011 - 7th International Symposium on Technetium and Rhenium − Science andUtilization (Moscow, Russia - July 4-8, 2011)
8. ISTR2014 -8th (USA)Fig. 1. JAEA Chirdren’s Science Center, O-arai, wasattacked by TSUNAMI. Re-opened on 19th April, 2011

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Fig.2. International Advisory Board of the ISTR2008

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Fundamental Research in Physics andChemistry of Tc and Re.

A. BELOVA (ROSNANO), S. VOROBIEV (ISTC) AND
M. OZAWA (SESSION CHAIRAMAN)

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SPECTROSCOPIC AND PHOTOPHYSICAL PROPERTIES OFCHALCOGENIDE-CAPPED OCTAHEDRAL HEXARHENIUMCOMPLEXES WITH N-HETEROAROMATIC LIGANDS
Takashi Yoshimura, Chiaki Suo, Shoji Ishizaka, Akitaka Ito, Eri Sakuda, Atsushi Shinohara, andNoboru Kitamura
Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan,
tyoshi@chem.sci.osaka-u.ac.jp
Department of Chemical Sciences and Engineering, Graduate School of Chemical Sciences and Engineering,
Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan

It is known that the 24 valence octahedral hexanuclear molybdenum, tungsten, and rhenium
complexes with an M6Q8 core (M = Re, Q = S, Se, Te; M = Mo, W, Q = Cl, Br, I) show
photoluminescence.
In this study, the new hexarhenium
complexes with N-heteroaromatic ligands
were synthesized and their photoluminesent
properties were characterized.
Photoirradiation of an CH3CN solution of(Bu4N)4[Re6S8Cl6] in the presence of 10
equiv.
ofpyridine(py)
gave(Bu4N)3[Re6S8Cl5py]. Emission spectroscopy
in deaerated CH3CN at 296 K was conducted
at 355 nm excitation.

Rhenium
The mono-py complex exhibited broadand structureless emission with the maximum
wavelength (em) = 754 nm, the emission
quantum yield (em) = 0.040, and the emission
lifetime (em) = 4.6 s.

Chalcogenide, Halide
Termianl ligand
Fig.1. Octahedral Hexarhenium Complex.

The spectroscopic and photophysical data
are similar to those of (Bu4N)4[Re6S8X6] andthe previously reported py coordinate complexes (Bu4N)4n[Re6S8Cl6n(py)n] (n = 2, 3). The
present results indicate that the emissive state is the cluster core-centered excited triplet state.
A mono-ppy (ppy = 4-phenylpyridine) complex (Bu4N)3[Re6S8Cl5ppy] were synthesized by
the similar method to prepare the mono-py complex. The complex showed emission at 739 nm(em = 0.0089) in deaerated CH3CN and at 690 nm in the crystalline phase at 296 K with an
excitation wavelength at 355 nm. The emission lifetime (em) of 0.33 s in CH3CN indicates thatthe excited-state is composed a triplet character. The transient absorption spectrum in deaerated
CH3CN showed a band at 410 nm. This spectral feature is well observed in the absorption ofaromatic anion; the absorption spectrum of the ppy also shows the bands in these regions. These
facts indicate that the excited-state of mono-ppy complex involves the * character of ppy.

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1.2.
RHENIUM OCTAHEDRAL CHALCOHYDROXO CLUSTER COMPLEXES
Y.V. Mironov, S.S. Yarovoi, K.A. Brylev, V.E. Fedorov
Nikolaev Institute of Inorganic Chemistry of SB RAS, Novosibirsk,
Russian Federation, e-mail:yuri@niic.nsc.ru

In recent years considerable research has been put into the design of solids withextended polymeric structures based on rhenium cluster cyano complexes. Here we
present a new group of compounds that are also able to form polymeric compounds–
anionic octahedral chalcohydroxo complexes [Re6Q8(OH)6]4– (Q = S or Se) andbioctahedral thiohydroxo one [Re12CS17(OH)6]6–. The Re6-based complexes weresynthesized by the reaction of Re6Q8Br2 with molten KOH in the air, while the Re12 one
was obtained by the reaction of ReS2 with KCN at 750oC with further interaction of theobtained product with molten KOH.
[Re6Q8(OH)6]4– (Q = S, Se) anions consist of six rhenium
atoms forming an octahedron, eight chalcogen atoms (S or Se)
form a cube around the octahedron. OH terminal group
coordinates each Re atom.
Cluster unit [Re12CS17(OH)6]
consists of two Re6 octahedra
bonded by three 2-S bridges andone common 6-C atom. EachRe6 cluster is caped by 7 3-S
and additionally by C ligand; one might say that here
the typical octahedral cluster core {Re6Q8} (where Q =S7C) is formed. Such bonding and coordination allow torecognize in this structure the trigonal 6-C-centeredprisms {Re6C} in which the triangle faces belong to two
adjacent Re6 octahedra. Six outward Re atoms (treefrom each Re6 cluster unit) are coordinated by OH ligands.
In this work we present the data on preparation of OH-bridged complexes based oncluster anions [Re6Q8(OH)6]4– (Q = S, Se) and cations of the II main group elements.
The first example of chain structure with 3d transition metals, namely,[Ni(en)2(H2O)2][{Ni(en)2}Re6S8(OH)6] has been also obtained. Also we present the dataof study of the substitution reactions of OH ligands by organic and inorganic ligands.
The authors are grateful to Russian Foundation for Basic Research (grants N 11-0300157-а and 10-03-01040-а ) for financial support.

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1.3.
TECHNETIUM HALIDES: FROM MOLECULAR
TO EXTENDED STRUCTURES
Frederic Poineau1*, Alfred P. Sattelberger2, Brian L. Scott3, Paul Forster1,
Philippe Weck1, Erik Johnstone1 and Kenneth R. Czerwinski1
1

Department of Chemistry, University of Nevada Las Vegas, Las Vegas, NV, 89154, USA
Energy Sciences and Engineering Directorate, Argonne National Laboratory, Argonne, IL 60439, USA
3
Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA*poineauf@unlv.nevada.edu
2Binary transition metal halides exhibit a rich chemistry, and the study of theirstructure, bonding and physical properties permits a better understanding of the physicochemical trends across the periodic table.
Because technetium and rhenium are members of the same group in the periodic
table, the occurrence of analogous coordination compounds is expected. In the case of thehalides, thirteen binary phases have been reported for rhenium, but only three were, until
recently, known for technetium, i.e., TcF6, TcF5, and TcCl4.
The direct stoichiometric reactions between technetium metal and elemental bromine
or chlorine as well as the reaction between the quadruple bonded dimer Tc2(OAc)4Cl2 with
HXg (X = Cl, Br) have, to the best of our knowledge, never been reported.
In this talk, we provide details of these reactions, which have led to the synthesis,
spectroscopic and structural characterization of several new technetium binary halides,
including TcCl2, TcCl3, TcBr3 and TcBr4.
The structures and formation mechanism of these new halides will be presented,
discussed, and compared with those of rhenium and molybdenum homologues.
Emphasis will be on TcCl2 which exhibits a new solid-state structure type withmetal-metal multiple bonds. Synthetic reaction using technetium binary halides as precursor
will also be presented.

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1.4.
SYNTHESIS OF RHENIUM ALKOXIDES VIAANODIC DISSOLUTION
E.N. Pryamilova, O.V. Chernyshova, D.V. Drobot
Lomonosov’s Moscow State Academy of Fine Chemical Technology, Moscow, Vernadskogo avenue 86(e-mail: san13greal@yandex.ru, oxcher@mail.ru)

At the first time the research of the process of rhenium anodic dissolution in absolute alcohols
was carried out using the electrochemical technological complex “ECC – 1012”, the measurementof potential being based on noncompensatory feed-back method. The device allows both toinvestigate, and to realize technological processes in optimum modes at controllable parameters.
The main application of rhenium is preparation of structural alloys with other refractory
metals. These alloys possess valuable mechanical properties and stability against evaluatedtemperature and corrosive medium. Another application of rhenium is preparation of highly-active
and selective catalysts for organic and hetero-organic synthesis. The using of rhenium alkoxides andoxoalkoxides permits to escape difficulties occurring in the traditional methods of preparation of
Re-based alloys and oxide materials.
The electrochemical synthesis of rhenium alkoxides is of heightened interest, because it isflexible, less complicated in hardware design and it allows carrying out the process under maximum
control via setting definite parameters. The electrochemical synthesis of alkoxides corresponds tothe anodic dissolution of rhenium in the required non-aqueous alcohol in the presence of abackground electrolyte. According to this method the processes of rhenium anodic dissolution inabsolute alcohols ROH (R = Me, Et, i-Pr etc) with the addition of LiCl were researched andrhenium complexes Re4O4(OEt)12, Re4O2(OBun)8∙8BunOH, Re4O6(OiPr)10, Re4O6(OMe)12 etc wereobtained for the first time with further investigation of their properties [1].
In order to observe the influence of electrochemical factors on the anodic dissolution thenumber of processes were carried out under controlled potential. The constancy of electrochemicalparameters was supported by means of electrochemical complex “ECC – 1012”. Besides,
heteroligand complexes of common formulas Re4Ox(OEt)y(OPri)z, Re4Ox(OEt)y(OCH2CF3)z wereprepared for the first time. The possible mechanism of rhenium anodic dissolution and its further
behavior in the solution was suggested.
The research was carryed out under the support of the RFBR grant № 09-03-00328.
1. Drobot D.V., Shcheglov P.А. Reviews, Rhenium alkoxides // Russian Chemical Bulletin,
International Edition. October 2005. v. 54, № 10, p. 2177-2188.

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1.5.
RHENIUM COORDINATION CHEMISTRY: OLD LIGANDS DIE HARD
Thomas Gerber1, Kim Potgieter1, Peter Mayer
1

Chemistry Department, Nelson Mandela Metropolitan University, 6000 Port Elizabeth, South Africa
2
Chemistry Department, Ludwig-Maximilians University, D-18377 Munich, Germany

The development of the coordination chemistry of Re and Tc has mainly focused on the +V and +Ioxidation states, since they are easily accessible from the permetallates. There is currently a general
notion amongst researchers in this field that there is very little scope in the further exploration of thecoordination chemistry of these oxidation states, since all routes and possibilities have been
exhausted, and the new focus has shifted to the states +II, +III, +IV and +VI.
We have used relatively simple and common organic molecules, like 2-aminobenzenethiol, 1,2diaminobenzene, 2-aminophenol, imidazoles, thiazoles, and their derivatives, as possible ligands forrhenium(I) and (V). In many instances, surprisingly unexpected complexes were found, dependingon the starting complexes used and the reaction conditions. For example, with the simple ligand 2aminobenzenethiol, the unusual disulfide-bridged rhenium(I) complex 1 and rhenium(VI) complex
2 have been obtained.
Many other examples of unusual complexes with simple ligands will be presented and discussed interms of their spectroscopic and crystallographic data.

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1.6.
REDOX BEHAVIOUR OF THE Tc(VII)/Tc(IV) COUPLE IN DILUTED NaCl
SOLUTION IN VARIOUS REDUCING SYSTEMSTaishi Kobayashi, Xavier Gaona, David Fellhauer1, Marcus Altmaier
Karlsruhe Institute of Technology, Institute für Nukleare Entsorgung, P. O. Box 3640, 76021 Karlsruhe,
Germany1.
European Commission, Joint Research Centre, Institute for Transuranium Elements, P. O. Box 2340, 76125 Karlsruhe,
Germany

Keywords: technetium, redox behaviour, TcO2·xH2O(coll,hyd), Eh-pH conditions, dilute NaCl
Abstract:
The redox behaviour of the Tc(VII)/Tc(IV) couple over a wide range of pH conditions in 0.1 M
NaCl/NaOH solution was investigated in various homogenous and heterogenous reducing systems.
Stock solution of Tc(VII) was added to each reducing system, and after given periods, the Tc
concentration was measured and compared to the initial Tc(VII) concentration (1·10−5 mol/dm3).
The results can be systematized according to Eh-pH conditions in solution and a general borderline
for the reduction of Tc(VII) to Tc(IV) independent of the reducing systems is obtained. The
experimental borderline is slightly lower than the calculated equilibrium line between TcO4− andTcO2(s)·xH2O(s). This may suggest that more soluble solid phase such as small Tc(IV)oxyhydroxide particles are formed under the given conditions. Reaction kinetics are also discussed
and correlated to the measured redox potentials and the reduction borderline.
Introduction
The migration behaviour of 99Technetium in geological systems relevant to nuclear waste disposal
is primarily depending on its oxidation state. In +VII oxidation state, Tc exists as the anionic TcO 4−
ion which is highly soluble and mobile in the environment, while Tc in +IV oxidation state under
reducing condition is easily hydrolyzed to form sparingly soluble Tc(IV) oxyhydroxide solid
phases. The redox potential of the Tc(VII)/Tc(IV) couple has been investigated in many studies bymeasuring the electrode potential [1-4]. Meyer et al. reduced Tc(VII) to Tc(IV) solids(TcO2·1.6H2O) electrochemically in acidic solution, and determined the standard potential of
TcO4−/TcO2·1.6H2O(s) couple to be Eº = 0.747±0.004 V according to TcO4– + 4H+ +3e– =TcO2·1.6H2O(s) + 0.4H2O [4]. A comprehensive review of the thermodynamic data has been
performed [5], and Tc predominant diagram (Eh-pH diagram) was proposed based on the selected
thermodynamic data. On the other hand, in laboratory and natural systems, where many kinds ofsolution species and solids containing iron ions and minerals were used as reductants, various Tc
redox behaviours have been observed [6-13]. For the reliable quantitative prediction of Tc
migration behaviour, it is important to systematize Tc redox behaviour with the Eh-pH diagramfrom the aspect of thermodynamic data. In the current study, the redox behaviour of Tc(VII)/Tc(IV)couple was investigated in various kinds of homogeneous (anthraquinone, hydroquinone, 2hydroxy-1,4-naphthoquinone, and Na2S2O4 systems) and heterogeneous (Fe(II)/Fe(III), Fe powder,
Sn(II) systems) reducing systems, and compared to the thermodynamically calculated equilibriumline for TcO4−/TcO2·xH2O(s) within the Eh-pH diagram. The systematization of Tc redox processes
in various reducing systems offers a straightforward approach for predicting the predominantoxidation state of Tc under repository relevant conditions and is also important for the reliableprediction of Tc migration behavior in geological system.

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Experimental
Aliquots of NaTcO4 stock solution was added to 0.1 mol/dm3 (M) NaCl/NaOH pre-equilibrated
with the following reducing agents (p.a. grade chemicals); 3 mM anthraquinone disulfonate(AQDS) (ratio of oxidized form (ox.) to reduced form (red.) = 1:3), 3 mM hydroquinone solutions,
Fe(II)/Fe(III) mixed solutions and precipitates (Fe(II):Fe(III) = 1 mM:0.1 mM), 1 mM Na2S2O4
solutions, Fe powder suspensions (1 mg/15 ml), 2-hydroxy-1,4-naphthoquinone (Lawsone)
solutions (ox.:red. = 1:3), and 1 mM Sn(II) solutions and precipitates. The initial Tc(VII)concentration was set to 10−5 M. The hydrogen ion concentration (pHc) of the sample solutions
were adjusted by adding HCl (Merck) and carbonate-free NaOH (Baker), using a combination glass
electrode (type ROSS, Orion) calibrated against standard buffers (pHc 2 – 12, Merck). The redox
potential was measured with a combined Pt and Ag/AgCl reference electrode (Metrohm). The
measured redox potentials were converted to redox potential (Eh) versus the standard hydrogenelectrode (S.H.E.) by the correction for the potential of the Ag/AgCl reference electrode (+208 mV
for 3 M KCl junction electrolyte). The apparent electron activity (pe = −log ae−) was calculated
from Eh = −(RT/F) ln ae− according to the relation: pe = 16.9 Eh (V) at 25 °C.
After given periods up to several months, pHc and Eh values were measured and the supernatants ofthe solutions filtrated through 10 kD (2-3 nm) ultrafiltration membranes (Pall Life Sciences). The
Tc concentration was determined by Liquid Scintillation Counting (TriCarb 2500 Tr/AB
instrument, Canberra-Packard) with a detection limit of ~10−8 M. The Tc oxidation state of thesoluble species was investigated by solvent extraction technique, where TcO4− was extracted into
chloroform using 1 mM tetraphosphonylchloride (TPPC). All samples were prepared and stored in
an Ar glove box under inert gas atmosphere.
Result and Discussion
E0.8
-4
h (V)
"redox neutral"
12
1. Redox behaviour of(pe + pH = 13.8)
Initial Tc(VII) concentration
0.6
1 bar O (g)Tc(VII)/Tc(IV) in the-58
0.4
individual
reducing
systems
4
0.2-6
The Tc concentrations after0
0.0
ultrafiltration
were
-7
-0.2
investigated over a wide
3 mM HQ-4 3 mM HQ
3 days3days
pHc range as a function of
7 days-0.4
7 days-8-821 daystime. In hydroquinone
21 days
49 days
-0.6
49
days
1
bar
H
(g)
solutions, Tc concentration -12
detection limit
246 days
246 days-0.8-9
was constant at the initial
02
4
6
8 10 12 14
02
46
8 10 12 14
TcO4− concentration level++- log [H ]log
[H]from pHc 2.2 to 12.3 for up
to 8 months (Fig. 1). The Ehvalues are slightly higher Fig. 1. Eh and Tc concentrations (10 kD filtration) in 3 mM thantheequilibriumline hydroquinone (HQ) solutions as a function of pHc. The broken line−−
betweenTcO4
and represents the calculated equilibrium line between TcO4 and
TcO2·xH2O(s) calculated TcO2(s)·xH2O(s) [5].
from the literature [5]. In
theoxidation state analysis for the samples at pHc 3.9, 8.5, and 12.3, more than 99% of total Tc in thesolutions was extracted to the organic phase, indicating that dominant species is TcO4− and no
reduction of Tc(VII) had occurred.
In AQDS redox buffer solutions at pHc 5.0 and 8.1, the initial Tc concentration (10−5 M)decreased rapidly to about 10−7 M, suggesting that TcO4− was reduced and sparingly soluble
TcO2·xH2O(s)(s) had precipitated. In contrast, at pHc 10.5, a considerably slower reduction wasobserved. Under alkaline condition at pHc > 11, Eh values are higher than the calculated TcO4− /pelog [Tc]

2

2

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011log [Tc]log [Tc]

TcO2·xH2O(s)(s) equilibrium line and the Tc concentration is constant at initial TcO4− concentrationlevel, indicating that no reduction of Tc(VII) occurred within the investigated time.
In Lawsone redox buffer solutions, the Tc concentration decreased from the initial Tc(VII)concentration level over the entire investigated pHc range of 2 - 12. In the alkaline pH region,
extremely slow reduction was observed and not reached the equilibrium state up to 85 days.
In the systems with Sn(II), the white Sn(II)-4hydroxide precipitate was observed in the range ofpHc
Sn(II)
5-11 before adding Tc(VII) stock solution. At-5higher pH the precipitates disappear and anionic
pHc = 12.6, pe = –11.7-6
Sn(II) hydrolysis species (Sn(OH)3−) considereddominant [14]. The Tc concentration decreases-7
pHc = 11.1, pe = –10.2
rapidly over the pHc range 2 - 11 and stableconditions are achieved within several days (Fig. 2).
At
-8
pHc
=
8.5,
pe
=
–7.1
detection
limit
pHc > 11, the concentration of reduced Tc(IV)-9species increases with increasing pHc. The results
of
0
10
20
30
40
50
the oxidation state analysis by solvent extraction
time (days)
under these pH conditions indicates negligible
contribution of remaining Tc(VII), suggesting the Fig. 2. Tc concentrations (10 kD filtration)formation of anionic Tc(IV) hydrolysis species such in 1 mM Sn(II) solutions and precipitates as
as anionic TcO(OH)3− as proposed in the literature a function of time.
[15,16].
In Na2S2O4 solution in the pHc range 6.9 - 10.9, the Tc concentrations in the solutions decrease andstable state conditions (10−7 - 10−8 M) are achieved within a few weeks, indicating the reduction ofTc(VII) to a Tc(IV) solid. Similarly to the literature where Na2S2O4 was used to reduce Tc(VII) forthe preparation of Tc(IV) solid phase (TcO2·xH2O) [17], a black-colored Tc(IV) solid phase wasimmediately precipitated, however, an aging time of a few weeks is needed to reach equilibrium
state. At pHc > 11, the Tc concentrations after reduction increases with an increase of pHc,suggesting the formation of anionic Tc(IV) species similar to Sn(II) system. It should be noted thatat pH 6.9, the amount of Tc(VII) in the solution was more than 30 %, as under neutral pH
conditions Na2S2O4, which is supposed to maintain reducing conditions, is not stable overprolonged periods of a few months.
In the system of Fe(II)/Fe(III) mixed solutions and precipitates, at pHc = 2.1 and pe = 11.3, nochange in the Tc concentration was observed up to 49 days. On the other hand, at pHc 6.0 (pe =−0.2) and pHc 8.4 (pe = −0.2), Fe(II)/Fe(III) solid phase precipitates were observed before adding
Tc(VII) stock solution and the Tc concentrations decreased to almost detection limit (10−8 M)within three days after Tc(VII) was added. The reduction-4
Fe powderof Tc(VII) with Fe(II)/Fe(III) redox buffers and
pHc = 12.1, pe = –5.2
suspensions of the precipitates has been reported in-5several studies. Cui et al. reported that the TcO4–
pHc= 10.2, pe = –4.8
-6
concentration at pH < 7.5 was constant at initialconcentration level over a few days in the presence of-7
about 10−5 M aqueous Fe(II) [8]. Ben Said et al. showed,
reduction kinetics were also depending on the Fe(II)-8pHc = 9.3, pe = –5.3
concentration, Fe(II)/Fe(III) ratio, and initial Tc(VII)detection limit-9
concentration [9]. The difference between Cui et al. [8],
0
20
40
60
80
100
Ben Said et al. [9], and our results probably arise from thetime (days)
different experimental conditions such as Fe(II)concentration. Unfortunately, the redox potentials in Fig. 3. Tc concentrations (10 kD filtration)these studies were not reported. Zachara et al. also in 1 mg / 15 ml Fe powder suspensions as ainvestigated the reduction of Tc(VII) in Fe(II) systems infunction of time.
near neutral pH range and the redox behavior was
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

supported by measured redox potentials [11]. The observed rapid reduction at pH > 6.8 generally
agrees with the results in this study, although the reported Eh values were higher than those in thisstudy.
In the samples containing corroding Fe powder in the pHc range 6 - 10, the Tc concentration
rapidly decreased to the detection limit (10−8 M) within three days. In contrast, no reduction wasobserved in all samples at pHc > 10 as shown in Fig. 3.
2. General trends of Tc(VII)/Tc(IV) redox behaviour and kinetic effects
The results discussed above are summarized in the Eh-pH
E0.8
diagram shown in Fig. 4. Samples in which no reductionh (V)AQDS / AH QDS
12Hydroquinone
was observed are plotted as filled symbols. Samples in
Fe(II) / Fe(III)0.6
10which initial Tc(VII) was completely or partly reduced are
Fe powder8
plotted as open symbols. The bold dot line and broken line
0.4
No reduction
6in the figure represent an experimental borderline for40.2
Tc(VII) reduction obtained in this study and the calculated"redox neutral"2−(pe + pH) = 13.8
equilibrium line between TcO4 and TcO2·xH2O(s) [5],00.0respectively. The reduction of Tc(VII) to Tc(IV) occurred-2
in both homogeneous solutions and heterogeneous-0.2-4 Reductionsuspensions with redox potentials below the experimental-6
AQDS / AH QDS-0.4
borderline. In the systems with redox potentials above the
Na S O-8
1 bar H (g)
Fe(II) / Fe(III)borderline, Tc(VII) was not reduced. It should be noted -10-0.6
Fe powderthat in Fe powder systems, no reduction was observed at -12
Lawsone
Sn(II)Cl
pHc = 10.2 and pe = −4.8 up to 49 days, on the other hand,
-0.8
0
2
4
6
8+
10
12
14
Tc(VII) was slowly reduced at pHc = 10.5 and pe = −4.0 in- log [H ]
pe

2

2

2 2

4

2

2

the AQDS / AH2QDS solution. In Fe powder suspension, Fig. 4. Experimental plots on thethe deviation of measured Eh values are relatively large, reduction of Tc(VII) ([TcO4−]init = 10−5compared to stable Eh values in the AQDS / AH2QDS M). Samples reduced as open symbols,
solution.
samples not reduced as filled symbols.
In the investigated systems, the reduction of Tc(VII) to
Tc(IV) can be described with the equilibrium constant (K), and the equilibrium line (50 % Tc(VII),
50 % Tc(IV)) is calculated from the equation (shown as broken line in Fig. 1 and 4):
TcO4− + 3e− + 4H+  TcO2·xH2O(s) + (2−x)H2O(1)log Kº = log [TcO4−] −3 pe +4 log [H+](2)with log Kº = 37.8 ± 0.6 (I = 0) from the data selected by the Rard et al. [5]. For 0.1 M NaCl/NaOH
solution, the K value was corrected using the SIT method and ion interaction coefficients of ε (H+,Cl−) = 0.12 kg·mol−1 and ε (ClO4−, Na+) = 0.01 kg·mol−1 [18], which is taken as analog for ε(TcO4−, Na+). Under the condition of initial Tc concentration ([Tc]init) = 10−5 M, i.e., log [TcO4−] =log ([[Tc]init / 2]) = −5.30, the calculated borderline was pe = −1.3·(− log [H+]) + 11.0. The resultsin Fig. 4 indicates that the experimental borderline for the reduction of Tc(VII) (bold dot line) is
about 2 pe-units (about 100 mV) lower than the calculated line (broken line). This may suggeststhat the reduction with slow kinetics by reducing chemicals lead to different solid phases, or at leastdifferent particle size distribution compared to more crystalline solid phases assumed for thethermodynamic calculation. The value of log Kº for the Tc(IV) solid phase selected by Rard et al.
[5] was calculated from the standard redox potential (Eº) of Eq. (1), which was determined from theinvestigation of redox potential measurement data of the TcO4−/TcO2·xH2O(s) couple [1], [4]. In theliterature, the solid phases were prepared by electrochemical reduction of macroscopic amounts of
TcO4−. Under the experimental condition of lower initial Tc concentration in this study, Tc(VII)34

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

reduction rate (half life time) [day]may be precipitated not as TcO2·xH2O(s) but rather small colloidal particles, TcO2·xH2O(coll, hyd).
This explanation would be similar to the Np(V) reduction processes and the role of colloidal Np(IV)phases described recently by Neck et al. [19]. In their study on the reduction of Np(V) to Np(IV),the experimental borderline was also observed to be lower than the calculated equilibrium line fromthe thermodynamic constant of NpO2(am, hyd) and NpO2(coll, hyd) considered as small solid phaseparticles was proposed. In Fig. 4, the experimental borderline was determined to be pe = −1.3·pH +9.3, and log K for TcO2·xH2O(coll,hyd) was obtained
60
AQDS / AH QDS
to be 33.1 at I = 0.1.
Na S OThe kinetics for the reduction of Tc(VII) generally50
LawsoneFe powder
showed a significant dependence on Eh in
Sn(II)
40
homogeneous solutions systems (Fig. 5). The reduction
rate decreased when Eh increased from strongly
30
negative values, such as in Sn(II) system, to near the20
reduction borderline and in the systems such as
Lawsone, the rate of reduction was extremely slow. On
10
the other hand, a rapid decrease of the initial Tc
0concentration was observed in suspensions where the
0
1
2
3
4
5
6
7
Eh values were lower than the borderline in Fig.4. In pe
Fe powder suspensions at pHc < 10, the Tc
Fig. 5. Reduction rate half life time as aconcentration decreased to detection limit level (10−8function of the difference of pe valuesM) within 3 days, although the Eh values were closed
between the measured value in eachto those in the Lawsone system, where slow kinetics
reducing system and experimental
were observed.
2

2 2

4

Conclusions.
The redox behaviour of Tc(VII)/Tc(IV) couple was investigated in various homogeneous andheterogeneous reducing systems and systematized according to pH-Eh conditions. A borderline forthe reduction of Tc(VII) independent of reducing systems was shown and Tc(VII) was reduced
when the redox potential values were below this borderline in both homogeneous solutions andheterogeneous suspensions. In the systems with redox potentials above the borderline, initial
Tc(VII) concentration did not changed, indicating no reduction of Tc(VII). The experimental
borderline was about 2 pe unit lower than the equilibrium line calculated from the standard potentialof TcO4−/TcO2(s)·xH2O(s), which was electrochemically prepared from macroscopic amounts of
TcO4−. The difference may suggest that analog solid phases with significantly smaller particle size
control the redox processes investigated in this study. For the confirmation of the proposed
TcO2·xH2O(coll, hyd), further investigation including solid phase analysis is needed. The kineticsof the Tc(VII) reduction was generally correlated to the Eh-pH conditions, however in the systemsof Fe powder suspension and Fe(II)/Fe(III) precipitates more rapid reduction was observed. Thispossibly implies the intrinsic properties of mineral surfaces and surface mediated redox processes.
Acknowledgement: The research leading to these results has received funding from the European
Union's European Atomic Energy Community's (Euratom) Seventh Framework Programme
FP7/2007-2011 under grant agreement n° 212287 (RECOSYproject). This work was partially
supported by the German BMWi under the project of VESPA.
References.
1. J. Cobble, W. Smith, G. Boyd, J. Am. Chem. Soc. 75, 5777-5787 (1953).
2. G. Cartledge, W. Smith, J. Phys. Chem. 59, 1111-1112 (1955).
3. B. Gorski, H. Koch, J. Inorg. Nucl. Chem. 31, 3565-3571 (1969).
4. R. Meyer, W. Arnold, Radiochim. Acta 55, 19-22 (1991).
35

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 20115.

Rard. J., Rand, M., Anderegg, G., Wanner, H. Chemical Thermodynamics of Technetium,
Elsevier. Amsterdam 1999.
6. E. Bondietti, C. Francis, Science. 203, 1337-1340 (1979).
7. K. Lieser, Ch. Bauscher, Radiochim. Acta, 42, 205-213 (1987).
8. D. Cui, T. Eriksen, Environ. Sci. Technol. 30, 2259-2262 (1996).
9. K. Ben Said, M. Fattahi, C. Musikas, A. Delorme-Hiver, J. Abbe, Radiochim. Acta. 83, 195203 (1998).
10. E. Maset, S. Sidhu, A. Fisher, A. Heydon, P. Worsfold, A. Cartwright, M. Keith-Roach,
Environ. Sci. Technol., 40, 5472-5477 (2006).
11. J. Zachara, S. Heald, B. Jeon, R. Kukkadapu, C. Liu, J. McKinley, A. Dohnalkova, D. Moore,
Geochim. Cosmochim. Acta. 71, 2137-2157 (2007).
12. I. Llorens, P. Deniard, E. Gautron, A. Olicard, M. Fattahi, S. Jobic, B. Grambow, Radiochim.
Acta, 96, 569-574 (2008).
13. J. Begg, I. Burke, J. Chamock, K. Morris, Radiochim. Acta, 96, 631-636 (2008).
14. C. I. House, G. H. Kersall, Electrochemica Acta. 29, 1459-1464 (1984).
15. T. Eriksen, P. Ndalamba, J. Bruno, M. Caceci, Radiochim. Acta, 58/59, 67-70 (1992).
16. P. Warwick, S. Aldridge, N. Evans, S. Vines, Radiochim. Acta, 95, 709-716 (2007).
17. N. Hess, Y. Xia, D. Rai, S. Conradson, J. Solution Chem. 33, 199-226 (2004).
18. Guillaumont, R., Fanghänel, Th., Fuger, J., Grenthe, I., Neck, V., Palmer, D., Rand, M., Updateon the Chemical Thermodynamics of Uranium, Neptunium, Plutonium, Americium andTechnetium, Elsevier, Amsterdam 2003.
19. Neck, M. Altmaier, D. Fellhauer, J. Runke, Th. Fanghänel, Collaborative Project “Redox
Phenomena Controlling Systems” 1st Annual Workshop Proceedings, 65-73 (2009).

Welcome to Moscow, Lenininsky prospect, 31
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1.7.
TECHNETIUM(I) HEXACARBONYL CATION AND ITS REACTIVITY
A.E. Miroslavov1, G.V. Sidorenko1, A.A. Lumpov1, D.N. Suglobov1,
M.S. Grigor’ev2, and V.V. Gurzhii3
1

Khlopin Radium Institute, Research and Production Association, Federal State Unitary Enterprise,
2-i Murinskii pr. 28, St. Petersburg, 194021 Russia
2
Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
3
St. Petersburg State University, St. Petersburg, Russia

Technetium(I) hexacarbonyl cation [Tc(CO)6]+ was prepared by autoclave carbonylation of[Tc(CO)3(H2O)3]+ with CO at 100°С in the presence of strong acids with weakly coordinatinganions (HClO4, CF3SO3H, HPF6). With strongly coordinating acid anions (e.g., Cl–), thepentacarbonyl complex with the acid anion is formed. The [Tc(CO)6]+ cation, isolated in the formof perchlorate, was characterized by single crystal X-ray diffraction (SC XRD) and by IR (νCO,
MeCN: 2095 cm–1) and 99Tc NMR (δTc, MeOH: –1924 ppm) spectroscopy. The crystal structure of[Tc(CO)6]ClO4 consists of one crystallographically independent Tc(CO)6+ cation and disordered
ClO4- anion (Fig. 1).

Fig. 1. [Tc(CO)6] + cation (left) and disorderedperchlorate anion (right) in the structure of[Tc(CO)6]ClO4.

Since [Tc(CO)6]+ is an analog of MIBI, it was of interest to study its cardiotropic properties. For
this purpose we examined the resistance of this complex to substitution of carbonyl groups insolution. As an incoming ligand, we tested acetonitrile (mild σ donor). As seen from the IR data,[Tc(CO)6]+ slowly reacts with MeCN to form [Tc(CO)3(MeCN)3]+. As in the case of pentacarbonyl
halides [1], the rate-determining step of decarbonylation is detachment of carbonyl group. The rate
constant of this reaction (2.83 × 10–7 s–1, 304.4 K) is more than 1.5 orders of magnitude lower thanthat of decarbonylation of the most stable complex among pentacarbonyl halides, [TcI(CO)5] (76 ×
10–7 s–1, 303.1 K, in CCl4 [1]). Thus, the [Tc(CO)6]+ cation is fairly resistant to thermal
decarbonylation, despite relatively large lengths of the Tc–CO bonds. However, [Tc(CO)6]+ isinstantaneously hydrolyzed in an aqueous solution in the presence of an alkali to form an
unidentified yellow precipitate, which is probably a mixture of different compounds. Vacuum
sublimation of this product yielded Tc2(CO)10 and Tc3H3(CO)12, identified by SC XRD. We suggestthat in this case decarbonylation involves nucleophilic attack of OH– anion at the carbonyl carbon
atom, followed by decarboxylation of the intermediate and secondary transformations of thedecarboxylation product.
We also prepared [99mTc(CO)6]+ by autoclave carbonylation of [99mTc(CO)3(H2O)3]+ in aqueous
solutions of HPF6 or CF3SO3H with a yield of 40 and 15%, respectively. The key point of thesynthesis is complete removal of halide ions from the reaction mixture. [ 99mTc(CO)6]+ is stable inacidic aqueous solutions and in the presence of histidine for a day.
1. A.E. Miroslavov, G.V. Sidorenko, A.A. Lumpov, V.A. Mikhalev, D.N. Suglobov,
Radiokhimiya 51: 6–10 (2009).

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

1.8.

STRUCTURAL CHEMISTRY OF TECHNETIUM CARBONYLCOMPOUNDS
G.V. Sidorenko1, A.E. Miroslavov1, D.N. Suglobov1, M.S. Grigor’ev2, and V.V. Gurzhii3
1

Khlopin Radium Institute, Research and Production Association, Federal State Unitary Enterprise,
2-i Murinskii pr. 28, St. Petersburg, 194021 Russia
2
Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
3
St. Petersburg State University, St. Petersburg, Russia

Keywords: technetium, carbonyls, structure, single crystal X-ray diffraction
Abstract:
The results of structural studies of Tc carbonyl compounds are summarized. The
stoichiometry and geometry of the mono- and polynuclear complexes are discussed in relation to
the donor–acceptor properties of the ligands, taking into account the trans effect. Correlations
between the structure and reactivity of the complexes are considered.
In this report we summarize the results of structural studies of Tc carbonyl compounds. By
now, crystal structures have been determined for approximately 100 Tc carbonyl complexes, ofwhich 17 complexes have been studied by us. Most of the data refer to octahedral Tc(I) complexes,
with some Tc(III) and Tc(0) compounds also studied. Tc(III) typically forms seven-coordinate
complexes with CO ligands (see, e.g., [1]), but with sterically hindered ligands five-coordinate
complexes
areformed
[2].
Here
and
hereinafter,thedenticityof
π-coordinated ligands like cyclopentadienyl is counted by the number of π-electron pairs involvedin the coordination. The known Tc(0) complexes are technetium decacarbonyl Tc2(CO)10 [3, 4](Fig. 1) and some of its derivatives [5].
The composition of Tc(I) carbonyl complexes is dictated by formation of closed
18-electron valence shell around the central atom. Therefore, the known complexes have typicallyoctahedral structure. Representatives of practically all the theoretically possible mononuclear Tc(I)
carbonyl complexes have been prepared and structurally characterized (here and hereinafter: M,
monodentate; B, bidentate; T, tridentate ligands): [Tc(CO)6]+, [Tc(CO)5M], [Tc(CO)4B],[Tc(CO)3T], [Tc(CO)3BM], [Tc(CO)3M3], [Tc(CO)2M4], [Tc(CO)2BM2], [Tc(CO)2TM],[Tc(CO)TM2]. The charge of the complex species depends on whether the ligands are neutral or
charged, and in this notation the charge is omitted.
The trans effect makes preferential mutual cis arrangement of carbonyl ligands. The Tc–CO
bonds in trans position weaken each other, and therefore technetium carbonyls containing morethan three carbonyl ligands, in which such bonds are inevitably present, are relatively unstable.
Nevertheless, many representatives of this group, including hexacarbonyl cation [6] (Fig. 2), aresufficiently stable to be isolated and studied by single crystal X-ray diffraction. All the available
structural data for technetium(I) pentacarbonyls [Tc(CO)5M] were obtained in our studies [7–9],
with both neutral (ButNC, PPh3) and anionic (Cl, Br, I) ligands as M. Typical examples are shownin Figs. 3 and 4. As for mononuclear tetracarbonyl complexes [Tc(CO)4B], the only available
example of structurally studied complexes is the xanthate (B = MeOCS 2–) examined in our recent
study [10] (Fig. 5). The most stable (and the most numerous) are fac-tricarbonyl complexes with σor π-donor ligands in trans position to each CO group {[Tc(CO)3T], [Tc(CO)3BM], [Tc(CO)3M3]}.
Typical examples are given in [10–14] (Fig. 6). The fac-tricarbonyl moiety is so stable and its stericrequirements are so strong that, even with the porphyrin ligand strongly dictating the square planar
geometry, a binuclear complex with tridentate coordination of the ligand to each Tc atom is formed[15]. Only ligands with pronounced π-acceptor properties are capable to form mer structures [16] or
to further replace CO groups. All the di- and monocarbonyl complexes studied contain other π38

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

acceptor ligands apart from CO (most frequently phosphines, see, e.g., [17, 18]).

Fig. 2. Structure of the [Tc(CO)6] +cation [6].

Fig. 3. Structure of the[Tc(CO)5(ButNC)] + cation [9].

Fig. 4. Molecular structure
Fig. 5. Molecular structure ofof [TcX(CO)5] (X = Cl, Br) [Tc(MeOCS2)(CO)4] (the OMe group[8].
is disordered over two sites) [10].

Fig. 6. Molecular structure of[Tc(acac)(Et2NH)(CO)3] [13].

Fig. 1. Molecular structureof Tc2(CO)10 [4].

The deficiency of ligands leads to formation of binuclear complexes. Numerous polynu-clear
Tc carbonyl complexes with bridging coordination of ligand donor atoms are known, in particular, aseries of dimers [Tc(CO)4M]2 and [Tc(CO)3B]2. Typical examples of the former complexes are
tetracarbonyl halide dimers [19] (Fig. 7). However, with M = H, a triangular trimer is formed, with
the Tc–Tc distance suggesting certain direct bonding [4, 20] (Fig. 8).
With bidentate ligands, the dimers are formed by bridging coordination of one of the donor
atoms of the ligand. In this case, the ligand arrangement can be either cis or trans relative to thebridging core. Both examples are known; in particular, a Schiff base complex forms acentrosymmetric trans dimer [21], whereas a dithiocarbamate complex has a noncentrosymmetriccis structure [10] (Fig. 9). The cis dimers are formed, according to IR spectra, by tricarbonyl-βdiketonates in solution and in the gas phase [22, 23]. Tricarbonyltechnetium acetylacetonate dimerin the crystal has a unique structure. The dimer is formed by bridging bonding with the γ-C atom oftheacetylacetonate
ligand
and
has
the
cage
structure[13](Fig. 10). Along with neutral dimers, anionic dimers with triple bridges of the composition[Tc(CO)3]2X3– are known (see, e.g., [24]). Binuclear complexes are also formed with somepolydentate ligands that can span two tricarbonyltechnetium fragments. One of examples, the39

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porphyrin complex, has already been mentioned.

I(1)Fig. 7. Molecular structure of [TcI(CO)4]2 [19].

Fig. 8. Molecular structure of [TcH(CO)4] 3 [4].

Fig. 9. Molecular structure of[Tc(Et2NCS2)(CO)3] 2 [10].

Fig. 10. Molecular structure of[Tc(acac)(CO)3(Et3NH)] [13].

In tricarbonyl complexes with single monodentate ligand, μ2-bridging is insufficient to attaincoordination saturation, each monodentate ligand links three Tc atoms, and the structure as a wholeis tetrameric and cubane-like. All the examined compoundsof this type [25–28] (Fig. 11) have similar molecular
structure but are not isostructural. They crystallize in
different crystal systems and have different crystal packing.
A related complex with CH3O– bridging ligands and Na+ inplace of one of tricarbonyltechnetium groups is also known[29].
Many transition metal carbonyls contain bridg-ing CO
ligands. Such coordination mode is not typical of Tc, but a
few examples are known (see, e.g., [30]). In all these cases,
CO bridging is observed in combination with direct Tc–Tc
bonding.
Fig. 11. Crystal structure of
After having discussed the compositions and[TcCl(CO)3]4 (body-centered cubic
topologies of Tc carbonyl complexes, let us discuss theirstructure, only the molecule in the cellgeometries and correlations with the reactivity.
center is shown) [26].
The length of Tc–CO bond in trans position to σ- andπ-donor ligands and in cis position to other CO groups [Tc–CO] is, on the average, about 1.9 Å. The Tc–CO bonds in trans position to each other [Tc–CO*] are40

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

weakened by the trans effect and are longer by 0.05–0.1 Å. The Tc–CO bond lengths in somehigher technetium carbonyls are compared in Table 1.
In [Tc(CO)5M] complexes, theTable 1. Bond lengths (Å) in higher technetium carbonyls difference in the lengths of these bonds(asterisk denotes CO groups trans to other ligands, and decreases in the series M = Cl, Br, I and
dagger, CO groups trans to each other)is practically leveled off in going to πacceptor ligands M (PPh3, ButNC). If we
ComplexTc–CO* Tc–CO† Difference include in this series Tc2(CO)10,+
considering the Tc(CO)5 fragment as[Tc(CO)6] [6]–2.024–2.032–
ligand M, it will occupy the place[TcCl(CO)5] [8]1.915
av. 2.016
0.099
between I and π-acceptor lig-ands. The[TcBr(CO)5] [8]1.937
av. 2.021
0.084
reactivity of Tc carbonyl complexes in[TcI(CO)5] [7]
1.938
2.015
0.077
dissociative carbonylation reactions does
[Tc(CO)5]2 [4]
1.946
av. 1.998
0.052+
not correlate with the Тс–СО bond length[Tc(CO)5(PPh3)] [9]2.005
av. 2.000
0.005t+
and decreases in the order M = Cl, Br, I,[Tc(CO)5(Bu NC)] [9]1.999
av. 2.014–0.014
CO [31], apparently due to the[TcI(CO)4]2 [19]av. 1.91
av. 2.00
0.09
stabilization of the five-coordinate[Tc(MeOCS2)(CO)4] [10] av. 1.940 av. 2.008
0.068
intermediate formed by СО elimination.
[TcH(CO)4]3 [4]av. 1.943 av. 2.002
0.059
The complex [Tc(CO)6]+ is particularly
inert in CO substitution, despite the fact that the Tc–CO bonds in it are even longer than the Tc–
COtrans bonds in [Tc(CO)5M] complexes.
The reactivity of [Tc(CO)5M] complexes can also
Table 2. Average angle X–Tc–cis-CO, deg, be influenced by the cis interaction ОС···М revealed byquantum-chemical calculations, which increases in goingand Wiberg indices ∑W(X···C,X···O)from М = Cl to M = I (Table 2). Such interaction is alsosuggested by angular distortions of the [Tc(CO)5M]
X Angle (XRD) Angle (QCC) ∑W
octahedra [M = halogen, Tc(CO)5]: The equatorial CO
Cl
89.23
86.7
0.24
groups lean toward ligand M to the extent increasing in
Br
88.27
86.5
going from Cl to I, despite an increase in the ligand size.
I
87.8
86.5
0.36
Quantum-chemical calculations also show this leaning,
though without pronounced trend along the halogen series, which suggests that the leaning is an
intrinsic property of a molecule rather than a result of packing effects. Leaning toward the sixth
ligand is also observed in Tc2(CO)10.
Higher Tc carbonyls exhibit, along with the tendency to dissociative CO replacement, also
another kind of reactivity, manifested in reactions with strong nucleophiles. This kind of reactivity
is considerably less studied, no quantitative data on the reaction kinetics have been obtained, andthe reaction mechanism is insufficiently understood. However, in this case there is no anomaly inthe behavior of the hexacarbonyl cation. This cation, being very inert in CO replacement with weak
nucleophiles such as CH3CN, which probably occurs by the dissociative mechanism, appears to behighly reactive toward stronger nucleophiles such as OH– ion [4]. The reaction is believed to startwith the nucleophilic attack at the carbonyl C atom. The trans effect primarily reduces the metal-toligand π-electron donation. As a result, the Tc–CO bond length increases and the carbonyl C atom
becomes more electrophilic. [TcBr(CO)5] also reacts relatively slowly with CH3CN but is very
reactive toward Et2NH. At the same time, tricarbonyl complexes with donor ligands, in which there
are no weak Tc–CO bonds, appear to be considerably more resistant to nucleophilic agents. For
example, the [Tc(CO)3(H2O)3]+ cation in alkaline solutions undergoes only protolytictransformations and olation, with the CO groups remaining intact [32]. These data, though scarceyet, suggest that the correlation between the Tc–CO bond length and its reactivity toward
nucleophiles does take place, in contrast to the correlation with the reactivity in dissociative
processes.
Some interesting correlations can also be found for the Tc–σ donor bond lengths. Let us41

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

compare pentacarbonyltechnetium halides with tricarbonyl halide complexes in which theremaining two sites are occupied by σ-donor ligands. For example, in [TcBr(CO)5] [8] theTc–Br bond is appreciably shorter [2.6123(9) Å] than in [TcBr(CO)3(en)] [12] [2.640(1) Å]. Similar
result is obtained by quantum-chemical calculations of [TcCl(CO)5] (2.478 Å) and [TcCl3(CO)3]2–(2.563 Å) [8]. Elongation of the Tc–Cl bond in the latter complex is accompanied by an appreciable
decrease in its Wiberg index (from 0.38 to 0.32). These results correlate with the physical andchemical properties of the complexes. In particular, pentacarbonyltechnetium halides behave ashydrophobic covalent molecules showing no pronounced tendency to electrolytic dissociation [6].
At the same time, when the coordination sphere contains only three CO groups with the other sites
occupied by σ-donor ligands such as H2O molecules, the complexation with halide ions is relatively
weak [33]. Furthermore, Tc pentacarbonyl halides are readily volatile [34], whereas the
ethylenediamine complex is much less volatile, despite practically the same molecular weight andsize [34], which may be due to stronger polarity of the molecule, in particular, to higher ionicity of
the Tc–Br bond.
Thus, structural studies are useful not only for identification of the newly synthesized Tc
compounds, but also for better understanding of their physical and chemical properties.
References[1] G. Bandoli, D.A. Clemente, U. Mazzi. J. Chem. Soc., Dalton Trans. 373 (1978).
[2] N. de Vries, J.C. Dewan, A.G. Jones, A. Davison. Inorg. Chem. 27: 1574 (1988).
[3] M.F. Bailey, L.F. Dahl. Inorg. Chem. 4: 1140 (1965).
[4] G.V. Sidorenko, A.E. Miroslavov, M.S. Grigor’ev, V.V. Gurzhiy, A.A. Lumpov,
V.A. Mikhalev, D.N. Suglobov. Radiokhimiya 53 (1): 42 (2011).
[5] B. Kanellakopulos, B. Nuber, K. Raptis, M.L. Ziegler. Z. Naturforsch. 46b: 55 (1991).
[6] V.V. Gurzhiy, A.E. Miroslavov, G.V. Sidorenko, A.A. Lumpov, S.V. Krivovichev, D.N.
Suglobov. Acta Crystallogr. E64: m1145 (2008).
[7] M.S. Grigor’ev, A.E. Miroslavov, G.V. Sidorenko, D.N. Suglobov. Radiokhimiya 39 (3): 204(1997).
[8] G.V. Sidorenko, V.V. Gurzhiy, A.E. Miroslavov, O.V. Sizova, S.V. Krivovichev,
A.A. Lumpov, D.N. Suglobov. Radiokhimiya 51 (3): 207 (2009).
[9] A.E. Miroslavov, A.A. Lumpov, G.V. Sidorenko, E.M. Levitskaya, N.I. Gorshkov,
D.N. Suglobov, R. Alberto, H. Braband, V.V. Gurzhiy, S.V. Krivovichev, I.G. Tana-naev. J.
Organomet. Chem. 693: 4 (2008).
[10] A.E. Miroslavov, G.V. Sidorenko, D.N. Suglobov, A.A. Lumpov, V.V. Gurzhiy,
M.S. Grigor’ev, V.A. Mikhalev. Inorg. Chem. 50: 1098 (2011).
[11] D.R. van Staveren, S. Mundwiler, U. Hoffmanns, Jae Kyoung Pak, B. Spingler,
N. Metzler-Nolte, R. Alberto. Org. Biomol. Chem. 2: 2593 (2004).
[12] N.A. Baturin, M.S. Grigor’ev, S.V. Kryuchkov, A.E. Miroslavov, G.V. Sidorenko,
D.N. Suglobov. Radiokhimiya 36 (3) 202 (1994).
[13] G.V. Sidorenko, M.S. Grigor’ev, V.V. Gurzhiy, S.V. Krivovichev, A.E. Miroslavov, D.N.
Suglobov. Radiokhimiya 52 (2): 126 (2010).
[14] P. Kurz, B. Spingler, T. Fox, R. Alberto. Inorg. Chem. 43: 3789 (2004).
[15] M. Tsutsui, C.P. Hrung, D. Ostfeld, T.S. Srivastava, D.L. Cullen, E.F. Meyer Jr. J. Am. Chem.
Soc. 97: 3952 (1975).
[16] R. Alberto, W.A. Herrmann, P. Kiprof, F. Baumgartner. Inorg. Chem. 31: 895 (1992).
[17] R. Rossi, A. Marchi, L. Magon, A. Duatti, U. Casellato, R. Graziani. Inorg. Chim. Acta 160:
23 (1989).
[18] J.E. Joachim, C. Apostolidis, B. Kanellakopulos, D. Meyer, B. Nuber, K. Raptis, J. Rebizant,
M.L. Ziegler. J. Organomet. Chem. 492: 199 (1995).
[19] M.S. Grigor’ev, A.E. Miroslavov, G.V. Sidorenko, D.N. Suglobov. Radiokhimiya 39 (3): 207(1997).
[20] R. Alberto, R. Schibli, P.A. Schubiger, U. Abram, R. Hubener, H. Berke, T.A. Kaden. Chem.
42

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Commun. 1291 (1996).
[21] T. Takayama, A. Harano, T. Sekine, H. Kudo. J. Nucl. Radiochem. Sci. 6: 149 (2005).
[22] I.V. Borisova, A.E. Miroslavov, G.V. Sidorenko, D.N. Suglobov, L.L. Shcherbakova.
Radiokhimiya 33 (4): 27 (1991).
[23] A.E. Miroslavov, I.V. Borisova, G.V. Sidorenko, D.N. Suglobov. Radiokhimiya 33 (6): 14(1991).
[24] R. Alberto, R. Schibli, P.A. Schubiger, U. Abram, T.A. Kaden. Polyhedron 15: 1079 (1996).
[25] R. Alberto, R. Schibli, A. Egli, U. Abram, S. Abram, T.A. Kaden, P.A. Schubiger.
Polyhedron 17: 1133 (1998).
[26] N.A. Baturin, M.S. Grigor’ev, S.V. Kryuchkov, A.E. Miroslavov, G.V. Sidorenko,
D.N. Suglobov. Radiokhimiya 36 (3): 199 (1994).
[27] M.S. Grigor’ev, A.E. Miroslavov, G.V. Sidorenko, Yu.T. Struchkov, D.N. Suglobov, A.I.
Yanovskii. Radiokhimiya 37 (3) 193 (1995).
[28] A.E. Miroslavov, N.I. Gorshkov, M.S. Grigor’ev, G.V. Sidorenko, D.N. Suglobov.
Radiokhimiya 39 (1) 41 (1997).
[29] W.A. Herrmann, R. Alberto, J.C. Bryan, A.P. Sattelberger. Chem. Ber. 124: 1107 (1991).
[30] K. Raptis, B. Kanellakopulos, B. Nuber, M.L. Ziegler. J. Organomet. Chem. 405: 323 (1991).
[31] A.E. Miroslavov, G.V. Sidorenko, A.A. Lumpov, V.A. Mikhalev, D.N. Suglobov.
Radiokhimiya 51 (1): 6 (2009).
[32] N.I. Gorshkov, A.E. Miroslavov, A.A. Lumpov, D.N. Suglobov. Radiokhimiya 42 (3): 213(2000).
[33] N.I. Gorshkov, A.E. Miroslavov, A.A. Lumpov, D.N. Suglobov, V.A. Mikhalev. Radiokhimiya 45 (2): 116 (2003).
[34] I.V. Borisova, A.E. Miroslavov, G.V. Sidorenko, D.N. Suglobov. Radiokhimiya 33 (6): 8(1991).

G.Sidorenko, F. Poineau and A.Miroslavov at the registration desk
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1.9.
“SOFT” CHEMISTRY METHODS APPEAR AS AN EFFECTIVE WAY FOR
PRODUCTION OF SUPERDISPERSIVE (NANO-SIZED) MATERALSBASED ON Re AND D-ELEMENTS OF V-VIII GROUPS.
D.V. Drobot1, O.V. Chernyshova1, O.S. Kriyzhovets1, K.A. Smirnova1, I.V.Mazilin1, A.V.
Shevelkov2, M.V. Tsodikov3, A.V. Chistyakov3, O.V.Petrakova1, E.G. Il’in4.
1

Moscow State Academy of Fine Chemical Technology, Moscow, Russia, . Pr.Vernadskogo86,119571 Moscow,
Russia e-mail dvdrobot@mail.ru, oxcher@mail.ru
2
Lomonosov Moscow State University, Moscow, Russia
3
A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Science, Moscow, Russia
4
N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Science, Moscow, Russia.

Key words: rhenium, alkoxides, synthesis, thermal decomposition, materials.
Abstract.
The paper represents a listing of results obtained by developing the original methods of controlled
synthesis of cluster and mono-, bi- and trimetallic oxo-alkoxide derivatives of rhenium and delements of V – VIII groups. The developed techniques of the synthesis of metal alkoxides include:
1) anodic dissolution of the metals in the alcohol media; 2) direct reaction of the rhenium (VII)oxide with alkoxide derivatives of the transition elements.
By such techniques were obtained tetranuclear rhenium cluster alkoxocomplexes: Re4O4(OEt)12,
Re4O6(OiPr)10; individual rhenium alkoxocomplexes with variable ratio of oxo- and alkoxo-ligands
Re4O2(OMe)16, Re4O6(OMe)12, Re4O6-y(OMe)12+y; bimetallic rhenium, molybdenum or tungsten
alkoxocomplexes ReMoO2(OMe)7, Re4-xMoxO6-y(OMe)12+y, Re4-xWxO6-y(OMe)12+y; bimetallic
rhenium, niobium or tantalum alkoxocomplexes Nb2(OMe)8(ReO4)2, Ta2(OMe)8(ReO4)2,
Nb4O2(OMe)14(ReO4)2, Ta4O2(OMe)14(ReO4)2, Nb4O2(OEt)14(ReO4)2, Ta4O2(OEt)14(ReO4)2;
trimetallic rhenium, niobium or tantalum alkoxocomplexes: Nb2-xTax(OMe)8(ReO4)2, Nb4xTaxO2(OMe)14(ReO4)2, Nb4-xTaxO2(OEt)14(ReO4)2. All compounds mentioned above arecharacterized with X-ray single crystal study, IR – spectroscopy, DTG.
It has been shown, that thermal decomposition of alkoxide derivatives in inert or hydrogen
atmosphere leads to formation nano- size powders of individual rhenium and its alloys at low
temperature. Thermal decomposition in air leads to formation individual metal oxides or its solid
solutions.
It has been demonstrated that the alkoxide derivatives could be promising precursors for next
generation catalysts manufacturing.
This paper presents review of the results obtained at Moscow State University of the Fine Chemical
Technologies and Swedish University of Agriculture Science.
The interest in rhenium alkoxides is caused by the possibility of their application as precursors forthe preparation of highly reactive fine (up to to nanoscale ) powders of rhenium metal or its alloys
with refractory metals at very low temperature ( below 500oC ) [1, 2]. The principal application ofrhenium is the production of structural alloys with various refractory metals, in particular with W,
Mo, Nb, Ta, Ni . Recently demonstrated applications of rhenium oxides, as selective catalysts inmany oxidation reactions in organic synthesis and in complete oxidation of the car exhaust gases
have made the alkoxide derivatives also attractive for the synthesis of rhenium-based oxide
nanocomposite [1-5].
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This manuscript is devoted generalization of the data on synthesis of cluster, heterometallic andheteroligand alkoxides of rhenium, discussion of their molecular structures and properties. Using
these compounds as precursors is the approach to obtain functional materials. Precursors design
allows realize its main advantage: obtaining compounds of a specified metals ration which is
required for synthesis of a target product.
The development of the preparation methods for the Re-containing materials ( alloys with refractory
metals, simple and complex oxides and so on ) implies the solution of the following problems:
Search for and development of methods for the synthesis of rhenium alkoxides and oxoalkoxide
derivatives, including cluster and heterometallic ones;
Study of their physicochemical properties including the structure in the solid state and the thermal
decomposition processes;
Determination of the chemical and phase compositions of the products of thermal decomposition ofrhenium alkoxides and oxoalkoxide derivatives under various conditions and the search for rational
applications of the materials produced in this way. Fig.1 illustrates
main ideas of theinvestigation and Fig.2 illustrates overwiew of the employed methods for the Re-containing
compounds synthesis. We participated in the development of the two approaches to the preparationof alkoxides, namely, reactions using rhenium ( V11) oxide and the electrochemical method.
A number of studies [6,7,8-10]. have demonstrated that the reaction of Re2O7 with metal alkoxides(Mo, W, Nb, Ta) is an efficient way for the synthesis of heterometallic alkoxides. Thus, trimetallic
rhenium-containing compounds were obtained for the first time.

Fig.1.The procedure of preparation of Rhenim based ultro-dispersed materials

One more approach to the synthesis of rhenium alkoxides is based on electrochemistry. Thismethod consist of anodic dissolution of metals in required alcohol. The first data on the applicationof this method to rhenium derivatives were published only recently [11]. This method was used toprepare the following compounds: Re4O6(OMe)12, Re4O2(OMe)16, Re4O6–y(OMe)12+y, Re4O6(OPri)10,
ReMoO2(OMe)7, Re4–xMoxO6–y(OMe)12+y, and Re4–xWxO6–y(OMe)12+y [6,11-14]. In the synthesis of45

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rhenium alkoxides, lithium chloride is used as a conductive additive. The process is carried out inwater-cooled cell equipped with a reflux condenser at an electrolyte temperature of 15—50 °C.
Crystallization from the electrolyte obtained by anodic dissolution of rhenium in alcohols affords
individual Re compounds. Bimetallic derivatives were prepared by the successive anodic dissolution of two metals or by dissolution of metal alkoxide.

1.
Electrochemical
synthesis(anodic dissolution of
metals in alcohols in thepresence of LiCl)

One metal
dissolution (Re)

Subsequentdissolution of several
metals(Mo-Re, W-Re)

monometallic derivatives
Re4O6(OMe)12
Re4O2(OMe)16
Re4O6-y(OMe)12+y
Re4O4(OEt)12
Re4O6(OPr-i)10
bimetallic derivatives
ReMoO2(OMe)7 (V),Re4-xMoxO6-y(OMe)12+y (VI),Re4-xWxO6-y(OMe)12+y (VII)bimetallic derivatives
Mo2O2(OMe)8 or
W2O2(OMe)8

Re4-xMoxO6-y(OMe)12
Re4-xWxO6-y(OMe)122.

bimetallic derivatives

Interaction of Re2O7 withmetal alkoxides

Nb2(OR)10 or
Ta2(OR)10

Nb2(OMe)8(ReO4)2,
Nb4O2(OR)14(ReO4)2,
Ta2(OMe)8(ReO4)2,
Ta4O2(OR)14(ReO4)2

Nb2(OR)10 and
Ta2(OR)10

trimetallic derivatives

R= Me, Et or Pri

NbxTa2-x(OMe)8(ReO4)2,
NbxTa4-xO2(OR)14(ReO4)2

Fig.2. Synthetic approaches to rhenium-containing alkoxide derivatives

The variation of the electrochemical parameters of the process carried out in an undivided cell also
allowed the researchers to obtain crystals with variable composition, namely, ReV and ReVI derivative,
Re4O6–y(OMe)12+y . The electrolysis in a divided cell (i.e., under conditions suppressing the cathodic
reduction of rhenium derivatives) gave the rhenium(VI) complex Re4O6(OMe)12.
An important factor affecting the properties of mono- and heterometallic alkoxides is theirassociation and condensation through the formation of bridging alkoxy or oxo ligands, respectively.
The association and condensation involving rhenium(V) derivatives results in tetranuclear species
Re4O6–y(OMe)12+y containing rhenium simultaneously in different oxidation states (+6 and +5). This
type of process ensures the formation of compounds with isomorphous replacement of atoms
having similar properties. When binuclear complexes of rhenium and other metals (for example,[MoO(OMe)4]2, ReMoO2(OMe)7, and [WO(OMe)4]2) are simultaneously present in a solution indifferent ratios, compounds Re4–xMoxO6–y(OMe)12+y and Re4–xWxO6–y(OMe)12+y containing both
metals are formed. The central fragment of the complexes Nb4–xTaxO2(OMe)14(ReO4)2 composed offour niobium/tantalum atoms is formed upon condensation of the starting binuclear
niobium/tantalum derivatives due to the formation of oxo bridges.
An important aspect of practical application is that the methods developed for the synthesis of biand trimetallic alkoxides allow one to obtain specimens with a pre-specified ratio of metals.This
opens up the way for deliberate action on the composition and properties of materials.
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The structure of rhenium alkoxides is shown in Fig. 3 [4].
abFig.3. Structure of rhenium alkoxides: Re3(OR)9 (R = Pri, CH2But) (a); Re2(OMe)10 (b); Re2O3(OMe)6 (c);ReMoO2(OMe)7 (d); Re4O6(OMe)12 (M = Re), Re4–xMoxO6(OMe)12 (M = Re, Mo), Re4–xWxO6(OMe)12 (M =Re, W) (e); Re4O6(OPri)10 (f ); Nb2(OMe)8(ReO4)2 (M = Nb), Ta2(OMe)8(ReO4)2 (M = Ta), Nb2–xґTaxґ(OMe)8(ReO4)2 (M = Nb, Ta) (g); Nb4O2(OMe)14(ReO4)2 (M = Nb), Ta4O2(OMe)14(ReO4)2 (M = Ta), Nb4–
xTaxO2(OMe)14(ReO4)2 (M = Nb, Ta) (h).

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Association or condensation of metal complexes in lower oxidation states may give metal-metalbonds. The structural criterion for the formation of these bonds is that the metal-metal distance iscomparable with or shorter than that in the structure of the corresponding metals [15], or shorter
than twice the effective metallicradius, which is 2,76 for Re (Tabl.1) [16-19].
Table 1. Characteristics of metal-metal bonds in alkoxide compounds
Compoundr(M–M), ÅM–M bond order

Refs.

Re4O6-y(OMe)12+y

3,45; 3,65

no bond*

Re4O4(OEt)12

2,54(2);
2,648(19); 2,65(2)

>1,
~1

*

Re4O6(OPri)10

2,5204(7) - 2,5501(5)>1*

ReMoO2(OMe)7

2,658(2)1*

Re2O3(OMe)62,559(1)1[16]

Re2(OMe)10

2,5319(7)2[17]

Re3(OPri)9

2,36

2

[18]

Re3(OCH2But)92,365(1) - 2,372(1)

2

[19]

* Own data

The structure of ReMoO2(OMe)7 [7] is composed of two distorted MO6 octahedra (M = Re or Mo)
with a common face and terminal oxo ligands (M—M bond). The distribution of the atoms of two
metals among the crystal positions is random and partially ordered, the populations being 0.71(1) Re+ 0.29(1) Mo and 0.29(1) Re + 0.73(1) Mo.
The structure of the isopropoxide complex, Re4O6(OiPr)10 (Fig.3), contains a planar rhombus of
metal atoms with all five bonds of essentially the same length (2.52 – 2.55 Å [20], compare Re=Re
2.532 Å in Re2(OMe)10 [21]) – rather short for the very low number of the electrons available forbonding in that structure (6 electrons for 5 bonds). The structure of Re4O4(OEt)12 contains also aplanar Re4-core close to a rhombus in its geometry . It belongs as well as the structure of theoxoisopropoxide derivative to the well-known M4X16 core type structure type, originating fromhexagonal dense packing of metal and ligand atoms, one of the most typical for metal alkoxides [22,23]. Two additional electrons available for bonding do not lead to pronounced shortening of the ReRe distances, on contrary, the structure of the compound Re4O4(OEt)12 contains only two shorter
symmetrically equivalent bonds (2,54(2) Å Re(1)–Re(2)), which is comparable with the length of adouble Re=Re bond. The other two symmetrical bonds and the shorter diagonal of the rhombus
have almost the same lengths and are considerably longer (2,65 Å). These values are considerably
higher than even the single Re–Re bond length in Re2О3(OMe)6 (2,56 Å ), where the metal atoms aswell as in Re4O4(OEt)12 are connected by both oxo- and alkoxobridges.
The structure of Re4O6(OPri)10 [7,13] contains four ReO6 octahedra connected by common edges
and five Re—Re bonds with a higher order. The metal atoms are located in one plane and areconnected by two µ3- and four µ2-oxo bridges.
The compound Re4O6(OPri)10 is of interest as regards the metal—metal bonds. In this structure, theRe—Re distances, equal to 2.5204(7)—2.5501(5) Е, are comparable with the length of a localized
Re—Re bond with a higher order (see Table I). Since two Re atoms in this complex occur in +5
oxidation state and the other two atoms, in +6 oxidation state, there are six electrons available for

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their binding to each other. Clusters similar to Re4O6(OPri)10 with five virtually equal metal—metal
distances have been found previously[24,25]. only in a system with ten electrons (Table 2).
Table 2. Metal–Metal Bonds in clusters based on Ti4(OMe)16 core structure

Compound

L.1, Å

L.2, Å

D, Å

Number of corecluster electrons

Ref.

Ba1,14Mo8O16

2,616(1)2,578(1)2,578(1)10[24]Ba1,14Mo8O162,847(1)2,546(1)2,560(1)8,28 (average)[24]

W4(OEt)16

2,936(2)2,646(2)2,763(1)8[25]

Re4O4(OEt)12

2,54(2)

2,648(19)2,65(2)8[*]

Re4O6(OPr-i)10

2,5501(5)2,5399(5)2,5204(7)6[*]

Mo4O8(OPr-i)4(Py)4

3,472(1)2,600(1)3,218(1)4[25]* Own data
The structure of tetranuclear rhenium methoxy derivatives Re4O6–y(OMe)12+y and related bimetallic
complexes is based on planar Re4 fragment. The structure of Re4O6–y(OMe)12+y [6,11] ischaracterized by the ReO6 ocrahedra sharing edges and faces; the rhenium atoms occupy thevertices of a nearly regular quadrangle and are bound alternately by oxo bridges and double alkoxy
bridges. No metal—metal bonds are present. When y = 0, one terminal oxo ligand per rhenium atom
is present, while for y = 4, the structure does not contain terminal oxo ligands. For 0 < y < 4, theseoccur in the statistic disorder with alternative methoxy groups (i.e., the crystals are built by joint
packing of molecules containing different numbers of oxo and alkoxy groups).
The structure of Re4–xMoxO6–y(OMe)12+y [6] is similar to that of Re4O6–y(OMe)12+y. Some rhenium
atoms are replaced by molybdenum atoms in the isomorphous manner. The distribution of the metal
atoms of two sorts among the positions is random and partially ordered (from 0.83(2) Re + 0.17(1)Mo to 0.98(2) Re + 0.02(2) Mo for the crystal with x = 0.4). The structure of the derivative Re4–
xWxO6–y(OMe)12+y is similar to that of Re4–xMoxO6–y(OMe)12+y.
Bi- and trimetallic derivatives of rhenium, niobium, and tantalum exist as two structures containing
perrhenate groups. One is based on M2(OMe)10 (M = Nb or Ta) and the other, on fragments
consisting of four metal atoms. In the complex Nb4–xTaxO2(OMe)14(ReO4)2, [7-10] four niobium (ortantalum) atoms form a fragment resembling the structure of Re4O6–y(OMe)12+y. Trimetallic
complexes are formed due to isomorphous replacement of niobium atoms by tantalum. The distribution of the metal atoms of two sorts among the positions is statistic, partially ordered (for the crystal
with x = 2, the populations of the position connected to the ReO4 group are (0.70±0.05) Nb +(0.30±0.05) Ta; for the other position, (0.29±0.05) Nb + (0.71±0.05) Ta).
Isomorphous replacement of atoms with similar properties affords crystalline complexes withvariable composition in which the ratio of the two metals can be varied over a broad range.
For example, the replacement of rhenium by molybdenum or tungsten gives rise to rhenium-based
tetra-nuclear complexes Re4–xMoxO6– y (OMe)12+ ,; (0 <x< 2.82) and Re4–xWxO6–y(OMe)12+y (0 < x < 2)
[6,14]. Since tetranuclear structure is not encountered for individual molybdenum or tungsten
derivatives, in this case, the isomorphous replacement of rhenium by these metals is possible only
in a limited range of compositions.
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In the case of Nb4–xTaxO2(OMe)14(ReO4)2 and Nb2–x-Tax-(OMe)8(ReO4)2, the Nb : Ta ratio
susceptible for isomorphous replacement of niobium by tantalum is boundless. The bimetallic
niobium/rhenium (х = 0, x' = 0) and tantalum/rhenium complexes (х = 4, x' = 2) as well as
trimetallic complexes with a variable composition (0 < x < 4, 0 < x' < 2)[7-9] have been prepared.
Studies of the thermal properties of rhenium alkoxides have shown that they decompose at relatively
low temperatures (100—300 °C) yielding either oxide or metal phases, depending on the process
conditions (Fig.4). [7,8,12].

Monometallic derivatives
Re4O6(OPri)10
Re4O2(OMe)16
Re4-xO6-y(OMe)12+y
Re4O6(OMe)12
Re2O3(OMe)6Bi- and trimetallic
derivatives
Re4-xMoxO6-y(OMe)12+y
Re4-xW xO6-y(OMe)12+y
ReMoO2(OMe)7
Nb4-xTaxO2(OMe)14(ReO4)2
Nb2-x'Tax'(OMe)8(ReO4)2

in hydrogen

Metals and alloys
powders
Nanosized Rhenium
powders,
Re–Mo alloys (sigmaphase, solid solutions
based on Re and Mo),
alloys Re–W

atmosphere
THERMAL TREATMENT(150 - 900°С)

in air or inert
atmosphere

INCORPORATION
INTO INERTMATRICES

Individual oxides
ReO3 (cub.)ReO2 (monocl.)
Oxide solid solutions
and complex oxides(Re,Mo)O2 (o-rh.),(Re,Mo)O2 (tetr.),(Re,W)O3 (cub.),
Phases of systems
Re–Ta(Nb)–O based on
L-Ta2O5 structure
Catalytic materials

Fig.4. Alkoxides as a basis for fabrication of rhenium-containing materials

Decomposition of individual rhenium alkoxides Re4O6(OPri)10, Re4O2(OMe)16, Re4–xO6–y(OMe)12+y,and Re4O6(OMe)12 in air or in an inert atmosphere affords rhenium oxides, ReO3 or monoclinic
ReO2, as highly dispersed powders with an average particle size of less than 30—50 nm.. Similar
decomposition of the bimetallic derivatives Re4–xMoxO6–y(OMe)12+y and Re4–xWxO6–y(OMe)12+y yields
single-phase specimens of rhenium/molybdenum (Re,Mo)O2 or rhenium/tungsten (Re,W)O3 solid
solutions. By decomposition of bi- and trimetallic rhenium, niobium, and tantalum derivatives,complex oxide phases of the Re—Ta(Nb)—O systems based on a block type structure derived from
L-Ta2O5 were prepared for the first time (Table 3).
Table 3. Structure of (Nb1-xTax)4O2(OMe)14(ReO4)2 (х = 0,3; 0,5; 0,7) and termal properties№
Source complex
Product
а, Ă
b, Ă
c, Ă
1*
2*
3*
4**
5**

V, Ă3

(Nb0,7Ta0,3)4O2(OMe)14(ReO4)2 (Nb0,7Ta0,3)2O5 6,18(6) 40,25(6)=11×3,659 3,922(2) 975,1(17)(Nb0,5Ta0,5)4O2(OMe)14(ReO4)2 (Nb0,5Ta0,5)2O5 6,18(6) 40,31(5)=11×3,665 3,918(18) 975,9(16)(Nb0,3Ta0,7)4O2(OMe)14(ReO4)2 (Nb0,3Ta0,7)2O5 6,177(10) 40,29(10)11×3,663 3,909(3) 973(3)L(γ)–Ta2O5 (ICCD–JCPDS № 25–0922)
L(γ, T)–Nb2O5 (ICCD–JCPDS № 27-1313)* Experiment

6,198(5) 40,29(3)=11×3,663 3,888(5)6,168(1) 29,312(1)=8×3,664 3,938(1)

970,9
712,0

** Literature data

Phase composition of the products obtained by thermal decomposition of (Nb1-xTax)4O2(OMe)14(ReO4)2(х = 0,3; 0,5; 0,7) in air
50

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011выход, % массDecomposition of alkoxide in a hydrogen atmosphere allows one to prepare nano-sized powders ofrhenium metal (from individual derivatives) or rhenium alloys (from the bimetallic complexes Re4–
xMoxO6–y(OMe)12+y, and Re4–xWxO6–y(OMe)12+y).
Rhenium alkoxides proved to be promising starting materials for the development of catalysts byinsertion into a zeolite matrix. In particular, mono- and bimetallic rhenium alkoxides Re2O3(OMe)6and ReMoO2(OMe)7 ( it is cluster compound ) have been used to prepare new-generation catalysts
by insertion of these compounds into a NaY zeolite matrix followed by their thermal
decomposition. A substantial advantage of this approach is the possibility of preserving the highdispersed state via stabilization of clusters, including those containing two different metals, in thezeolite cavities. Decomposition of the alkoxides inserted in the matrix affords metal or oxide
nanoclusters whose mobility is restricted inside the pores. In the case of bimetallic systems, it ispossible to obtain, directly in the pores,
highly dispersed particles uniform not40
only in their size but also in their
35
composition, which is pre-specified by
the ratio of the metals in the initial
30
compound. A study of the catalytic
25
properties of the materials obtained by20
this method showed a substantial
positive synergistic effect for the
15
product of insertion of the bimetallic
10
complex compared with the materials
based on individual rhenium and5
molybdenum compounds. [26] This has
0been confirmed when using bimetallic
Ta
Re
W
Re-W
Re-Ta
(Re-W, Re-Ta) alkoxoderivatives asprecursors in the production of catalysts Fig.5. The relationship between alkane-olefins fractions C5 –C9 yield and composition of active components in crossfor the reactions of alcohol reductive
coupling reaction of ethanol and glycerin.
dehydration (Fig. 5) [27].
Conclusion.
The traditional method for alkoxide synthesis is based on ligand substitution reactions. This method
was used to prepare individual rhenium alkoxides. Alternative synthetic routes include reactions ofrhenium(VII) oxide with alcohols and alkoxides of other metals and anodic disso- lution of metals
in alcohols. These methods made it possible to synthesize both known and new monometallic
rhenium alkoxides and also to synthesize for the first time bi- and trimetallic rhenium,
molybdenum, tungsten, niobium, and tantalum complexes. The isomorphous replacement of metals
in bi- and trimetallic derivatives opens up the way to the alkoxide derivatives with variable composition, in which the ratio of the metals can be varied over a broad range.
An important structural feature of alkoxides and oxoalkoxides is the presence of alkoxy and oxo
bridges, which ensure the formation of polynuclear (in particular, heterometallic) compounds.
Acknowledgements.
The authors show their gratitude to professors G.A. Seisenbaeva and V.G. Kessler(Department of Chemistry SLU, Uppsala, Sweden) for creative collaboration on the different stepsof the work and to the RFBR (projects 06-03-32444 and 09-03-00328) for the financial support.
References.
1. R. H. Tuffias, R. B. Kaplan, and M. A. Appel, Proc. Int. Symp: "Rhenium and Rhenium Alloys"(Orlando, Florida (USA), 1997).
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

2. R. W. Broomfield, D. A. Ford, H. K. Bhangu, M. C. Thomas, D. J. Frasier, P. S. Burkholder, K.
Harris, G. L. Erickson, and J. B. Wahl: Proc. Int. Symp. "Rhenium and Rhenium Alloys"(Orlando, Florida (USA), 1997).
3. M. A. Ryashentseva and Kh. M. Minachev: Renii i ego soedineniya v geterogennom katalize[Rhenium and its Compounds in Heterogeneous Catalysis] (Nauka, Moscow, 1983).
4. P. A. Shcheglov, D. V. Drobot (2005). Russian Chemical Bulletin.International Edition. 54,
2247.
5. A. A. Palant, I. D. Troshkina, A. M. Chekmarev : Metallurgy of rhenium (Nayka, Moscow,
2007).
6. G. A. Seisenbaeva, A. V. Shevelkov, J. Tegenfeldt, L. Kloo, D. V. Drobot, and V. G. Kessler(2001). J. Chem. Soc., Dalton Trans. 2762.
7. D. V. Drobot, P. A. Shcheglov, G. A. Seisenbaeva, and V. G. Kessler (2002). Izv. Vuzov.
Tsvetnaya metallurgiya [Higher School Bull. Nonferrous Metallurgy]. 6, 32.
8. P. A. Shcheglov, D. V. Drobot, G. A. Seisenbaeva, S. Gohil, and V. G. Kessler (2002). Chem.
Mater. 14, 2378.
9. P. A. Shcheglov, G. A. Seisenbaeva, S. Gohil, D. V. Drobot, and V. G. Kessler (2002).
Polyhedron. 21, 2317.
10. Pat. RF 2227788 (Byul. Izobret., 2004), 12.
11. V. G. Kessler, A. V. Shevelґkov, G. V. Khvorykh, G. A. Seisenbaeva, N. Ya. Turova, and D. V.
Drobot (1995). Zh. Neorgan. Khim. 40, 1477.
12. P. A. Shcheglov, D. V. Drobot, Yu. V. Syrov, and A. S. Malґtseva (2004). Neorgan Materialy.
40, 220.
13. P. A. Shcheglov, G. A. Seisenbaeva, D. V. Drobot, and V. G. Kessler (2001). Inorg. Chem.
Commun.. 4, 227.
14. G. A. Seisenbaeva, A. V. Shevelґkov, V. G. Kessler, N. N. Belanishvili, and D. V. Drobot(1999). Zh. Neorgan. Khim. 44, 383.
15 F. A. Cotton and R. A. Walton: Multiple Bonds Between Metal Atoms (J. Wiley and Sons, New
York—Chichester, 1982).
16. P. G. Edwards, G. Wilkinson, M. B. Hursthouse, K. M. Abdul Malik (1980). J. Chem. Soc.
Dalton Trans. 2467.
17. J. C. Bryan, D. R. Wheeler, D. L. Clark, J. C. Huffman, A. P. Sattelberger (1991). J. Am. Chem.
Soc. 113, 3184.
18. D. M. Hoffman, D. Lappas, D. A. Wierda (1993). J. Am. Chem. Soc. 115, 10538.
19. W.-W. Zhuang, B. E. Truitt, D. M. Hoffman (1997). Inorg. Chem. 36, 3330.
20. G.A. Seisenbaeva, A.I. Baranov, P.A. Shcheglov, V.G. Kessler (2004). Inorg. Chim. Acta. 357,
468.
21. J. C. Bryan, D. R. Wheeler, D. L. Clark, J. C. Huffman, A. P. Sattelberger (1991). J. Amer.
Chem. Soc. 113, 3184.
22. D.A. Wright, D.A.Williams (1968). Acta Crystallogr. 24, 1107.
23. N. Ya Turova., E. P. Turevskaya., V. G. Kessler, M. I. Yanovskaya: The Chemistry of Metal
Alkoxides (Boston, Dordrecht, London: Kluwer Academic Publishers. 2002).
24. C. C. Torardi, R. E. McCarley (1981). J. of Solid State Chem. 37, 393
25. M. H. Chisholm, J. C. Huffman (1981). J. Amer. Chem. Soc. 103, 6093
26. A. L. Kustov, V. G. Kessler, B. V. Romanovsky, G. A. Seisenbaeva, D. V. Drobot, and P. A.
Shcheglov (2004). J. Mol. Catal. A. 216, 101.
M.V. Tsodicov, A.V. Chistyakov, F.A. Yandieva, V.Ya. Kugel, O.V. Buhtenko, T.A.
Zhdanova, A.E. Gehman, I.I. Moiseev, D.V. Drobot, O.V. Petrakova. Patent 2391133 RF, MPK С1
B01J 21/04, B01J 23/30, B01J 23/36, C07C 1/20, C07C 9/16, C07C 9/00, C07C 11/00. Method ofalkano-olefin hydrocarbon production – № 2008139448/04, applied for 06.10.08; published10.06.10, Bull. № 16.
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1.10.
STRUCTURE AND MAGNETIC PROPERTIES OF POLYNUCLEARCOMPLEXES CONTAINING Re(IV)Carlos Kremer, Raúl Chiozzone
Cátedra de Química Inorgánica, Facultad de Química,
Montevideo, Uruguay, (e-mail: ckremer@fq.edu.uy)

One of the major goals in inorganic supramolecular chemistry today is the design of polynuclear
coordination arrays and the study of their magnetic properties. With the generation of well-definedarchitectures it is possible to understand the different factors which determine the exchange
coupling between spin carriers. Most of the results found in the literature are focused onpolynuclear complexes containing metal ions belonging to the first transition series. With thisinformation the study of those systems containing 4d or 5d metal ions becomes very interesting. In
this presentation we revise the structure and magnetic properties of Re(IV) mononuclear andpolynuclear complexes.

Fig. 1. Some Re(IV) mononuclear complexes
used as building blocks.

Rhenium(IV), a 5d3 ion with a 4A2g electronic ground state, usually forms octahedral complexes
which are reasonably stable against redox processes and inert to ligand substitution. Complexes
containing dicarboxylic ligands, [ReX4(ox)]2- and [ReX4(mal)]2- (X = Cl, Br; ox = oxalate; mal =malonate), N-donor ligands, [ReCl5(pyz)]- (pyz = pyrazine), [ReBr5(Hpyzc)]- (Hpyzc = 2pyrazinecarboxylic acid), and [ReCl4(CN)2]2-, are some examples of mononuclear rhenium
complexes that have been prepared and fully characterized. The presence of ligands which can act
as donors toward a second metal ion (Fig. 1) is a common structural feature that has allowed the"complex as ligand" approach for the design of higher nuclearity compounds. Their structures range
from discrete binuclear complexes (for example in [ReCl4(-ox)Mn(dmphen)2], dmphen = 2,9dimethyl-1,10-phenanthroline)) to extended chain-like compounds (for example in [ReCl4(mal)Mn(dmphen)(H2O)2]) are presented in this work. In addition, the magneto-structural studies ofthese mono- and polynuclear complexes are also discussed.

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1.11.
POLYFLUORINATED β-DIKETONATES OF RHENIUM
A.I. Irtegov1, M.A. Kurykin2, V.N. Khrustalev2, E.E. Nikishina1,
D.V. Drobot1.
1

Lomonosov’s Moscow State Academy of Fine Chemical Technology, Moscow, Vernadskogo avenue 86,
2
A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences,
Moscow, Vavilov st., 28.
irteg@mail.ru, mak@ineos.ac.ru

Fluorinated β-diketonates of metals possess a number of properties useful for technology, themost valuable properties are good solubility in organic solvents and high volatility. Therefore they
can be used for solving two important problems: preparation of catalysts and film coatings by
CVD. In recent years rhenium has become one of the most in-demand metals for both these
problems.
We have prepared the earlier described complex ReOCl2(OEt).2PPh3 and studied its reactions
with-diketones

HL(CH3COCH2COCH3,

CF3COCH2COCF3,C2F5COCH2COC2F5,

C3F7COCH2COC3F7, C4F9COCH2COC4F9, C3F7OCF(CF3)COCH2COCF(CF3)OC3F7). A number of
new rhenium complexes ReCl2L.2PPh3 were obtained. We have studied thermal properties andspectral characteristics of the synthesized compounds. The fluorinated rhenium complexes wereshown to have high volatilities and vaporize without decomposition, this can be used in preparationof rhenium-containing films.
The details of the synthesis and physicochemical properties of the complexes will beconsidered in the presentation.
The work was financially supported by the Russian Foundation for Basic Research (Grant no.
09-03-00328а).

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1.12.
PREPARATION OF TECHNETIUM METAL-METAL BONDED ACETATEDIMERS VIA HYDROTHERMAL ROUTE
W.M. Kerlin1, T. Yordanova2, F. Poineau1, P.M. Forster1,
A.P. Sattelberger3, K.R. Czerwinski1
1

Department of Chemistry, Radiochemistry Program, University of Nevada Las Vegas,
Las Vegas, NV 89154, USA
2
Laboratory for Computational Molecular Design, Ecole Polytechnique Fédérale de Lausanne,
Lausanne, ch-1015, Switzerland
3
Energy Engineering and Systems Analysis Directorate, Argonne National Laboratory,
Argonne, IL 60439, USA

Recent results of hydrothermal reactions with pertechnetate, Tc(VII), have produced
various low-valent compounds such as dication hexahalotechanate (IV) and Tc-Tc dimers.
The reaction of potassium pertechnetate in acetic acid /hydrochloric acid in an atmosphereof hydrogen gas yields red hexagonal crystals of known tetraacetatodichloro ditechnetate(III),Tc2(μ-O2CCH3)4Cl2 and blue triacetatodiaquadichloro ditechnetate (II)(III) hydrate.
Single crystal XRD analysis on both Tc dimers has been determined and the unit cellparameters will be presented.
Additional characterization of the Tc2(μ-O2CCH3)3Cl2(H2O)2·H2O including UV-Vis, and
FT-IR will shown. DFT calculations will be given for the Tc2(μ-O2CCH3)2Cl4 Tc2(μO2CCH3)3Cl2(H2O)2·H2O, and Tc2(μ-O2CCH3)4Cl2.
Currently, work explores in situ hydrogen generation via Zn or sodium borohydride, as wellas the use of alternative reducing agents, allowing for many more reactions to be carried out inconventional autoclaves.
Results of the Zn and sodium borohydride reactions will be discussed. These one step
reactions of reducing Tc(VII) to low valent technetium provides high yield intermediates forpotential waste forms and use in nuclear fuel cycle separations.
Acknowledgments: SISGR-Fundamental Chemistry of Technetium-99 Incorporated into Metal
Oxide, Phosphate and Sulfide: Toward Stabilization of Low-Valent Technetium
Contract No. 47824B Basic Energy Sciences, DOE
References:
1. L. I. Zaitseva, A.S. Kotel’nikova and A.A. Reszvov, Russ. J. Inorg. Chem. 1980, 25, 1449.
2. Cotton, A.F., C.A. Murillo, R.A. Walton.; Multiple Bonds Between Metal Atoms, Springer
Science and Business Media, Inc.: New York, 2005, p. 257-259.
3. V. I. Spitsyn, B. Baierl, S.V. Kryuchkov, A.F. Kuzina and M. Varen, Dokl. Akad. Nauk.
1981, 256, 608.

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1.13.
PHYSICOCHEMICAL PRINCIPLES OF THE DEVELOPMENT OFRHENIUM-BASED AND RHENIUM-CONTAINING ALLOYS
Povarova K.B.
Baikov Institute of Metallurgy and Materials Science RAS. povarova@imet.ac.ru

Rhenium (Re) is a hcp transition metal belonging to Group VII of the third long period of
the periodic table (atomic number 75). The melting/boiling points (3453/6173 K), density (21.04
g/cm3), and elastic modulus (479 GPa) of Re are higher than those of the most refractory metals.
The maximum operating temperature, at which the weight loss by evaporation is ≤1% per 10hours, reaches 2950 K.
Rhenium belongs to rare metals (its clark is ~10-7 - 10-6%) and is difficult to manufacture(because of strong strain hardening) and expensive metal.
The unique properties of Re and some its alloys, which can be used in the environments
impossible for operating of other materials, determine high interest in them. For example, inshort-term and long-term strength at temperatures above 2400K, Re surpasses the best hightemperature cold-brittle tungsten alloys and, unlike them, has a plasticity reserve at temperatures
down to cryogenic ones, high resistance to thermal shock and thermal cycling (290-2500K), low
gas permeability, and does not form any stable interstitial phases.
The physicochemical approaches to the design of structural alloys with Re are developed.
Use of Re as an alloying element (AE) or as an alloy base is determined by two factors: themutual solubility of Re and AE and four "rhenium effects", which have no analogs. A highsolubility of Re in bcc Group VI metals (W, Mo and Cr) has allowed the development of a newclass of high-temperature alloys and the alloys with special physical and chemical properties (WRe, Mo-Re, and W-Mo-Re), in which the addition of 25-35 at. % Re simultaneously increases
low-temperature ductility and strength of cold-short Group VI metals (“Re effect-1”).
The ability of Re to drastically increase the strain hardening rate of W and Mo alloys (“Reeffect-2”) allowed the development of the alloys with σB of up to 6000 MPa for elastic members.
A substantial increase in low-temperature ductility of W and Mo alloys at 2-7 at. % Re(“Re effect-3”) allowed the development of cost-effective high-temperature rhenium alloys forbulk products.
The ability of Re to increase the high-temperature strength and service life of modern
nickel-base superalloys is widely used as ”Re effect-4”.

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1.14.
SYNTHESIS AND CHARACTERIZATION OF LOW-VALENT BINARYTECHNETIUM CHLORIDES
E.V. Johnstone, F. Poineau, P.F. Weck, E. Kim1, P.M. Forester, B. Scott2, T. Hartmann, A.P.
Sattelberger3, K.R. Czerwinski
1

Department of Chemistry, University of Nevada Las Vegas, Las Vegas, NV 89154, USA
Department of Physics and Astronomy, University of Nevada Las Vegas, Las Vegas, NV 89154, USA
2
Materials Physics and Applications Division, Los Alamos National Laboratory,
Los Alamos, NM 87545, USA
3
Energy Engineering and Systems Analysis Directorate, Argonne National Laboratory,
Argonne, IL 60439, USA

Binary transition metal halides (BTMH) are an area of fundamental chemistry that exhibits
an array of unique chemical and physical properties. Of the Group V, VI, and VII elements, thebinary technetium halides for many years were considerably lacking in comparison with only threeisolated and characterized in the solid state (TcF6, TcF5, and TcCl4) [1]. More recently, thediscovery of TcBr4 and TcBr3 has generated interest in pursuing low-valent binary technetiumchlorides [2].
In this work two novel binary technetium halides TcCl2 and TcCl3 were synthesized inquantifiable amounts in the solid state and analyzed using various physicochemical characterization
methods including single-crystal and powder X-ray diffraction (XRD), UV-Vis, X-ray absorption
fine structure (XAFS), and elemental analysis, as well as density functional theory calculations(DFT).
Technetium dichloride was synthesized from the stoichiometric reaction of technetium metaland elemental chlorine at elevated temperatures as a novel compound with new structure-type
consisting of an eclipsed conformation of [Tc2Cl8] units containing a Tc-Tc triple bond [3].
Technetium trichloride was prepared from the reaction of Tc2(O2CCH3)4Cl2 with passing
HCl (g) at elevated temperatures and characterized as a novel compound isostructural to ReCl3 witha triangular Tc33+ core structure containing metal-metal double bonds [4]. The low-valenttechnetium chlorides synthesized exhibit new and interesting chemical structures and properties,
and even show potential as waste forms or use in separations for the nuclear fuel cycle.
Acknowledgments: SISGR-Fundamental Chemistry of Technetium-99 Incorporated into Metal
Oxide, Phosphate and Sulfide: Toward Stabilization of Low-Valent Technetium
Contract No. 47824B Basic Energy Sciences, DOE
References:
4. Schwochau, K. Technetium: Chemistry and Radiopharmaceutical Applications, Wile-VCH:
Weinheim, 2000, p. 113.
5. F. Poineau, E. Rodriguez, P.M. Forester, A.P. Sattelberger, A.K. Cheetham, and K.R.
Czerwinski, J. Am. Chem. Soc. 131, 910-911 (2009).
6. F. Poineau B.L. Scott, P.F. Weck, E.V. Johnstone, P.M. Forester, E. Kim, K.R. Czerwinski, andA.P. Sattelberger, J. Am. Chem. Soc., submitted
7. F. Poineau, E.V. Johnstone, P.F. Weck, E. Kim, P.M. Forester, B.L. Scott, A.P. Sattelberger,
and K.R. Czerwinski, J. Am. Chem. Soc. 132, 15864-15865 (2010).

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1.15.
RECENT RESULTS IN RHENIUM CLUSTER CHEMISTRY
V.E. Fedorov, Yu.V. Mironov, N.G. Naumov, K.A. Brylev
Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences,(e-mail: fed@niic.nsc.ru)

Novosibirsk, Russia

Metal cluster compounds are very interesting and important representatives in rhenium
chemistry. Authors of this paper carry out the systematic investigation of rhenium clustercomplexes during long time. The results of this study are preparation of more then two hundred of
new cluster rhenium compounds of different nuclearity - Re4, Re6, Re9, Re12, discovery of some key
cluster complexes, among of them several compounds have original crystal structures and very
interesting physical and chemical properties.
The systematic studies of tetrahedral [Re4Q4(TeY2)4Y8 (Q=S, Se, Te; Y=Cl, Br) andoctahedral Re6Q8L6 cluster compounds opened the possibility for synthesis of complexes withdiverse compositions and structures. Study of octahedral chalcocyanide complexes [Re6Q8(CN)6]4(Q=S, Se, Te) was shown that using high temperature reactions it is possible to substitute inner 3Q ligands in cluster core with formation of mixed ligand units {Re6Q8-xQ’x}. Similar reactions givethe equilibrium between different chemical forms [Re6Q8-xQ’x(CN)6]4- that is in common withclassical reactions of stepwise ligands substitution which are typical in coordination chemistry.
Experimental conditions of reactions bringing to condensation of cluster fragments into
complexes having more high nuclearity were found: for example, octahedral [Re6Se8Br6]4- andbioctahedral [Re9Se11Br6]2– complexes were prepared from triangle compound Re3Br9; andtwelvenuclear complexes with inserted carbon atom [Re12(6-C)S17(CN)6]8–/6– were synthesized in
the process of further condensation of octahedral clusters. The latter is unique complex in thecluster chemistry of transition metals.
Chalcocyanide cluster complexes [Re4Q4(CN)12]4–, [Re6Q8(CN)6]4– (Q=S, Se, Te) and[Re12CS17(CN)6]6– were studied broadly and carefully. Due to ambidentate nature of CN ligands
these complexes are very suitable building blocks in design of coordination cyano-bridge polymersof different dimensionality with structures of chain-like, layered and framework types.
The methods for synthesis of hybrid tetrahedral and octahedral complexes coordinatedorganic N- and P-donor ligands were developed. Some rhenium complexes possessing bright red
luminescence are synthesized; similar complexes are perspective preparation in procedure of photodynamic therapy. It was found that emission properties of cluster complexes may be regulated bymodification of their electron structures via substitution of inner or external ligands in complexes.
Broad studies of chemistry of rhenium cluster complexes of different compositions,
nuclearity and structures have expanded essentially a fundamental knowledge in the field of
coordination chemistry of not only rhenium but also transition metals integrally. Obtained
regularity can be used as fundamental base in design of new cluster compounds and materials withcomplex of necessary functional properties.
Acknowledgment. Authors thank Russian Foundation for Basic Research (grants N 09-0392004-HHC and 10-03-01040-а ) for financial support.

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1.16.
HETEROLIGAND ALKOXIDES OF RHENIUM CONTAINING O-Et
AND O-iPr LIGANDS
O.S. Kriyzhovets , D.V. Drobot, A.V. Shevelkov*.


Moscow State University of Fine Chemical Technologies named after M.V. Lomonosov, 119571, Russian Federation,
Moscow, prospect Vernadskogo 86, e-mail: vinilova.olka@bk.ru; dvdrobot@mail.ru*Lomonosov Moscow State University, Chemistry Department, 119071, Russian Federation, Moscow, Leninskie Gory,e-mail: shev@inorg.chem.msu.ru

Keywords: anodic dissolution, rhenium alkoxides, heteroligand alkoxides, nanopowder, extended
Huckel calculations
Abstract:
Currently homometallic and heterometallic rhenium alkoxides are already well known to science,and because of close attention to them there are practically no gaps for researchers in studying ofthat rhenium alkoxides. Existing works on this subject pointed to the lack of study and novelty ofchemical synthesis of heteroligand rhenium alkoxides. But the analysis of the literature data
revealed an extraordinary closeness of the structures of rhenium isopropyl alkoxide and ethyl
alkoxide (subsequent Re4O6(OPri)10 [1] and Re4O4(OEt)12 [2] respectively; the metal-cluster framesof them have the same structure (similar to the initial structure of Ti4(OMe)16)[3]), that enables thesynthesis of rhenium heteroligand complexes containing -O-Et and -O-iPr ligands. We reportquantum-chemical analysis of the ligand nature influence on the stability of rhenium alkoxides by
the Extended Huckel Method, the electrochemical synthesis of heteroligand complexes with generalformula Re4On(O-Et)x(O-Pri)y (at an initial molar ratio of EtOH: PriOH = 1:1; 2:1; 1:2 in theelectrolyte) and the study of physical-chemical (including thermal) properties of the heteroligand
complexes and products of their thermal decomposition by X-ray Phase Analysis, Element
Analysis, DTG, DSC and IR-spectroscopy.
Introduction:
The substantial difference between the saturated vapor pressure above Re oxides and otherrefractory metals oxides and incongruent sublimation of lower Re oxides hamper the production of
specimens with a required set of properties. This determines the relevance of the research aimed atdeveloping new methods of synthesis of rhenium-containing metallic and oxide materials. One ofpossible ways to monitor microstructure and composition of the materials is to deliberate the choiceof the starting compounds - precursors. Properties of a selected precursor and properly chosen
methods of processing allow one to control the composition and microstructure, opening the way toobtain materials with required characteristics. In many cases modern materials and designs require
strict control of the composition (0.1%) and the microstructure parameters (at the nanometers sizes)[4]. An effective approach to producing functional materials based on the d-elements (individual
nanopowders of metals, alloys and ligatures, simple and complex oxides, bimetallic catalysts) witha given set of properties and qualities is alkoxotechnology [5]. In this work we report the precursors(heteroligand alkoxides of rhenium) obtained by alkoxotechnology as well as the results of theinvestigations of the dependence of the synthesized products composition and compositions of the
product their thermal destruction upon the ratio of the initial components.
Quantum-chemical calculations:
The analysis of the previous results [1,2] shows that Re4O6(OPri)10 has an already regular cluster
frame Re4 (metal-metal bond Re-Re= 2.52-2.55 Å), whereas Re4O4(OEt)12 possesses a distorted
structure of the cluster frame evidenced by the metal-metal bond length (Re-Re=2.54-2.65 Å). Due59

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to the closeness of their structures the possibility to produce heteroligand complexes based on one
or another structure with probable substitution of a certain number of ligands clearly exists. For
preliminarily estimation of the possible existence of heteroligand rhenium alkoxides, the quantumchemical calculations were performed using the Extended Huckel approach realized by the CACAO
program package. To facilitate calculations, the –CH3 and –CF3 radicals were used instead of –C2H5
and –СH2CF3 ones (as simplified analogues). The findings can not be used as referenced data andwere employed only for the comparative analysis.

First of all, we compared the Re4 cluster for both structures,
Re4O6(OPri)10 and Re4O4(OEt)12 (Tab.1). This data enables ananalysis of energy states for clusters [Re4]22+ and [Re4]20+ ofcomplexes Re4O6(OPri)10 and Re4O4(OEt)12 correspondingly (thatcomes to agreement with the number of cluster electrons in eachstructure). The analysis of the diagrams of molecular orbitals markedout 6 bounding molecular orbitals in each case. That is evidenced by
the analysis of the boundary surfaces of the atomic d-orbitals ofrhenium atoms comparatively to each other. (Fig.1). These results
Fig.1. Diagram of theagree nicely with the data described earlier in the literature for theboundary
surfacesofsystem with 8 cluster electrons ([Re4]20+). Calculations for both C2hatomicd-orbitalsofand D2h symmetries were performed with different number of cluster
rhenium
atoms electrons (6 and 8). However, only insignificant differences between
comparatively to each the energy states of two structures were observed. Thus a cluster withother in the [Re4]20+ with the cluster frame Re4 can exist with slight geometry variations
the 8 cluster electrons.
meaning that compounds with variable geometry and composition canbe prepared; moreover, the formation of complexes based on
isopropyl alkoxide structure and on ethyl alkoxide structure is equally probable. On the next stagesof the calculations only the C2h symmetry was used since this provides the way to simplify theprocess of adding the radicals into the cluster system. 4 µ2-O and 2 µ3-O ligands were used forconstruction of the first model and 2 µ2-O, 2 µ3-O and 2 µ2-OСН3 ligands for the second model ofcharged clusters (for [Re4O6]10+ and [Re4O6(СH3)2]10+ respectively). The number of bonding cluster
orbitals remains the same for such structures and equals to 6. From the energy diagrams one can seethat both fragments of heteroligand complexes can be stable because of small differences between
their energy states. On the third stage we estimated the influence of terminal bonds on both charged
cluster structures [Re4O6]10+ and [Re4O6(СH3)2]10+. We input 6 terminal bonds –CH3 to every
structure (Fig.2).

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Afterwards we changed all –CH3 ligands withthe –CF3 ones. The diagrams of the energy- Re
states for these cluster structures show that-O
the fluorine-containing radical stabilizes the-CH3 or -CF3
complex structure only if it sits in the µ2OСF3 position.
Substitutions of the –OCH3 ligands by the OCF3 ligands at the terminal position does
Fig.2. Cluster structures for the third stage of
not influence apparently the order andquantum-chenical calculations
location of 6 d-d bonding orbitals, which areresponsible for the bonding in the cluster. The HOMO-LUMO separation responsible for theelectrostatic interaction is increased when H is replaced with F. The fluorine contribution to theorbitals responsible for Re-Re bonds is
negligible. This trend is observed for all structures of this model. Thus, the nature of the fluorine
influence is based on the electrostatic factors. The fourth stage of the calculations was similar to thesecond one ([Re4O6]10+ and [Re4O6(СH3)2]10+ respectively). But, importantly, we replaced 2 µ3-Оligands by the µ3-S ones. This lowers significantly the energy of bonding molecular orbirals
resulting in more stable structures in comparison with initial [Re4O6]10+ and [Re4O6(СH3)2]10+. This
raises the question whether the synthesis of the sulfur-containing analogue with µ3-S ligands isrealizable.
Experimental
Table 2. The initial molar ratios and the conditions for the To obtain heteroligand rhenium
anodic dissolution of rhenium metal with mixtures of a) alkoxides the anodic dissolution of
EtOH and PriOH and b) EtOH and CF3CH2OH
rhenium with alcohol mixtures wasapplied. The conditions of thesyntheses (I-VI) and initial molar
ratios of alcohols in the electrolytes(I-VI) are given in Tab.2. The
products of anodic dissolutions arevery sensitive even to traces ofatmospheric moisture and oxygen.
Therefore, all manipulations werecarried out in a dry box withnitrogen atmosphere. A glass
electrochemical cell with watercooling and a condenser were thefacilities for every synthesis.
To prevent the decomposition of the formed compounds a tube with a drying agent (P 2O5) wasused. The water-free EtOH, PriOH and CF3CH2OH were used as an electrolyte, a 2 cm2 platinum
plate as a cathode, and rhenium bars as an anode. Alcohols were dehydrated prior using in thesynthesis. Concentration of lithium chloride (used as background electrolyte) was 0,1 М to provide
optimal conductivity and low chlorine contamination. Before use, LiCl was annealed (180 – 200°C) in vacuum for an hour to dehydrate it. The electrochemical process was controlled bymeasuring voltage and temperature. Once the chemical reaction completed, the resulting liquid wastransferred into a glass flask and subjected to solvent vacuum evaporation to yield a final powder.
The rhenium content was determined gravimetrically as nitron perrhenate C20H16N4·HReO4 [6],carbon and hydrogen by organic microanalysis with CHN–O–RAPID (Heraeus GmbH, Germany).
X-ray diffraction patterns were obtained on a XDR 6000 powder diffractometer (Shimadzu, Japan)
with Cu Kα-radiation; IR-spectra in the range 4000-400 cm─1 were recorder on an EQUINOX 55
spectrometer (BRUKER, Germany), with the sample kept between IR-transparent KRS-5 plates in61th

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011liquefied petrolatum to prevent decomposition; Thermal analysis was performed in air on a Q–1500
D derivatograph (MOM, Hungary) up to 430°С with 5°С/min heating rate.

Results and Discussion
As one can see from the Tab.3, the results of the elemental analysis(synthesis I) on the content of Re for the heteroligand product of thereaction comes to agreement with the well-known facts. As regards the
IR-spectroscopy analysis, the peaks corresponding to 909 cm-1, 912 cm1, 910 cm-1, 913 cm-1 and 911 cm-1 for the liquid products of syntheses
I,II, III, IV,V respectively are absent in the spectrum of pure EtOH andcomplexRe, %PriOH alcohols and relate to the ν (Re–O–Re) [7,8]. Altogether, this is[2] Re4O4(OEt)1255,20
a good evidence to the fact that Table 4. An appropriate[1] Re4O6(OPri)10
52,00
heteroligand complexes were obtained. frequencies for the liquidI55,24
From Tab.4 one can see all related products of syntheses I-III.
frequencies for the liquid heteroligand alkoxides of syntheses I-III.
Consequently we can draw a conclusion that intensities and shapes of № Appropriation
frequencies, cm-1
IR-spectra are influenced by the initial molar ratios of the individual
alcohols in the electrolyte. And therefore, the ending products depend I ν О-Н = 3340
on the initial ratio of alcohols in the electrolyte. The DTA/DTG methodν С-О = 1051-1162
ν С-Н = 2885-2972
also proved that the initial ratio of the alcohols influenced on theν Re=O = 954
products of thethermal decomposition of the heteroligand alkoxides
ν Re–O (bridge) = 653because there are certain differences in the shape of the curves909
presented in Fig.3, which illustrates 3 stages of the decomposition ofν Re–O(R) = 488
complex I.
II ν О-Н = 3468
ν С-О = 1047-1162
At 85oC an endothermic effect is present. This peak corresponds to theTable 3. The data of element
analysis on the content of Re
for the first syntesis incompare with the literary
data.

DTG

T

DTA

ν С-Н = 2902-2975
ν Re=O = 1005
ν Re–O (bridge) = 816–
946
ν Re–O(R) = 477-582
III ν О-Н = 3470
ν С-О = 1093-1161
ν С-Н = 2933-2978
ν Re=O = 961-1001
ν Re–O (bridge) = 913938
ν Re–O(R) = 477

loss of 27,8% mass for theheteroligand complex I.
(While the total decrease ofweight was determined as
40,06% of the initial weightofcomplexI).
For
complexes II and III we
Fig.3. Thermogram of heating for the complex I
donot observe the same
trend. They have regular loss in mass until 400oC (total weight loss was 24,26% and 20,30% withrespect to the initial mass of complexes II and III, respectively). Also, for complexes II and III thethermal effects are less sharp as in the case of I. This can be due to the different ligands ratio in theheteroligand alkoxide structure. The thermal decompositions of Re4On(OEt)x(OPri)y in oxidative
atmosphere under 255oC is followed by the formation of rhenium oxides nanopowder. In the caseof I it is presented on Fig.4. In other cases (complexes II and III and also IV, V) one can see similar
TG

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diffraction patterns. The thermal decomposition of the fluorine-containing complexes in oxidative
atmosphere under 400oC also results in formation of rhenium oxides. In inert atmosphere (Ar) wehave another illustration for the decomposition of heteroligand complexes (DSC, Tab.5). Therefore,
the nature of atmosphere significantly influences the decomposition ways of heteroligand alkoxides
of rhenium.

Fig.4. X-ray analysis of the decomposed product of the complex I
Table 5. DSC effects for heteroligand complex I at 500OС.
complex

DSC effect, °СGeneral mass loss, %I

endothermic - 115, 412

17,45Conclusions.
By means of experimental and theoretical methods we revealed the fact that heteroligand complexesof rhenium with general formula Re4On(OEt)x(OPri)y have been obtained. The complexes arecharacterized by X-ray phase analysis, element analysis, DTG, DSC and IR-spectroscopy. The
formation of both heteroligand alkoxides complexes based on Re4O6(OPri)10 structure and one
based on Re4O4(OEt)12 is shown to be equally probable.
In the Re4O4(OEt)12 complex, part of -(OEt) ligands can be substituted by -(CH2CF3) ones. The
replacement of H atoms with F ones increases the stability of the complex only if the ligand sits inthe µ2 position.
The structure with the Re4 cluster-frame can exist, and µ3-O ligands in it are likely to be substitutedby µ3-S ligands, and the S-containing complex is expected be more stable than the O-containingone.
The thermal decomposition leads to rhenium (IV) oxides as products in different modifications(monoclinic and orthorhombic) and also produces the metastable phase Re3O10 that evidenced by
XRD.
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Anknowledgements: We thank Dr. Yuri A. Velikodniy for XRD Analyses, Elena E. Nikishina for
DTA Analyses; Dr. Sergey Savilov for DSC Analyses; Valeri V. Kravchenko for IR Spectra andVyacheslav I. Proshkin for technical support. Work was supported by RFBR (grant # 09-03-00328).
References.
1. P.A. Sheglov. Mono-, Bi- and trimetallic oxo- alkoxoderivatives of rhenium (sinthesis,
properties and application), Diss. Cand. Chem. Science. MIFCT - Moscow (2002) 141p.
2. O. A. Nikonova, K. Jansson, V. Kessler, M. Sundberg, A. I. Baranov, A. V. Shevelkov, P. A.
Shcheglov, D. V. Drobot and G. A. Seisenbaeva . Electrochemical synthesis, structuralcharacterization and decomposition of rhenium oxoethoxide, Re4O4(OEt)12. Ligand influence on the
structure and bonding in the tetranuclear planar rhenium alkoxide clusters. Inorg. Chem, 47: 12951300 (2008).
3. P.A. Sheglov, D.V. Drobot. Alkoxoderivatives of rhenium. Izv. AS, Ser. Chem., 10: 1-12
(2005).
4. Worden K.; New smart materials and constructions. Properties and applications. M:
Technosphere, 2006, p. 224.
5. N.A. Turova. Metal oxoalkoxides. Synthesis, properties and structures. Russian Chemical
Reviews. 73: 1041-1064 (2004).
6. Hillebrad V.F., Lendel H.E., Bright G.A.; A Practical Guide to Inorganic Chemical Analysis.
Chemistry. Moscow. 1966, p. 372.
7. Nakomoto K.; Infrared spectra of inorganic and organic compounds, M. «Mir», 1966, p. 412.
8. Smit A.; Applied Infrared Spectroscopy: Transl. from Eng, M.: Mir, 1982, p. 328.
T. Hartmann. Preparation, characterization and physical properties of new compounds in the system
Ln2O3 – ReO2 – ½ Re2O7 (Ln = lanthanides or yttrium). zur Erlangung des akademischen Grades
eines Dr.-Ing. genehmigte Dissertation von. Vom Fachbereich Material- und Geowissenschaften derTechnischen Universität Darmstadt - Darmstadt (2004) 72p.

The New Principle Buildingof the Presidium of Russian Academyof Sciences and the principle
interpreter of the ISTR2011
Yana Obruchnikova

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1.17.
STATUS AND PROSPECTS OF STUDIES ON THE CHEMISTRY OF
COORDINATION COMPOUNDS OF RHENIUM (V)
A.A. Aminjonov
Tajik National University. Dushanbe. azimjon51@mail.ru

As a result of the made perennial purposeful researches by us are received a series of importantresults on processes of a complex formation of rhenium (V) by sulphur or nitrogen of organic
compound ligands. In particular we managed to synthesis and identify more than 2500 new
complexes of rhenium (V). Reactions of their formation are offered. It is positioned that oncomposition of formed complexes affect both interrelations of initial reagents, and concentration
halogen acids. It was shown that in medium HX (where X - Cl, Br or F) of 6 mol/l produced oxocomplexes compositions, [ReOLX3(H2O)]; [ReOLX3]; [ReO(L-H)2X]; [ReOL2X]X2; [ReOL2X3]; [ReOL4X]X2 by
the following general reactions;
H2[ReOX5]+L+H2O=[ReOLX3(H2O)]+2HX(1)
H2[ReOX5]+L=[ReOLX3]+2HX(2)
H2[ReOX5]+2L=[ReO(L-H)2X)]+4HX(3)
H2[ReOX5]+2L=[ReOL2X]Г2+2HX(4)
H2[ReOX5]+2L=[ReOL2X3]+2HX(5)H2[ReOX5]+4L=[ReOL4X]Г2+2HX(6)
In reactions (2) and (4) ligands are bidentat, as in reaction (3) - bidentat deprotonated. In theconcentration range of 4 to 6 mol/l HX, depending on the nature of the ligand formed amonomerization
or dimerization with oxygen bridges oxo hydroxyl complexes types:[ReO(ОН)LX2(H2O)]; [ReO(ОН)L2X2];[ReO(ОН)L2]X2; [Re2O3L2X4]; [Re2O3L4]X4;[Re2O3L2(Н2О)2X4]; [Re2O2(ОН)2L2X4] in accordance with the reactions;
H2[ReOX5]+L+2H2O=[ReO(ОН)LX2(H2O)]+3HГ
(7)
H2[ReOX5]+2L+H2O=[ReO(ОН)L2X2]+3HX(8)
H2[ReOX5]+2L+H2O=[ReO(ОН)L2]X2+3HX(9)
2H2[ReOX5]+2L+H2O=[Re2O3L2X4]+6HX(10)
2H2[ReOX5]+4L+H2O=[Re2O3L4]X4+6HX(11)
2H2[ReOX5]+2L+3H2O=[Re2O3L2(Н2О)2X4] +6HX (12)2H2[ReOX5]+L+2H2O=[Re2O2(ОН)2L2X4] +6HX
(13)
In reactions (10) and (11) ligands are bidentate. In media with concentration HX below 4 mol/l
predominantly
formeddimeric
complexeswithanoxygenbridge.
We were able to develop a universal method of synthesis of complexes of rhenium (V) in
environments with low concentrations of HX whose essence lies in the fact that in order to preventhydrolytic processes in aqueous solution of ligand added to the calculated amount of H2[ReOX5] in
6 mol/l HCl and 7 mol/l HBr.
It is established that the formation of complexes of rhenium (V) with alkyl hydroxide
derivatives of thiosemicarbazide in medium HX (1-7 mol/l) occurs only when the ratio Re: L ≤ 1:1.
At high ratios Re:L is the hydrolytic cleavage of the alkyl hydroxide groups and formation of thecorresponding thiosemicarbazide complexes. Revealed that the reactions at the interface by mixing
a benzene solution of thiosemicarbazide with solutions alkyl hydroxide H2[ReOX5] in mediums HXenvironments, provides the highest yield and best purity of the complexes of rhenium (V) with thisclass of ligands.
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According to X-ray studies of the synthesized complexes of rhenium (V) are crystalline andhave either an orthorhombic or tetragonal. Based on the data magnetic chemicals, potentiometricand infrared spectroscopic studies confirmed the immutability of the oxidation state of rhenium inthe synthesized complexes. A study of thermal decomposition process of the ligands and complexes
showed a significant increase in thermal stability of the ligands in the coordination of triazoles. The
inverse association was found for the rhenium complexes two substituted thiosemicarbazide
rhenium (V). For complexes of rhenium (V) with 2-mercaptoimidazole and its derivatives were
found following the reaction with the formation of hydrate thermo gravimetric isomers.
120 СС[ReOL4 (Н2О)]X3 80 [ReOL4X]X2· H2О  [ReOL4X]Х2+ L+H2О.
00

It is proved that the Slow complexes of rhenium (V) with benzo-2,1,3-thiadiazole in 5060 C in an oven formed Re2O5. The process thermo gravimetric of monomeric hydroxo rhenium(V) proceeds with the formation of dimeric compounds by the reactions
0

160 С

 [Re2 O3 L4 X4]+ Н2О
2[ReO (НО)L2X2] 1000С [Re2 O2(ОН)2(   ТР )2X4]+2Н2О
2[ReO (НО)(ТР) X2 (Н2О)] 1100С [Re2 O3(   ТР )2X4] +Н2О.
[Re2 O2(ОН)2(   ТР )2X4] 210
For thiosemicarbazide methylenesemicarbazide complexes of rhenium (V) proposed the following
reaction of thermolysis0С [ReOL(SCN)X2]+NH3+НX+HCN.
[ReOL2X]X2 170
Depending on the nature of the coordinated ligand onset temperature of decomposition ofcomplexes of rhenium (V) changes in the following order:
0[ReO(FTSC) 2 Br] ≈ [ReO(FTSC) 2 Cl] ≈[ReO(GDTC) 2 Br] >
478К

476К

473К

[ReO(GDTC) 2 Cl]>[ReO(Tthiol)Cl 2 H2 O(OH)]> [ReO(Tthiol)Br 2 H2 O(OH)]>
463К

443К

435К

[ReO(Tthiol) 2 Cl 2 (OH)]>[ReO(Tthiol) 2 Br 2 (OH)]> [Re 2 O3 (TSC) 2 Cl 4 ]>
428К

418К

405К

[Re2 O3 (TSC) 2 Br4 ]>[Re 2 O3 (TSC) 4 ]Cl 4 > [Re 2 O3 (TSC) 4 ]Br 4 >
396К

383К

371К

Using a flow-type reactor, kinetics of the formation of thiocyanate complexes of rhenium(V) with thiosemicarbazide. Held kinetic analysis showed that the range of degrees of conversion of
0,005 ≤ α ≤ 0,58 studied process is best described by the equation k=[1-(1-α)], and at higher valuesof α-diffusion equation Yandera. The results of kinetic analysis of the formation of thiocyanate
complex of rhenium (V) c TSC are presented in Table I.
Table I. Kinetic parameters of the process of thermal decomposition oxohalogen- thiosemicarbazide
complexes of rhenium (V)

№
1.
2.
3.
4.

The compositionof compounds[Re2O3(TSC)2Cl4][Re2O3(TSC)2Br4][Re2O3(TSC)4]Cl4[Re2O3(TSC)4]Br4

Mechanism1[1-(1-α) 3 ]-"-"-"-

Interval α,%0,7÷52,3
0,5÷58,82,7÷39,2
3,9÷36,3

Stand.
deviat.
120,91
1,01
0,62
0,58

E,
kJ/mole
120,1
118,8
113,2
99,6

А
1,65∙1013
1,15∙10 1 3
8,15∙10 1 07,45∙10 1 066

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

Presented in Table I show that compounds with a ratio of Re: TSC = 1:1, are more stable
than the complexes of 1:2. In addition, at the same ratio of Re: TSC are more stable chloride
complexes. The data on the thermal stability oxohalogen complexes of rhenium (V) withthiosemicarbazide correlate with the results of IR spectroscopic data on the magnitude of the shearbands (C = S).

The kinetics of interaction with the complexes of NH3(g) [ReO(FTSC)2X], where X - F-, Cl-,
Br , I , CH3COO-, NO- has shown that with increasing temperature generally slows down the speedof the process and reduces the number of moles of accession ammonia. In the first stage of thereaction is displaced by ammonia entering into the inner sphere complexes by the scheme:[ReO(FTSC)2X] +NH3 → [ReO(FTSC)2NH3]X
Mathematical processing of experimental data using kinetic equations, based on certain physicalmodels, showed that the interaction of chloride, bromide and iodide complex with the NH3(g) by the--equation k  =[- ln(1   ) ] 4 and fluoride, nitrate and acetate, respectively, k  =[ 1  (1   ) ] 3
calculated rate constants are Table. 2.
1

1

Table 2. Rate constants of the interaction of complexes of general composition [ReO(FTSC)2X] with gaseousammonia in the range 293-323K

№
1.
2.
3.
4.
5.
6

Composition
complexes[ReO(FTSC)2J][ReO(FTSC)2Br][ReO(FTSC)2Cl][ReO(FTSC)2CH3COO][ReO(FTSC)2NO3][ReO(FTSC)2F](k, sеc-1). 10-3
293К
28,0
11,0
4,2
2,7
2,3
2,2

303К
10,0
7,7
2,7
2,1
1,7
1,8

113К
5,8
2,4
2,0
1,5
1,0
1,5

323К
3,3
1,1
1,2
0,92
0,55
1,0

From the data of Table 2 shows that k values decrease with increasing temperature. A similar
dependence of k on temperature was observed Pavlyuchenko MM and Lazerko GA in the study ofthe interaction of NH3(g) with the chlorides of cobalt and zinc. The rate of interaction with thecomplexes of NH3(g) [ReO(FTSC)2X] depends on the nature atsidoligandov lability which at 293K
changes in the following order:
I- > Вr- > Cl - > CH 3 COO- ≥ NO 3 ≈ FOn the basis of thermo gravimetric studies show that the decomposition temperature of theonset of intense complexes of rhenium (V) depends on the nature of the alkyl radical, which is part
thioamino ligands. On this basis suggest appropriate ranks.
Found that the thermal decomposition of uncoordinated sulfur compounds azole series
depends on the nature of the alkyl radical and its provisions. We propose the following series oftemperature changes in the beginning of intensive thermal decomposition of the ligands: 1,2,4triazole (105 ° C) <4-methyl-1 ,2,4-triazoltiol-5 (200 ° C) < (210 ° C) <1,2,4-triazoltiol-5 (220 ° C)
<3-methyl-1 ,2,4-triazoltiol-5 (230 ° C). Studies conducted on the process of thermal decompositionof complexes of rhenium (V) 3-Et-4-Met-l ,2,4-Thiol and 3,4-DiMet-l ,2,4-Thiol, show that the
majority of the synthesized compounds contain water of crystallization and the first stage of thermal
decomposition of these complexes is related to their thermo dehydration. For the monomericcomplexes containing water of crystallization, together with and coordinated water, the second
stage of thermal decomposition removes the molecules of coordinated water with subsequent
dimerization of the reaction:t
2[ReO(OH)L(H 2O)Cl2] [Re2O3(  -L)2Cl4]+3H2O
0

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The third stage of thermal decomposition is connected with partial decomposition of themolecules of 3-Et-4-Met-l,2,4-Thiol and 3,4-DiMet-l ,2,4-Thiol and the formation of newcompounds containing the deprotonated molecule of thiourea.
t[Re2O3(  -L)2Cl4] [Re2O3(N2SCH3)2Cl4]+2C2H5CN+C2H20

Investigation of thermal properties of complexes of rhenium (V) with Ethio and l-Et-2MI
showed that increasing the number of coordinated molecules Ethio and l-Et-2MI leads to a slightdecrease in temperature of the beginning of the process thermo dehydration, but does not affect thetemperature of the end of this process and the peak temperature endo effect. This increases thetemperature of the onset of decomposition of complexes. It is established that, irrespective of thenature of halide ions with the number of coordinated molecules Ethio, l-Et-2MI increases thenumber of molecules of water in the complexes. It is shown that the replacement of chloride
complexes demerization ions to bromide to 300 ° C to slow the process of thermolysis, while above
this temperature there is an opposite effect. This means that for the chloride and bromide complexesof rhenium (V) depending on Δm = f (T) there is a point of intersection, which varies from theeffect of halide ions on the process of thermolysis of complexes of rhenium (V). A similar point ofintersection of the curve and there is Δm = f (T) for two-and tetra complexes, from which changes
the effect of the coordinated molecules Ethio and l-Et-2MI the process of thermolysis of complexesof rhenium (V).
Investigated the acidic properties of some synthesized complexes and determined theirbasicity. Calculated acid dissociation constants of the successive test compounds.
Prior to the beginning of our research processes of mutual substitution of ligands in complexesof rhenium (V) remained virtually unstudied. We carried out studies on the substitution of
coordinated ligands in the complexes of rhenium (V) other ligands, particularly thiocyanate ligand,molecules of ammonia, dimethylformamide, pyridine, acetonitrile, dimethyl sulfoxide, quinoline,
triphenylphosphine.
On the basis of experimental studies on the mutual substitution of ligands in complexes ofrhenium (V) made some conclusions about the spatial arrangement of the ligands in the octahedral
plane. In particular, it was determined that the action of triphenylphosphine in 2merkaptobenzimidazolny complex rhenium (V) of [ReOL(H2O)Br3]H2O in the medium of acetone
formed complex of [ReOL(PPh3)Br3]2H2O from the equation[ReOL(H2O)Br3]H2O+PPh3= [ReOL(PPh3)Br3]2H2O.
Even with an excess of triphenylphosphine, compounds with a large number of molecules
coordinated PPh3 is formed. For the original complex structure [ReOL(H2O)Br3], there are four
possible spatial arrangement of the ligands:
Br

O
Br

L

Br
L
(I)

Br

L

Re

Re
H2O

O

H2O
(II)

Br

L

Br

H2O
Br
(III)

O

Br

Re

Re
Br

Br

O

Br

H2O
Br
(IV)

If the source of the complex [ReOL(H2O)Br]∙H2O would have the configuration (I) or (III),after replacement of water molecules on triphenylphosphine, due to the large trans influence of thelatter was replaced by bromide ion, which is in trans position to triphenylphosphine, that is, would
form a complex of trans-[ReOL(PPh3)2Br2]+. Configuration (II) is unlikely, because in the IR
spectrum of the original complex [ReOL(H2O)Br3]H2O maintained an intense band corresponding68th

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

to stretching vibrations rhenium (Re = O) group. If in a trance - the position of the oxygen renilnoy
was a water molecule, the intensity of this band would have decreased to low. Also note that theliterature no data on the complexes of rhenium (V), in which triphenylphosphine would be in transposition relative to oxygen.
In the case of configuration (IV) molecule of triphenylphosphine, replacing a water molecule,stands in the trans position to the molecule 2-merkaptobenzimidazola (L) in the equatorial plane.
The second molecule of triphenylphosphine can not supplant any molecule of 2-MBI, or bromideions in cis-position, due to steric reasons. According to the literature in the triphenylphosphinecomplexes of rhenium (V) forms only the trans isomers. As a result of these factors, the process
stops at the formation of [ReOL(PPh3)Br3]2H2O. Thus, the study of the interaction of
triphenylphosphine with a complex composition [ReOL(H2O)Br3]H2O yielded evidence that thiscomplex has a configuration of (IV).
Based on data for the study of processes of mutual substitution of ligands in complexes ofrhenium (V) was proposed following a number of mutual substitution of the ligands:
L ≈ P(Ph)3>SCN->NH3>Cl-, Br->S>H2O, where L - tioamidnoe connection and S-DMF,
DMSO, Py, Hin, CH3CN.
Investigating the interaction of ammonia with the amide and complexes thioamides rhenium(V), set up three types of reactions. The first type includes reactions which take place only with thedisplacement of halide ions from the inner sphere complexes. The second type of reactions include
dimerization reaction of monomeric complexes with the replacement of halide ligands. The third
type of reactions are reactions that result in coordinated thiocyanate ions are converted into
tioamidinovuyu group, although the molecules of ammonia thiocyanate ions from the inner spherecomplexes are not displaced.
It is established that the reaction of ammonia complexes of rhenium (V) with inorganic andorganic acids occur in different ways and depend on many factors, including the nature of the acidand its strength.
By using the developed electrodes reversible ligand (20) based on the sulfur-containing
organic compounds and their oxidized forms, the values of step formation constants of complexesof rhenium (V) in media with different concentrations of HCl and HBr in the temperature range
273-338K. A method for determining the formation constants of complexes of rhenium (V) by thepotentiometric method in environments with low concentrations of HHal. The regularities of theinfluence of the ionic environment, temperature and nature of the ligand on tioamidnogo stability of
the complexes of rhenium (V). The regularities in the change of E0, depending on the nature
tioamidnogo connection. We propose some general guidelines on the use of reversible redox
systems for the study of complex formation.
As a result of targeted research identified several aspects of the practical use of complexes ofrhenium (V) with amide and tioamidnymi ligands. In particular, we show that tioamidnye
compounds and complexes of rhenium (V) with greatly increased resistance to radiation and reduce
the electrified polymer materials. The features of rhenium complexes more stable effect (V). In thiscase revealed an unusual stabilizing effect of the complexes in contrast to the uncoordinatedligands. The regularities of the influence of the number of coordinated ligands and the structure of
the complexes on the radiation resistance of polymers. It is shown that some complexes of rhenium(V) increases the radiation resistance of polymers, both in terms of photo-aging, and in photomechanics.
Study of the biological action of complexes of rhenium (V) and the ligand is shown that thecoordination of ligands to rhenium (V) leads to a significant reduction in their toxicity. The effect oforganic and inorganic ligands on the toxicity of the complexes of rhenium (V).
The values of LD50 values found for some of the ligands and complex compounds of rhenium(V) are given in Table. 3. From Table. Figure 3 shows that the complex compounds of rhenium (V)with 1-methyl-2-merkaptoimidazolom, thiosemicarbazide, 4-phenylthiosemicarbazide and 1formyl-3-thiosemicarbazide are low-toxic compounds. It should be noted that complexes with 1,2,4triazole and 4-amino-1 ,2,4-triazole are practically non-toxic compounds.
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Table 3. LD50 values of complex compounds of rhenium (V)

№
п/п

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.

Complex compounds
rhenium (V)L-1-methyl-2-merkaptoimidazol[ReOL4Br]Br2∙2H2O[ReOL4Cl]Cl2∙2H2O[ReOL2Br3] ∙2H2O[ReOL2Сl3] ∙2H2O
L - 2 merkaptoimidazol[ReOL4Cl]Cl2∙2H2O
L - thiosemicarbazide[ReOL2Cl]Cl2∙H2O[ReOL2Br]Br2∙H2O[Re2O3L4]Br4[ReOLBr3]
L - 4-phenyl-3-thiosemicarbazide[ReOL2Br2]∙2H2O[ReOL2Cl3]∙2H2O
L-1-formyl-3-thiosemicarbazide[ReOL2NH3]Cl[ReOL2Cl]
L - 1,2,4-triazole[ReO(ОН)]Cl2∙H2O[ReO(ОН)]Br2∙H2O
L - 4-amino-1 ,2,4-triazole[Re2O3L2Cl4(H2O)2][Re2O3L2Br4(H2O)2]

Solubility
in water

LD50
Inside peritoneal
introduction

Oral
introduction

soluble-"-"-"-

750±39900±40850±32
700
465

-"-

105±10,4550±19,3-"-"-"insoluble
insoluble

140±4,61383±38433±51,3-"-

320±20290±20-"-"-183
650±40260±30

-"-"-

>4000
>4500

-"-"-

~2000
~3000

It must be emphasized the fact a significant reduction in toxicity with thiosemicarbazide
coordination of its molecules with rhenium (V). Thus, if the TSC for free intraperitoneal LD 50 isequal to 14 ± 2,15, ie is a toxic compound, the complex composition [ReOLBr3] is equal to theLD50 433±51,3. For thiosemicarbazide complexes observed increase in the degree of toxicity withincreasing number of coordinated organic ligand molecules, and for the 1-methyl-2merkaptoimidazolnyh complexes observed an inverse relationship. In analyzing the impact ofinclusion in the composition of the complexes of halide ions established that the bromide
compounds are less toxic than similar chloride compounds. Based on these studies we can conclude
that the introduction of formyl group of the thiosemicarbazide leads to a decrease in toxicity
rhenium complex of more than two times. Due to poor solubility of 4-feniltiosemikarbazidnyh
complexes, their toxicity is investigated only by the oral route of administration. These compounds
were administered in the form of 1-2% water-glycerol solutions with a ratio of water: glycerol =10:1. 1,2,4-triazole and 4-amino-1,2,4-triazole complexes when administered orally in the form ofwater-glycerol solutions were practically non-toxic compounds.
Total Calc. 3 change the toxicity of complexes of rhenium (V) with amide ligands andtioamidnymi can be arranged in the following order:[ReO(OH)(TP)Br2(H2O)]≥[ReO(OH)(TP)Cl2(H2O)]>>[ReO(OH)(4-ATF)Br2(H2O)]>[ReO(OH)(4-ATF)Cl2(H2O)]>>[ReO(1-Met-2-M,)Br]Br2∙2H2O>[ReO(1-Met-2-MI)4Cl]Cl2∙2H2O>> [ReO(2-MI)4Cl]Cl2∙2H2O.
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Among the complexes synthesized by us were found compounds with rengenokontrastnymi
properties, seizure and antivitamin activity, dose-dependent effect antiyazvennym, radioprotective
and antithyroid action, as well as the substance showing an anabolic effect.
Some complex compounds of rhenium (V) showed resistance at temperatures of curing thematrix, giving the composite materials set the necessary properties, samozatuhaemost, heat
resistance, corrosion-and high dielectric properties. It was possible to show the principal possibility
to achieve a monolithic matrix, reducing the time to cure, the implementation of the single-stage
curing of thermosetting binders of different chemical nature, improving the number of properties
and imparting new properties of composite materials. In this case elimination makrodefektnosti
matrix is achieved by optimal amounts of the complex and the choice of the new regime (selectedaccording to criteria monolithic matrix) curing the composite material using a nondestructive
method of electro control. In particular, the processes of curing of thermosetting binders LBS-4,
ENFB, BFOS 0.01% modified complexes of rhenium (V) compared to the known modes ofaccelerated respectively 7.9, 9.4; 9.6 times. In this modified polymers are homogeneous and haveacquired a new quality - samozatuhaemost. By introducing a complex of rhenium (V) in theepoksiuretanovogo polymer consisting of heterogeneous oligomers, obtained the matrix of new
generations capable of forming interpenetrating structures, where the defective areas of hardening
due to the formation of network polymers kation different chemical nature. In this direction,
developed the scientific foundations of technology for the processing of polymer composite
materials with desired properties.
Interesting data on the effect of some synthesized complexes on the germination and vigor ofseeds of some crops.
Perfection has no limits and therefore chemistry of coordination compounds of rhenium (V)should be developed and far and wide, attracting new more advanced methods of research,equipment, and theoretical views. In our opinion, in the short term is expedient to continue studies
in the following areas of chemistry of coordination compounds of rhenium (V):-using new classes of ligands targeted synthesis of complexes of rhenium (V);-study of the processes of mutual substitution of ligands in complexes of rhenium (V);-research the process of chelation of rhenium (V) in HCl solutions at constant concentration [H+]and [Cl-]-ion at different temperatures;
ΔH-determination of the processes of formation of complexes of rhenium (V) by the calorimetricmethod;-study of the processes of interaction of donor molecules as NO and CO complexes with rhenium(V);-determination of kinetic parameters of the interaction of ammonia with complexes of rhenium (V)depending on the nature of coordinated organic and inorganic ligands;-investigation of the complexation of rhenium (V) using different electrical methods;-search the complexes of rhenium (V) compounds exhibit high biological activity in order to create
new and effective drugs;-study towards obtaining new nano composites with complexes of rhenium (V) ions and othermetals;-works on the comparison of stability, physicochemical and other properties of the complexes ofrhenium (V) with ions of other metals;-developed oxidation-reduction electrode systems based on rhenium compounds in different
oxidation;-establishment of the laws on the influence of various factors on the electrified and otherelectrical properties, as well as on the radiation resistance of polymer and polymer composites
modified complexes of rhenium (V).

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I.G. Tananaev, A.A. Aminjonov, K.E. German

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1.P1.
EFFECT OF THE RHENIUM(V) COMPLEX OF 3,4-DIMETHYL-1,2,4TRIAZOL-5-THIOL ON THE CELLULOSE DIACETATE LIGHT
FASTNESS
N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjоnov

Tajik National University. Dushanbe. azimjon51@mail.ru

The effect of various concentrations of 3,4-dimethyl-1,2,4-triazol-5-thiol and the complex
compound [ReOL2(OH)Cl2] (L-3,4-dimethyl-1,2,4-triazol-5-thiol) light fastness diacetate cellulose(DAS) has been studied. As an example, the table shows the experimental data depending on thetensile strength of the DAS complex concentration and time of UV irradiation.
Table 1. The dependence of the tensile strength of DAS on the concentration of complex composition[ReOL2(OH)Cl2], where L-3,4-dimethyl-1,2,4-triazol-5-thiol and UV irradiation (λ = 254nm, I =- 0,040
Kal/cm2.min)

The
concentration of
additives,%
0
0,01
0,05
1
3
5

Exposure time, h
0

2

5

10

15

20

25

10,6
10,2
9,5
9,8
10,1
10,5

7,2
9,6
9,3
10,1
9,2
9,4

6,0
10,2
9,9
9,8
8,4
8,3

4,7
9,4
10,8
9,2
6,8
5,9

3,0
8,3
10,0
6,0
5,1
4,8

2,6
8,0
9,3
5,2
4,6
4,1

1,1
7,6
7,0
4,0
3,0
2,9

The table shows that the introduction various amounts of the complex compound[ReOL2(OH)Cl2] to the DAS has little effect on its initial tensile strength. However, there is a
general tendency to the coefficient increasing of light fastness DAS at the introduction into it ofvarious amounts of complex composition [ReOL2(OH)Cl2]. In addition, the curve of the tensile
trength of the UV irradiation time for the modified films at additives concentrations equal to 0.05%
it is the maximum. It means, the tensile strength of modified film exceeds its initial tensile strength.
Studies have shown that the coordination compounds of rhenium (V) shows great lightstabilizing activity against DAS compared to uncoordinated ligand.

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1.P2.
OCTAHEDRAL RHENIUM(III) CHALCOCYANOHYDROXO
CLUSTER COMPLEXES
A.V. Ermolaev, A.I. Smolentsev, K.A. Brylev, V.E. Fedorov, Y.V. Mironov
Nikolaev Institute of Inorganic Chemistry, Siberian Branch of Russian Academy of Sciences, 3 Acad. Lavrentiev
Prosp., 630090 Novosibirsk, Russia (e-mail: erandrey@yandex.ru)

In recent years the compounds containing hexarhenium cluster anions [{Re6(μ3-Q)8}L6]n– (Q =S, Se; L = Cl, Br, I) have been intensively investigated. The rapid development of rhenium cluster
chemistry has led to the discovery of substitution reactions of L on other ligands, including organic.
Polymeric compound Re6Q8Br2 prepared from the reaction of Re with the appropriate stoichiometryof Q and Br2 at 800 С in sealed quartz ampoule. Octahedral rhenium(III) cluster
chalcohydroxocomplexes have been prepared from the reaction of polymeric chalcobromide
Re6Q8Br2 with molten KOH at 220-250 С in air.
In this work we present our data in the synthesis and structural study of compounds with
[Re6Q8(CN)n(OH)6-n]4– (n = 2, 4) cluster anions containing two type terminal ligands – OH– andCN–. Such clusters are interesting because CN - ligands can form bridging bonds through thenitrogen atom and OH - ligands can be easily replaced by both inorganic ligands and organic
molecules and ions. For these complexes we have proposed a simple and convenient method basedon the interaction of K4[Re6Q8(OH)6].8H2O with KCN in aqueous solution. It has been found thatwhen Q = S the cluster anion [Re6S8(CN)2(OH)4]4- formed; however, if Q = Se the composition[Re6Se8(CN)4(OH)2]4- was found.
The structure of [Cu(NH3)4]2[Re6S8(CN)2(OH)4]2H2O cluster complex was determined bysingle-crystal X-ray diffraction. In addition, the presence of four OH– groups in the cluster anion
was confirmed by the fact that as a result of its interaction with molten 3,5-dimethylpyrazole themolecular complex [Re6S8(CN)2(3,5-Me2PzH)4]·2H2O formed.
The structure of [Re6Se8(CN)4(OH)2]4– cluster anion was confirmed by single-crystal X-ray
diffraction for complex trans-[Ni(NH3)5]2[Re6Se8(CN)4(OH)2]·6H2O obtained by reaction ofCs4[Re6Se8(CN)4(OH)2].2H2O with NiCl2·6H2O in an ammonia solution.
In addition, the compounds were characterized by a set of physical-chemical methods.

This research was supported by Russian Foundation for Basic Research (Grant 11-03-00157) andby GC № 02.740.11.0628 of FFP “SSESIR 2009-2013”

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1.P3.
TECHNETIUM AND RHENIUM ORTHOPHOSPHATES WITH
KOSNARITE-TYPE STRUCTURE

M.V. Sukhanov, V.I. Pet'kov

Lobachevsky State University of Nizhni Novgorod (pr. Gagarina 23, Nizhni Novgorod, Russian Federation)

Keywords: technetium (IV) and rhenium (IV) orthophosphates, synthesis, crystal structure,kosnarite
Abstract
This work represents an attempt to incorporate chemically technetium (IV) and rhenium (IV)in the cationic crystallographic positions of the kosnarite-type structure obtaining AM2(PO4)3 (A =Li, Na, K, Cs; M = Tc, Re) compounds. The phosphates were prepared by the combined method
using of solids TcO2 or K2TcCl6, NH4ReO4, ACl and phosphoric acid solution. Drying mixtures andtheir thermal treating in sealed glass ampoules allowed us to obtain the crystalline phosphates
ATc2(PO4)3, ARe2(PO4)3 (A = Na, K) with the kosnarite-type structure determined by the Rietveld
refinement. Compounds were characterized using XRD, DSC, IR-spectroscopy and microprobe
analysis.
Introduction
The major problem of inorganic technetium chemistry is its fixation from commercial nuclear
wastes in ceramic matrices and also a search of useful properties and possible areas of theirapplication. NZP-ceramics with the kosnarite mineral KZr2(PO4)3 (sp. gr. R 3 c, Z = 6) structure are
well-known matrices for the toxic component immobilization of different waste forms including
highly radioactive waste and have some useful properties e.g. catalytic [1, 2]. Up to now, ourknowledge about of rhenium phosphates are limited by several works [3–5] devoted rhenium
pyrophosphate ReP2O7 and there are no literature data about solid technetium phosphates. In thecurrent work we investigated the possibility of Tc(IV) and Re(IV) incorporation in the phosphates
AM2(PO4)3 (A = Li, Na, K, Cs; M = Tc, Re) with the kosnarite-type structure. This research may
provide a more detailed understanding for inorganic chemistry of technetium and rhenium.
Experimental

Under rhenium phosphate synthesis the crystalline salts NH4ReO4, AСl and concentrated
phosphoric acid solution were used. Technetium phosphates were made of TcO2 or K2TcCl6
exposed to preliminary hydrolysis by concentrated ammonia solution (K2TcCl6 + 4NH4OH
hydrolisis TcO2∙2H2O + 2KCl + 4NH4Cl). In the last case there was fourfold KCl excess in thedried residuum in comparison with the quantity needed for KTc2(PO4)3 synthesis. The synthesis
scheme of AM2(PO4)3 phosphates is shown on the figure 1.
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Powder XRD patterns were collected at room temperature with a XRD-6000 type diffractometer(Shimadzu) using CuK radiation. The structures were refined with the RIETAN-97 software
package. The A:M:P molar ratio and homogeneity of the single phases were determined with a
Camebax microprobe. IR spectra were obtained by means of a FSM–1201 spectrophotometer in thefrequency range 1400−400 cm-1. Synchronous differential thermal and gravimetric analysis was
carried out on a LABSYS TG−DTG/DSC thermal analyzer (Setaram) in an argon atmosphere
within 25−1200°С at a heating rate of 10°С·min-1.
2NH4ReO4(s) + ACl(s) + 3H3PO4(soln)
2TcO2(s) + NaCl(s) + 3H3PO4(soln)
2TcO2∙2H2O(s) + 4KCl(s) + 3H3PO4(soln)

drying at 400°C 2
thermal treating in→ hours on air and → sealed glass ampoules atregrinding
500°С 48 h

Fig. 1. Scheme of synthesis of the phosphates (s – solid, soln – solution).

Results and Discussion

224

042
102●

331

021
112

5

004

022

113

100●

002

b

222
002●

a

111

Heat flow, mW

10

980

738

↑ Exo
15

101●

Phosphate synthesis results showed that reaction mixtures drying of short duration in the air at
400°С promoted initial reaction passing of salt decomposition and their interaction with phosphoricacid, allowed us to remove volatile compounds (H2O, HCl, NH3) and did not lead to distinct
rhenium and technetium oxidation that greatly simplified the synthesis. Endothermic effects on
DTA curve of reaction mixture for NaRe2(PO4)3 synthesis refer to the evaporation of water,hydrochloric acid, the decomposition of ammonia perrhenate and its interaction with phosphoricacid correspondingly (Fig. 2a). The mixtures dried at 400°С accordion to XRD data were
amorphous. Heating in the air could not be used at all synthesis stages. In the air at 500°С thethermal treatment of the mixtures dried at 400°С resulted in ReP2O7 formation. Long being of thesemixtures in sealed glass ampoules at 500°С allowed us to obtain crystalline products in all thesystems. NaRe2(PO4)3 and KRe2(PO4)3 samples were phase-pure kosnarite-type phosphates.
Crystalline TcO2 using did not permit us to receive the pure phosphate NaTc2(PO4)3. The sample
contained two phases: mostly kosnarite-type phase and 22 wt.% TcP2O7. The sample KTc2(PO4)3synthesized from the dry hydrolysis residuum of K2TcCl6 was also double phase and contained
KCl. After KCl excess washing with water and the product recrystallization in the sealed glass
ampoules at 500°С, the pure KTc2(PO4)3 sample was prepared. In ARe2(PO4)3 (A = Li, Cs) systems
kosnarite-type phosphate forming were not observed. DTA of NaRe2(PO4)3 obtained at 500°С
allowed us to reveal the area of intensive sample crystallization (exothermal effect at 738°С) andthe temperature of its decomposition beginning (endothermic effect at 980°С) (Fig. 2b). The
disproportion product of NaRe2(PO4)3 according to XRD were ReP2O7 and metal Re (Fig. 3).

0
0

400

800

1200

T, °C
Fig. 2. DTA curves of reaction mixture for
NaRe2(PO4)3 synthesis (a) andNaRe2(PO4)3 obtained at 500°С (b).

10352θ, deg60

Fig. 3. XRD-pattern of disproportion product ofNaRe2(PO4)3: ReP2O7 (sp. gr. P a 3) andRe (●) (sp. gr. P63/c).

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100 μmNa0.95(4)Tc2.02(7)P3.08(5)O24
Tc0.98(5)P2.11(6)O24

50 μm
K1.09(4)Tc1.98(5)P2.92(5)O24

100 μm50 μm

Na1.02(3)Re2.07(5)P2.92(5)O24 K1.07(3)Re1.94(4)P2.96(4)O24

Fig. 4. Microstructure and chemical composition of the sample phosphates.

The results of the electron microprobe analysis confirmed that the monophase phosphate samples
were crystalline (crystallite size ~10 μm), homogenous and their composition corresponded to thetheoretical one to within the inaccuracy of the method (Fig. 4).
The crystal structures of sodium and potassium contained phosphates were determined by the
Rietveld refinement (Fig. 5). Details of X-ray diffraction experiment, unit cell parameters, andstructure refinement details are presented in Table. In the three-dimensional structures[(Tc,Re)2(PO4)3]− units consisting of two ReO6- or TcO6-octahedra and three PO4-tetrahedra arelinked to form the ribbons parallel to the c axis. These ribbons are linked together by PO4tetrahedra. The framework cavities are populated by Na+ and K+ ions. The calculated bond lengths
between the atoms are typical of rhenium and technetium compounds: Tc–O 1.959(3)–2.001(5) Å,
Re–O 2.000(7)–2.032(7) Å, P–O 1.44(1)–1.62(1) Å, Na–O 2.50(1)–2.53(1) Å, K–O 2.63(1)–2.73(1) Å. The framework of KM2(PO4)3 phosphates with large kation K+ is considerably deformedin comparison with Na-containing phosphates (Fig. 4). Tc4+ and Re4+ ions are relatively small (0.58
and
0.63
Å
correspondingly)
and
not
able
to
form
1

2

3
4
Fig. 4. Experimental (solid line) and calculated (asterisks) X-ray diffraction pattern of the synthesized
samples: NaTc2(PO4)3 (1b), TcP2O7 (1a), NaRe2(PO4)3 (2), KTc2(PO4)3 (3), KTc2(PO4)3 (4). Crystal
structures and the positions of the reflections in the calculated XRD pattern are shown in the figures.

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Table. Details of the X-Ray diffraction experiment and results of crystal structure refinement of technetiumand rhenium-containing phosphates
Characteristic
NaTc2(PO4)3
TcP2O7
KTc2(PO4)3
NaRe2(PO4)3
KRe2(PO4)3

301

P a 3, 4
7.8643(2)486.39(3)3.726(1)R 3 c, 6
R 3 c, 6
8.2917(2)8.4541(1)23.2255(5)22.3320(3)1382.87(5)1382.25(3)3.761(1)4.904(1)10.00 – 110.00
197
195

R 3 c, 68.3155(2)23.3867(5)1400.48(5)4.954(1)
199

55

34

36

34

6.92
5.13

6.45
4.02

4.33
3.73

6.57
6.14

1300

569

659
914

b

987

1043

900

639

a

1068

a framework containing large Cs+ ions as with Ti4+ (0.61 Å).
Also there are ATi2(PO4)3 (A = Li, Na, K, Rb) phosphates
having the kosnarite-type structure, CsTi2(PO4)3 having the
kosnarite-type structure cannot be synthesized.
The IR spectroscopic data of the synthesized phosphates arein agreement with the X-ray diffraction data and suggest thatthese compounds belong to the orthophosphate class. The IR
spectra of technetium- and rhenium-containing phosphates
are similar to those of double phosphate of alkali metal andzirconium or titanium. In the IR spectra, the adsorption bands
observed at frequencies of 987–1226 cm-1 are assigned to theν3 stretching vibrations of the P–O bonds in the PO4tetrahedra, the adsorption band at a frequency of 914 cm-1 isattributed to the ν1 stretching vibrations, and the adsorption
bands in the range 547–659 cm-1 correspond to the ν4
bending vibrations.

547

R 3 c, 6
8.4091(1)22.2602(3)1363.18(4)3.696(1)

1226
1144

Space group, Z
a, Å
c, Å
V, Å3
ρXRD, g/cm3
2 range, deg
Number of reflection
Number of parametersrefinement
Rwp, %S

 , cm-1

500 c

Fig. 5. IR-spectra of samples:
Conclusions
Thus, the crystalline phosphates ATc2(PO4)3, ARe2(PO4)3 (A NaTc2(PO4)3 (a), KTc2(PO4)3 (b),= Na, K) with the kosnarite-type structure were synthesized NaRe2(PO4)3 (c), KRe2(PO4)d3 (d).
by the combined method. Tc4+ and Re4+ were shown to enteroctahedral framework positions in the kosnarite-type structure.

Acknowledgments: The work was supported by the Russian Foundation for Basic Research, projectno. 11-03-00032.
References
1. V.I. Pet'kov, M.V. Sukhanov, M.M. Ermilova, N.V. Orekhova, G.F. Tereshchenko. Russian J.
Applied Chem. 83(10): 1731−1741 (2010).
2. V.A. Sadykov, S.N. Pavlova, G.V. Zabolotnaya et al. Kinet. Katal. 42(3): 432−441 (2001).
3. E. Banks, R. Sacks. Mat. Res. Bull., 17(8): 1053–1055 (1982).
4. K. Popa, V. Brandel, A. Cecal. Rev. Roumaine de Chim. 46(5): 509–515 (2001).
5. V.V. Lisnyak, N.V. Stus, D.A. Stratiichuk, N.M. Belyavina, V.Ya. Markiv. Phosphorus, Sulfur,
and Silicon. 183: 2248–2255 (2008).

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1.P4.
DEPTH DEUTERIUM AND HYDROGEN CONCENTRATIONS IN SET OF
Re-Mo FOILS MEASURED AFTER ACTION OF PULSE HIGHTEMPERATURE DEUTERIUM PLASMA
A.Yu. Didyk1, V.S. Kulikauskas2, R. Wiśniewski3 , A.N. Majorov4
1

Joint Institute for Nuclear Research, Flerov Laboratory of Nuclear Reactions,
Dubna, Moscow Region, Russian Federation
2
Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University,
Moscow, Russian Federation
3
National Centre for Nuclear Research, 05-400 Otwock/Świerk, Poland
4
Lebedev Physical Institute of Russian Academy of Sciences, Moscow, Russian Federation

Keywords: plasma-focus set-up, high temperature plasma, elastic recoil detection, shock waves,
depth concentration, diffusion parameters, rhenium-molybdenum alloy, transport of deuterium,hydrogen
Abstract
The depth distributions of deuterium and hydrogen atom concentrations in sets of Re-Mo alloy foils
after action of high temperature deuterium plasma bombardment using “Plasma Focus” set-up (PF4) were measured using elastic recoil detection method. It is established that the implanted
deuterium and existing hydrogen atoms are transferred to a large depths in the set of foils, much
deeper than the projected ranges of deuterium ions from the plasma with the maximum it’svelocities of about 108 cm/s. The increasing of depth hydrogen concentrations in the set of Re-Mo
foils was determined. The coloring of three first Re-Mo foil surfaces nearer to PF-4 set-up are
observed too. The obtained results can be explained by large power density of pulse deuterium
plasma arising of shock waves and large mechanical tension which influence on the transport andredistributionof
deuteriumionsandhydrogen
atoms
at
large
depths.
1. Introduction
In recent years, due to significant big advances in laser technology and the creation of powerfulpulse lasers in the pico-(10-12 s) and femtosecond (10-15 s), second life has received a relatively new
area of science - the physics of high energy density [1, 2]. This trend has evolved in the direction of
studying the action of short pulses with condensed matter, i.e., processes such as laser sputtering,
ablation, intermixing of impurities, the creation of new phases and influence of the of powerfulshock waves [3, 4]. In addition, it was formed another important area of research on effects of highpower laser pulses for developing of a laser-controlled nuclear fusion. As it is known, theaccumulation of plasma components (deuterium and tritium) and the fusion fragments ofthermonuclear reactions as of helium atoms in the first wall material at operating fusion reactor
should be. Therefore, the study of processes of accumulation and adsorption-desorption processesof light gases and especially of tritium is essential [3, 4]. An another important problem for modern
energetic complexes and engines is the storage of hydrogen in metal and alloys for accumulation ofhydrogen [5-7]. Besides that it is well known that rhenium ion can adsorb up to nine hydrogen ionsand create chemical composition complex as Re H 92 , i.e. may be such triple alkaline-rhenium
hydride like K2ReH9 (or deuteride-K2ReH9) can be used for hydrogen-deuterium storage. The use of
installations as the "Plasma Focus" for high-power plasma streams and study its effects on materials
is also very relevant in terms of modeling of such processes. The aim of this paper is to study the79

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propagation of shock waves in the metal foils on the effects caused byredistribution and accumulation of deuterium or hydrogen atoms
under the deuterium plasma bombardment.

theprocessesof

2. Research technique and results
The studies were performed using "Plasma Focus" set-up (PF-4) of Lebedev Physics Institute of
RAS [3, 4, 8-13]: the energy of the capacitor battery is 3.6-4 kJ, the maximum current ≈ 400 kA, theplasma flow velocity up to 108 cm/s, the plasma density up to ≈1018 cm-3, the plasma pulse durationof 50-100 ns, the energy flux density up to 108–1010 W/cm2, the neutron yield up to 108 neutrons
per pulse, the time between pulses of at least 5-6 minutes. The choice of hydrogen and deuterium
plasma was due to the possibilities of further measurements with the detection of elasticallyscattered recoil (elastic recoil detection - ERD-[14]) concentration profiles of hydrogen anddeuterium atoms after plasma treatment of the targets consist on the multilayer
metallic foils and combinations of other material, including non metallic foils [9-13]. A scheme ofthe elements of the PF-4 set-up is presented in Fig.1.

Fig.1. The scheme of the elements of the FS-4 [8] for irradiation of samples using the example of second
generation high temperature superconductor (HTSC) sample (the example)[8].

It is seen from Fig.1, near the target’s set of foils, which is schematically shown in Fig.2 [9-13],
cumulative jet stream can be focused to a relatively small surface. The density of a pulsed plasma
power on the target can be varied by changing of the distance between tungsten insert and target(Fig.1 and Fig.2). In our experiments that distance was 35 mm.

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Fig.2. The scheme of PF-4 pulse high temperature plasma action on the set of foils. Here 1 –holder for theset of foils, 2 - front aperture diaphragm with round hole (10 mm or 15 mm in diameter), 3, 4 - clamping
plate, and from 5-1 to 5-6 a set of six foils.

Deuterium plasma was used at our experiments to study of shock wave action on chosen materialsof foils [9-13]. Set of foils consisted on six tightly pressed Re-Mo foils with chemical composition
50 at.% of Re and 50 at.% of Mo metals. Thickness of each foil was 50 μm, i.e. whole thickness offoil set was 300 μm. The number of plasma pulses was 15. Deuterium pressure in the PF-4 chamber
was 2 Torr. The measurements of the neutron yield from fusion D-D reactions were carried out
using activating neutron detectors (see, as example [14]) during bombardment by deuterium pulse
plasma. The yield of neutron was measured and measured level was a little higher than background,
i.e.
the
yield
of
neutronsfrom
D-D
reaction
took
place.
1
2 1
2 1
2 1
2
Let us denote the appropriate set of foils, as Re-Mo-1 , Re-Mo-2 , Re-Mo-3 … Re-Mo-6 (see [9- 13]). Here top indexes correspond to nearer and futher surfaces of foils to PF-4. The
measurements of depth concentrations of introduced deuterium ions from plasma and initialhydrogen atoms which usually present in metals and alloys were carried out using elastic recoil
detection method (ERD) [15].
Energy [keV]

100

200

300

400

500

600

700

800

900 1000 1100 1200

Re50-Mo50 -15 PF-4 pulses

30
DE014.DAT
Simulated

28
26

Concentrations, at.%22
20CountsHydrogen,CH<0.164x1021 H/m2
Deuterium (x10),
CD<0.011x1021 D/m2

4

24

18
16
14
12
10
8
6
4
2
0
0

50 100 150 200 250 300 350 400 450 500 550 600 650 700 750

ChannelFig.3. Spectrum of elastic recoils detection ofhydrogen and deuterium from the balknear the surface of 1Re-Mo-1 foil.

3
2
1
0

0

5
10
17
2
Depth, x10 at/cm

15

Fig.4. Depth distribution of hydrogen anddeuterium atoms from the bulk near
near the surface of 1Re-Mo-1 foil.
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The ERD spectra for first three Re-Mo-foils together with the depth distributions of deuterium andhydrogen by pairs are presented in Figs.3- 4; Figs.5- 6 and Figs.7- 8, respectively. The ERD spectra
were obtained using the analyzing beam of helium ions with energy 2.3 MeV at grazing angle ofincidence on the sample of 150 with an electrostatic generator EG-5 in the SINP of MSU.
Processing of spectra was carried out using a standard simulation program-processing SIMNRA
6.05. Note that the projected range of helium ions Rp = 0.90 ± 0.36 μm, where the calculation ismade using the program TRIM-2007.

Concentrations, at.%

Re50-Mo50 -15 PF-4 pulses

Fig.5. Spectrum of elastic recoils detection ofhydrogen and deuterium from the balknear the surface of 1Re-Mo-2 foil.

Hydrogen,CH>1.3175x1021 H/m2
Deuterium (x10),
CD<0.0116x1021 D/m2

6
4
2
0

0

10
20
30
17
2
Depth, x10 at/cm

40

Fig.6. Depth distribution of hydrogen anddeuterium atoms from the bulk near
near the surface of 1Re-Mo-2 foil.

Re50-Mo50 -15 pulses PF-4

Concentrations, at.%12
9

Hydrogen,CH>3.71x1021 H/m2
6
Deuterium (x10),21
23 CD>0.011x10 D/m
0

0

10

20

Depth, x10

Fig.7. Spectrum of elastic recoils detection ofhydrogen and deuterium from the balknear the surface of 1Re-Mo-2 foil.

17

30
2
at/cm

40

Fig.8. Depth distribution of hydrogen anddeuterium atoms from the bulk near
near the surface of 1Re-Mo-2 foil.

All three of the ERD experimental spectra are represented for more visual representation of theobserved effect - deep penetration of deuterium in the set of Re-Mo-foils and also the deep changesof hydrogen concentrations too. The integral concentrations of deuterium and hydrogen in bulk Re82

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Mo alloy near the nearest surface to PF-4 are presented in Figs. 4, 6 and 8. It is necessary to notethat maximum depths of recoils which can be studied by ERD analysis are less than R p <1 μm.
Summary of these values are, as well, presented in Table 1.
Table 1. Integral concentrations in each foils of deuterium atoms, introduced into foils from deuterium
plasma of PF-4, and concentrations of hydrogen atom spreading measured by ERD analysis.

Maximum concentrationof hydrogen near surface
of foils
Integral concentration of
deuterium, СD
Integral concentration ofhydrogen, СНFirst foil in set,
1
Re-Mo-1
4%

Second foil in set,
1
Re-Mo-2
7%

Third foil in set,
1
Re-Mo-312%<0.011·1021 D/м2

<0.012·1021 D/м2

>0.021·1021 D/м2

0.164·1021 H/м2

>1.32·1021 H/м2

>3.71·1021 H/м2

As can be seen in all the foils deuterium atoms are present (see also ERD spectra - Figs. 3, 5 and 7).
More interesting fact is the presence of hydrogen with increasing of maximum concentrations andintegral
concentrations
in
the
each
following
foil
in
set.
It should be noted that the direct impact of deuterium plasma due to contact with the samples fromthe lateral surfaces of the foil set was completely excluded by the fact that all three Re-Mo foils(position 5-1, 5-2 and 5-3 in Fig. 2) was held tightly to one another between the front aperture
diaphragm 2 and clamping plate 4 (see Fig. 2). In addition, at high concentration of deuterium andhydrogen atoms on the surface of the all three foils was observed a characteristic colored spot witha diameter of 10 mm, which corresponds exactly to the diameter of the entrance
aperture (see also [9 - 13] and [16]).
3. Conclusion
The ERD studies of six Re-Mo foil set (with thickness of each foil 50 μm) after exposure by 15
pulse high-temperature deuterium plasma using installation PF-4 were carried out. It is establishedthat there were transport of introduced into set of foils deuterium ions from deuterium plasma andpresented in initial foils hydrogen atoms to large depths into all three measured foils.
Addition concentrations of deuterium and hydrogen atoms in volumes near the surfaces of each
three foils changed the metallic color of initial foil surfaces nearer to PF-4 to blue color after actionof deuterium plasma (see also [9 - 13] and [16]). These three spots on three first foils have adiameter exactly equal to diameter of front aperture diaphragm (see Fig. 2, detail position 2).
Surface and integral concentrations of hydrogen are increased from foil to foil very significantly(see Table 1).
The effect of ultra-deep penetration of hydrogen and deuterium can be explained by the influence ofpowerful shock waves [1 - 4, 8 - 13]. This explanation is confirmed by possible accelerated
diffusion of impurities in the presence of external driving forces F (see [17, 18]). In this case thediffusion laws ought to be presented in the form (see [17], page 11), where for the one-dimensional
case the operator  :
X(1)
J   DC   V F ,C DC )     V F ,
t

(2)

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

where the external driving force F imparts to each atom the average additional velocity V F and α
is the proportionality factor. The average velocity of each atom V F can be compared to the speedof propagation of the shock wave exceeding by several times the speed of propagation of the soundin a material [1 - 4]. As is known, under intense pulse action an elastic wave begins to propagate in
the material and transforms, at a certain depth Х0 depending on the material and pulse power
density on the surface, into a shock wave with an abrupt front – a compression-extension wave
behind the shock wave front. One can also make the following estimates. The velocity of sound inmetals exceeds V ≥ 2.0∙103 m/s, plasma pulse duration is of the order t = 50÷100 nanoseconds,
consequently, the maximal depth of transfer of light impurities of hydrogen and deuterium (XM) can
exceed the value XM = V∙t > 100÷200 μm. The estimated value of the hydrogen penetration depth isin the order-of-magnitude agreement with the experimental values in this paper and in [9 - 13].
References
1. V.E.Fortov. Extreme states of matter on earth and in space. Fizmatlit, 2008, 264 p.
2. V.E. Fortov. Extreme states of matter. Fizmatlit, 2010, 304 p.
3. Encyclopedia of the low-temperature plasma. Series B, helper applications, databases, and
V. IX -3, edited by VA Gribkov, M., ed.: JANUS-K, 2007, 591 p.
4. L.I. Ivanov, N.N. Pimenov, V.A. Gribkov. Physics and Chemistry of Materials Processing,
2009, № 1,. 23 p.
5. Handbook of Hydrogen Storage, New Materials for Future Energy Storage. Edited by Michael
Hirscher, Handbook of Hydrogen Storage, WILEY-VCH Verlag GmbH & Co. KGaA, 2010, 341
p.
6. Hydrogen in Metals, Volumes 1. Basic Properties. Edited by G. Alefeld and J. Volkl, SpringerVerlag, Berlin-Heidelberg-New York, 1978; Izd. M.: "Mir", 1981, 475 p.
7. Hydrogen in Metals, Volumes 2. Applied aspects. Edited by G. Alefeld and J. Volkl,
Springer-Verlag, Berlin-Heidelberg-New York, 1978; Izd. M.: "Mir", 1981, 430 p.
8. L.H. Antonova, I.V. Borovitskaya, P.V. Gorshkov, et.al. Reports of the Russian Academy of
Sciences, T. 428, № 4,. 471-473, 2009, p.471
9. A.Yu. Didyk. Preprint P14-2011-87, Dubna, JINR, 2011, 14 p.
10. A.Yu. Didyk. Preprint P14-2011-88, Dubna, JINR, 2011, 14 p.
11. A.Yu. Didyk, L.I. Ivanov, O.N. Krokhin et.al.. Reports of the Russian Academy of
Sciences, 2011 (in press).
12. A.Yu. Didyk, I.V. Borovitskaja, R. Wiśniewski et al. Surface. X-ray, Synchrotron and Neutron
Techniques, 2011 (in press).
13. A.Yu. Didyk, R. Wiśniewski, L.I. Ivanov et al. Surface. X-ray, Synchrotron and Neutron
Techniques, 2011 (in press).
14. I.V. Volobuev, V.A. Gribkov, S. Denus et al. Brief Communications in Physics, Moscow,
1987, № 11, p.32.
15. V.V. Zatekin, V.S. Kulikauskas, L.S. Novikov et al. Surface. X-ray, Synchrotron and Neutron
Techniques, 2008, № 4,. p.23.
16 F.J.A. Den Broeder, S.J. Van der Molen, M. Kremers et al. Nature 1988, No 394, 656 p.
17. B.S. Bokshtein. Diffusion in metals. M.: Metallurgiya, 1978, 248 p.
18. V.Ya. Geguzin. Diffusion zone, M.: Metallurgiya, 1976, 320 p.

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1.P5.
COORDINATION COMPOUNDS OF BIOLOGICALLY ACTIVE
N-CONTAINING HETEROCYCLIC LIGANDS
Z.Ch.Kadirova1, Kh.T. Sharipov1, Sh. Juraev1, N.A. Parpiev2
Tashkent Chemical-Technological Institute, Navoi St. 32, Tashkent, Uzbekistan
National University of Uzbekistan named by Mirzo Ulugbek, Vuzgorodok, Chemical Faculty, Tashkent,
Uzbekistan,zuhra_kadirova@yahoo.com

The synthesis of rhenium coordination compounds strongly depends on reaction conditions,metal precursor and ligand nature. The rhenium compounds with some biologically active
heterocyclic ligands were prepared and characterized by spectral methods and thermal analysis. The
2-amino-1-methyl-1H-benzimidazole-2 (L1), 3 (benzimidazole-2-yl) - propanol-1 (L2), N-hydroxy3-pyridinecarboxamide (L3), 7-methoxy-1-methyl- 4,9-dihydro-3H –pyrido [3,4-b] indole (L4)ligands contained the 5- and 6-membered heterocycles are existed in stable protonated forms in acidsolution.

O(CH2)2CHOH

NH2
NH

N
1

L

CH3

C NHOH

N

N

N

L2

H H H

L3
H

H3CO
NH
L4

CH3

The reaction of hexachloridorhenate (IV) with L1-L4 yields to formation hexachlororhenates(IV) consisted from the complex metaloanions and the protonated molecules of organic ligands ascations.
These salts have poor solubility in water and can exist in the concentrated acid solution that
can have application in extraction of rhenium by precipitation.
The synthesized compounds showed the solid-phase dehydrogalogenation and thetemperatures of thermal effects depended on structure of organic cations.
The Re(V) precursor ReOCl3(PPh3)2 is reduced by PPh3 in the presence of L1, giving goodyields of rhenium(III) complexes. Good solubility of complexes in organic solvents is used forrhenium extraction.
The composition and structure of complexes were established on the base of elemental andthermal analysis, IR, NMR- data.

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1.P6.
CHELATION OF RHENIUM (V) WITH 3-ETHYL-4-METHYL-1,2,4TRIAZOL-5-THIOL IN 3 MOL/L HCL MEDIUM
N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjonov

Tajik National University. Dushanbe. azimjon51@mail.ru

Keywords:. rhenium(V), 3-ethyl-4-methyl-1,2,4-triazoltiole-5-thiol
Abstract
The process of chelation of rhenium (V) with 3-ethyl-4-methyl-1,2,4-triazoltiole-5-thiol in 3 M HCl
medium in the range 273-338K. The values of stepwise formation constants of all forms ofcomplexes formed in system H2[ReOCl5] - 3-ethyl-4-methyl-1,2,4-triazoltiol - 3 M HCl. The valuesof the thermodynamic functions of complexation process are estimateed.
Introduction
Conduction researches in solutions can to a certain extent shed light on the mechanisms offormation of complex compounds. To perform these studies, one of the available methods is
potentiometric titration with ligand redox electrodes based on sulfur-containing compounds andtheir oxidized forms. Ligand environment designed electrode systems play a special role in theformation of sulfur-containing compounds of azoles and their oxidized forms. Representative of thisclass of compounds are 1,2,4-triazoltiol and its derivatives, which have been used as a substrate fora redox ligand electrodes in the middle of the eighties. By potentiometric titration processes
complexation of rhenium (V) with 1,2,4-triazoltiole and some of its alkylderivates were studied.
The authors of [1] developed a reversible ligand electrode based on 3-ethyl-4-methyl-1,2,4triazoltiolt-5-thiol and its oxidized form. The purpose of this paper is to study the process ofchelation of rhenium (V) with 3-ethyl-4-methyl-1,2,4-triazoltiole-5-thiol in 3 M HCl medium in the273-338K temperature range.
Experimental
To determine the stepwise formation constants of complexes of rhenium (V) with 3-ethyl-4-methyl1,2,4-triazoltiolom-5-thiol in 3 M HCl medium in the temperature range 273-338K using
potentiometric method, which is described in [1] in detail. The equilibrium concentrations of 3ethyl-4-methyl-1,2,4-triazole-5-thiol was calculated using the formula:Еисх  Еi
1 Vисх lg C L  lg исхlg[L]=
4
2 Vобщ
1,983  10  T
where Eish - the equilibrium potential of the source system in the absence of rhenium (V); Ei
is the equilibrium potential of the system at a given point of titration, CL - initial analyticalconcentration of ligand; Vish/Vobsch- ratio of the original volume of the total, and T - the temperatureof the experiment. Bjerrum formation function was determined by the formula:n = С L  [ L]
C Re(V )where CL - the concentration of 3-ethyl-4-methyl-1,2,4-triazoltiole at each point of the titration; [L]- equilibrium concentration of 3-ethyl-4-methyl-1,2,4-triazoltiole at each point of the titration;
СRe(V) - the concentration of rhenium (V) at each point of the titration. All calculations were
performed using «Pentium-IV» computer.
Results and discussion
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

Studies have shown that during the addition of H2[ReOCl5] to 3-ethyl-4-methyl-1,2,4triazole-5-thiol in 3 M HCl medium is a sequential change in color of the solution from red topurple, then to the blue and green. Adding to the green solution of 3-ethyl-4-methyl-1,2,4-triazole5-thiol leads to the opposite change in color of the solution. This fact confirms the aliasing ofcomplex rhenium (V) 3-ethyl-4-methyl-1,2,4-triazole-5-thiol, and indicates the reversibility of thisprocess. In the titration system consisting of 3-ethyl-4-methyl-1,2,4-triazole-5-thiol and its oxidized
form solution H2[ReOCl5] observed increase in the magnitude of the equilibrium potential, whichindicates that participation in complexation with rhenium (V) 3-ethyl-4-methyl-1,2,4-triazole-5thiol, but not its oxidized form. At each point of the titration, equilibrium is established within 5-10
minutes. As an example, Table 1 shows the experimental results to determine the function of
education 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes of oxorhenium (V) chloride in medium
3 mole/l HCl at 273K.
Table 1. Determining the formation function of 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes ofoxorhenium (V) chloride in 3 M HCl medium at 273K

№
1
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
1
24.
25.
26.
27.
28.

СRe(V) 104

СL 102
mol/l

2
14,1
16,8
19,4
22,0
24,6
27,1
29,6
32,1
34,5
36,9
39,2
41,6
43,8
46,1
50,5
55,9
61,1
66,1
71,0
75,7
88,03
84,7
97,2
2
105,0
119,3
132,1
149,1
168,3

3
1,321
1,311
1,301
1,292
1,282
1,273
1,264
1,254
1,246
1,297
1,228
1,220
1,211
1,203
1,186
1,167
1,148
1,129
1,111
1,094
1,077
1,061
1,014
3
9,86
9,33
8,86
8,24
7,53

 E, мВ

[L]·104

_
n

4
19,55
22,80
24,90
28,35
34,00
39,10
40,40
48,00
49,35
53,00
60,30
61,55
64,30
67,00
73,55
84,00
89,70
94,36
103,00108,80110,75
112,60
119,304
120,80122,15
114,40104,50
64,40

5
58,67
50,91
46,39
39,92
31,28
25,10
23,66
17,07
16,06
13,71
10,01
9,46
8,39
7,46
5,58
3,67
2,78
2,26
1,55
1,20
1,10
1,01
0,74
5
0,69
0,63
0,85
1,25
6,59

6
5,22
4,79
4,32
4,05
3,94
3,77
3,47
3,38
3,15
2,98
2,87
2,71
2,57
2,45
2,30
2,02
1,83
1,67
1,54
1,43
1,33
1,24
1,04
6
0,93
0,78
0,66
0,54
0,41

Potentiometric titration curves of 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes ofrhenium (V) formation at different temperatures are shown in Figure 1. It is seen that the curves of87

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 20113-ethyl-4-methyl-1,2,4-triazole-5-thiol rhenium (V) complexes formation, without changing its
shape with increasing temperature, shifting toward lower values of -lg[L], which indicates that
identity of the process of complexation in the range 273-338K. Established that during theinteraction of rhenium (V) 3-ethyl-4-methyl-1,2,4-triazole-5-thiol in 3 M HCl medium in thetemperature range 273-338K in series form five complete form.

Figure 1. Curves education 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes of rhenium (V) in
medium 3 mole/l HCl at temperatures: 1-273; 2-288, 3-298, 4-308; 5-318, 6-328, 7-338K.

Determined by the method of Bjerrum formation curve, the values of pKi 3-ethyl-4-methyl1,2,4-triazole-5-thiol complexes of rhenium (V) in 3 M HCl medium are presented in Table 2.
Table 2. PKi values 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes of rhenium (V) in medium 3
mole/l HCl at 273-338K

Т,К
273
288
298
308
318
328
338

рК1
3,61
3,59
3,01
2,83
2,80
2,66
2,50

рК2
3,82
3,70
3,63
3,60
3,40
3,25
3,10

рК3
3,12
2,99
2,89
2,84
2,75
2,67
2,58

рК4
2,69
2,54
2,41
2,36
2,18
2,26
2,21

рК5
3,00
2,25
2,16
2,13
2,10
2,06
2,03

The data presented in Table 2 show the closeness of the numerical values of the constants ofstep formations. All stepwise stability constants decrease with increasing temperature, indicatingthat the exothermicity of the complexation process. Reducing the quantities of step formation
constants 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes in the 3 M HCl medium with anincrease in temperature can be explained by the fact that with the rise of temperature thecompetition between chloride ions and 3-ethyl-4-methyl-1,2,4-triazole-5-thiol molecules increaseson the one hand, and the other the competition between water molecules and these organic ligand
for a place in the coordination sphere increases also. Regardless of the chloride ions with water88

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

molecules or competition takes place with increasing temperature, the occurrence of the moleculesof 3-ethyl-4-methyl-1,2,4-triazole-5-thiol the internal sphere of the complex is difficult.
With the use of certain quantities of pKi entities curves at different temperatures using thetemperature coefficient were calculated thermodynamic functions of complexation process rhenium(V) 3-ethyl-4-methyl-1,2,4-triazole-5-thiol in medium 3 mole/l HCl, which are presented in Table 3.
Table 3. Thermodynamic functions of the educational process 3-ethyl-4-methyl-1,2,4-triazole-5-thiol
complexes of rhenium (V) in 3 M HCl medium.

№
1
2
3
4
5

The composition ofcompounds[ReOLCl4][ReOL2Cl3][ReOL3Cl2]+[ReOL4Cl]2+[ReOL5]3+ΔН,кJ/mole-21,27-14,18-11,49-8,51-21,99ΔG,
кJ/mole-20,71-16,49-13,75-12,32-13,38ΔS,
J/mole·К
-1,88
9,26
7,58
12,8
-28,9

The data in Table 3 show that the first phase of complex value of ΔS is negative, and thesecond is positive. The value of ΔG with the increase of the number of coordinated molecules of 3ethyl-4-methyl-1,2,4-triazole-5-thiol, becomes less negative, which is associated with increased
steric hindrance at the following occurrence of the molecules of 3-ethyl-4-methyl-1,2,4-triazole-5thiol in the inner sphere of complexes.
The values of stability constants were used to calculate the distribution curves of allcomplex forms, resulting in the rhenium (V) - 3-ethyl-4-methyl-1,2,4-triazole-5-thiol - 3 M HCl in
the temperature range 273 - 338K, which allowed to define the field dominance of a complex shape.
As an example, Figure 2 shows the distribution curves of the 3-ethyl-4-methyl-1,2,4-triazole-5-thiol
complexes of rhenium (V) in 3 M HCl medium at a temperature of 273K.

Fig.2. Distribution curves of 3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes of rhenium (V) in 3 M
HCl medium at 273K.

Analysis of the distribution curves shows that with the increasing of number of coordinatedmolecules of the organic ligand, equilibrium value of the maximum yield of complex forms for the
3-ethyl-4-methyl-1,2,4-triazole-5-thiol complexes of rhenium (V) in 3 M HCl medium changes
monotone.

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References
1.Aminjanov AA. Ligand electrodes and their use for the study of complex formation. //Interparticle interactions in solutions. Dushanbe, 1991,-C.6-17.
2. Aminjanov AA., Akhmedov K.U. Investigation of the process of complexation of rhenium (V)with 1,2,4-triazoltiolom-3 (5) in the medium 6 mol / l HCl spectrophotometrically. //Complexation in solution. , Dushanbe, 1991, p.58-65.
3. Aminjanov AA, Kurbanov NM The study of complexation of rhenium (V) with 3-methyl-1,2,4triazoltiolom-5 at different temperatures. // Zhurn.neorgan.himii. -1990. -T. 35, № 3. -C. 672678.
4. Aminjanov AA, SM Safarmamadov Complexation of rhenium (V) with 4-methyl-1 ,2,4triazoltiolom-5 among 6 mol / l HCl / / Zhurn.neorg.himii. -1993. -T.38, № 2. -S.291-295.
5. Aminjanov AA, SM Safarmamadov The study of complex formation of rhenium (V) with 4methyl-1,2,4-triazoltiolom-5 medium 6 mole/l HBr. // Izv.vuzov. Chemistry andhim.tehnologiya. -1993. -T.38, № 8. -P.34-38.
6. Aminjanov AA Gagieva SC The study of complexation of rhenium (V) c 3-methyl-4-phenyl-1,2,4-triazoltiolom-5 among 6 mole/l HCl. // Russ. inorganic. himii.-1996, v.46. № 11.-S.19701976.
7. AA Aminjanov, KV Romer, GD Zegzhda, JN Kukushkin. Potentiometric study of complexationof rhenium (V) with 1-methyl-2-merkaptoimidazolom / / Journal of Inorganic Chemistry. ,Moscow, 1975.-v.20, № 1.-S. 115-117.

N.Kravchenko, Prof. M. Ozawa, E. Johnstone, E. Nazarov at the Award Ceremony

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1.P7.
COMPLEXATION IN THE SYSTEM Re (V) ÷ 1-METHYL-2MERKAPTOIMIDAZOL ÷ 8 M HCL
K.S. Mabatkadamova, N.G. Kabirov, S.M. Safarmamadov, A.A. Aminjonov
Tajik National University. (Rudaki Avenue 17., Dushanbe, Republic Tajikistan)

Overview:
The process of chelation of rhenium (V) with 1-methyl-2merkaptoimidazolom in 8 mol/l HCl
medium was studied by potentiometric titration method. Stepwise formation constants ofoxochloro-1-methyl-2-merkaptoimidazole complexes with rhenium (V) and the magnitude of thethermodynamic functions of complexation process were determined.
Keywords: stability constant, renium (V), complexation, potentiometric titration, thermodynamic
functions
In [1,2] the optimal conditions for the synthesis of complexes of rhenium (V) with 1-methyl2-mercaptoimidazole in the medium of 6 M HCl were determined. It is shown that in thisenvironment, depending on the ratio of initial reagents, rhenium (V) forms complexes with 1methyl-2-mercaptoimidazole of compositions [ReOL2Cl3]H2O and [ReOL4Cl]Cl22H2O. The
composition and structure of the synthesized complexes established by elemental analysis, IR
spectroscopy and conductometric methods. The study of IR spectra of complexes obtained showedthat the molecule of 1-methyl-2-merkaptoimidazole in forming complexes behave as monodentate
ligand coordinated to rhenium (V) through the donor atom of sulfur. In [3] Kukushkin et al
published data on the synthesis of two- and tetra-complexes of oxo rhenium (V) bromide with 1methyl-2-mercaptoimidazole in the 6 M HBr medium. In [1] the study of the oxidation of 1-methyl2-mercaptoimidazole and creation on the basis of its redox electrode is also reported. Using of thesystem studied in the process of rhenium (V) chelation with 1-methyl-2-mercaptoimidazole in the 6
M HCl medium. The author [4] studied the complexation of rhenium (V) with 1-methyl-2mercaptoimidazole in 7.4 M HCl medium in the temperature range of 273-338K. It was found thatthe increasing of HCl concentration from 6 to 7 M leads to an increase in the stability constants ofmonosubstituted complex of rhenium (V). However, for other forms of complex with increasing
concentrations of HCl, a decrease values of their formation constants. In this regard, for a moredetailed setting influence of the concentration of HCl in the process of chelation of rhenium (V)with 1-methyl-2-mercaptoimidazole, we carried out the research of rhenium (V) complex with theorganic ligand in the 8 M HCl medium.
Experimental partIn the potentiometric method of determining the formation constants in HCl solution with aconcentration 8 M, containing a redox electrode on the basis of 1-methyl-2-mercaptoimidazole andits oxidized form platinum electrode was immersed. As a reference electrode silver chloride
electrode was used. After reaching a constant value of building the system was titrated with
[ReOCl5] solution 2 to 8 M HCl. In the titration of RSSR / RS, where RS-1-methyl-2mercaptoimidazole hydrochloric acid solution [ReOCl5] the potential of the system was sets
constant during 5-10 minutes.
Equilibrium concentration of 1-methyl-2-mercaptoimidazole was calculated according topotentiometric titration using the equation:lg[ L] Eисх.  Ei
1 Vисх.
исх.

lg
C

lg
,
L
4
2
V
1,9837 10 T
общ.

where Eorig - the original equilibrium potential system in the absence of rhenium (V); Ei equilibrium potential of the system at a given point of titration; CL-initial analytical concentration of91

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

ligand; Vorig / Vtot - the ratio of the initial volume to the total volume; T - the temperature of theexperiment in K. Having determined the equilibrium concentration of 1-methyl-2mercaptoimidazole at each point of the titration, the formation function was calculated by theequation:n

C L  [ L],C МеIt should be noted that all the calculations to determine the equilibrium concentration of theligand, the function of education, and thermodynamic functions of the mole fractions was
performed on a specially designed computer programs for Pentium-4.
Results and discussion
As an example, in table 1 shows the experimental data to determine the function of education 1methyl-2-mercapto-imidazole complexes of oxo rhenium (V) chloride in the 8 M HCl medium at
273K.
The value of the constant formation of complexes with half-integer values of the complexation
function was estimated by building n = f (-lg [L]) deendence for each specific temperature on thebasis of the data in table 1.
Figure 1 shows the formation curves of oxochloro-1-methyl-2-merkaptoimidazole complexes
with rhenium (V) in the 8 M HCl medium at different temperatures.

Fig. 1. Curves formation 1-methyl-2-mercapto-imidazole complexes of oxo rhenium (V) chloride in the 8 M
HCl medium at 273 (1), 288 (2), 298 (3), 308 (4), 318 (5), 328 (6) and 338 K (7)As seen from fig. 1, the curves of formation, almost without changing its shape as thetemperature rises only shifted towards higher values of the equilibrium concentration of 1-methyl-2mercaptoimidazole which indicates the identity of the process of complex formation in thetemperature range 273-338K.
In the range 273-338K for the system H2[ReOCl5] - 1-methyl-2-mercaptoimidazole in 8 M HCl, themaximum is set equal to 4.7, which indicates the formation of five complex forms in this system.
Comparison of the formation curves of 1-methyl-2-mercaptoimidazole complexes of rhenium (V)from the 8 M HCl medium with the data obtained by the author [2], in 7 M HCl shows that
increasing concentrations of HCl to 1 M leads to a shift formation curve towards lower values of theequilibrium concentration of the ligand, although the shapes of the education differ little from eachother.
92

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Table 1. Determining the function of education 1-methyl-2mercaptoimidazole complexes of oxo rhenium (V) chloride in the 8 M
HCl medium at 273 K
ΔE, мВ

CL, mol / lCRе, mol / l[L], mol / l

n

1
50.51
58.34
73.86
74.20
82.12
84.63
87.13
93.76
99.41
102.23105.25108.44107.30109.34116.92121.42125.91133.43137.51138.80143.06147.25151.56156.79164.54169.57170.87176.08179.21
184.61205.48210.22211.36214.27222.25218.03218.01

2
0.02410.02380.02360.02340.02320.02300.02280.02240.0221
0.02170.02100.02000,01950.01860.01810.01740.16800.01630.01540.01450.01380.01310.01250.01240.01220.01200.01130.01120.01010.01010.01950.01900.01840.01600.01590.01580.015630.004460.004910.00530
0.00579
0.006220.006640.00746
0.00826
0.009020.010400.01251
0.013760.01551
0.01659
0.018110.019510.02030
0.022400.024200.025800.02725
0.02856
0.02975
0.03080
0.03180
0.03204
0.032540.03301
0.033620.033400.037410.03860
0.03979
0.03380
0.033900.03400
0.0341040.00281838
0.00199526
0.00102329
0.00100000
0.00070795
0.00063096
0.00056234
0.00041687
0.00032359
0.00028184
0.00023988
0.00019953
0.00020417
0.00015849
0.00012589
0.00010000
0.00007079
0.00005623
0.00004467
0.00003981
0.00003162
0.00002512
0.00001995
0.00001585
0.00001122
0.00000891
0.00000794
0.00000631
0.00000501
0.00000398
0.00000316
0.00000251
0.00000158
0.00000178
0,00000126
0.00000110
0.00000071

5
4.59
4.18
3.87
3.80
3.70
3.60
3.50
3.40
3.20
3.10
3.00
2.95
2.80
2.55
2.50
2.43
2.25
2.15
2.10
2.00
1.90
1.80
1.60
1.50
1.40
1.30
1.25
1.10
1.05
0.95
0.82
0.65
0.60
0.50
0.42
0.24
0.18

Formation curves of step stability constants oxochloro-1-methyl-2-mercapto-imidazole complexesof rhenium (V) in the 8 M HCl medium, determined by the method of Bjerrum, are presented intable 2.
Decrease in the values of the formation constants with increasing temperature (Table 2)
indicates the exothermicity of the complexation process. However, the temperature factor affects
their values differently. Since the value of K1, with increasing temperature from 273 to 338K, was
33 fold decreased, and the quantities K2 and K3 was, respectively, 10.7 and 10.9 fold decreased.
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Table 2.Formation constants oxochloro-1-methyl-2-mercaptoimidazole complexes of rhenium (V) in the 8 M
HCl medium at 273-338 K.

Т, К
273К
288К
298К
308К
318К
328К
338К

K1
1.1∙106
5.6∙105
3.5∙105
2.1∙105
1.1∙105
9.1∙104
3.3∙104

K2
7.4∙104
4.4∙104
3.6∙104
2.5∙104
1.4∙104
9.3∙103
6.9∙103

K3
9.3∙103
6.4∙103
4.6∙103
3.2∙103
2.3∙103
1.9∙103
8.5∙102K4
1.9∙103
1.3∙1031.0∙103
7.5∙102
3.5∙1021.1∙1028∙101

К5
3.1∙102
2.6∙102
1.6∙102
1.4∙102
9∙101
6∙101
3∙101

This experimental finding can be explained by the fact that the formation of mono substitutedcomplex proceeds with a large release of heat than the two- and tri-substituted complexes, asevidenced by the reaction of ΔH these complexes are calculated by us using the temperature
coefficient. Comparison of the PK1 for 1-methyl-2-mercaptoimidazole complexes of oxo rhenium(V) chloride in the 8 M HCl medium with similar values obtained in the 7 M HCl medium [2]shows that changing the acid concentration in 1 M of leads to the decrease in the value of all thestability constants of step. The author of [2], studying the complexation of rhenium (V) with 1methyl-2-merkaptoimidazole notes that the change in concentration of HCl from 6 to 7 M leads
only to an increase in the stability constant of monosubstituted complex, and the other constants are
reduced. The decrease of the stability constants with increasing HCl concentration can be explainedby an increase in competition for the coordination site between chloride ions and molecules of 1methyl-2-mercaptoimidazole. Formation constants 1-methyl-2-mercaptoimidazole complexes ofoxo rhenium (V) chloride curves defined by education we were used to estimate the thermodynamic
characteristics of complexation process by the temperature coefficient (Fig. 2).

Fig. 2. The dependence of the PKI = ƒ (1 / T) for 1-methyl-2-mercaptoimidazole complexes of oxo rhenium(V) chloride in the 8 M HCl medium.

Depending curces on the PKI 1/T in the temperature range 273-338 K, for all complex forms arelinear. The table 3 shows the values of the thermodynamic functions of the formation process 1methyl-2-mercaptoimidazole complexes of oxorhenium (V) chloride in the 8 M HCl medium. The
value of ΔS and ΔH on the all stages of complex formation is negative. Maximum heat releasesystem is observed during the formation of mono- and tetrasubstitued rhenium (V) complexes. The
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value of ΔG with increasing number of coordinating molecules of 1-methyl-2-mercaptoimidazole
becomes less negative, due to the space obstruction of the occurrence of subsequent molecules
organic ligand in the inner complex sphere.
Table 3. The values of thermodynamic functions of the educational process oxochloro-1-methyl-2mercaptoimidazole complexes of rhenium (V) in the 8 M HCl medium.

The
composition ofcompounds[ReOLCl4][ReOL2Cl3][ReOL3Cl2]+[ReOL4Cl]2+[ReOL5]3+ΔН, kJ / mol

ΔG, kJ / mol

ΔS, kJ / mol -1∙К

-39.37-28.79-26.82-36.48-26.39-31.36-25.55-20.74-16.45-12.53-26.89-10.84-20.41-67.20-46.55The values of formation constants were used to calculate the distribution curves of allcomplex forms, resulting in a system [ReOCl5] - 1-methyl-2-mercaptoimidazole in 8 M HCl. As an
example, figure 2 shows the curves of the distribution of all forms of complexes formed in thissystem at a temperature of 273K.

Fig. 2. The distribution curves 1-methyl-2-mercaptoimidazole complexes of oxo rhenium (V) chloride in the
8 M HCl medium at 273 K, where α0-[ReOCl5]2-, α1-[ReOLCl4]ˉ, α2-[ReOL2Cl3], α3 - [ReOL3Cl2]+, α4[ReOL4Cl]2+ α5-[ReOL5]3+.

The analysis of the distribution function of the temperature showed that with increasing
temperature, the output of all forms of complex decreases. These experimental data were used todevelop methods of synthesis of complex compounds of rhenium (V) with 1-methyl-2mercaptoimidazole.
Reference
1. K.V. Kotegov, A.A. Aminjanov, Yu.N., Kukushkin, T.V. Zegzhda / / JNCh Moscow. v.20, №
1, - p.115-117. (1975)
2. A.A. Aminjanov, Complex compounds of rhenium (V) c sulfur compounds azole series: Ph.D.
in Chemistry. / AA Aminjanov .- Leningrad, 1975. -20 Sec.
3. K.V. Kotegov, T.V. Zegzhda, A.A. Aminjanov, Yu.N. Kukushkin, The study of complexationof rhenium-V oxobromide with
1-methyl-2-merkaptoimidazole / / / JNCh.. T.22. № 10. S.2742-2743(1977)/
4. A.A. Aminjanov, Complex compounds of rhenium (V) with amide and tioamid ligands.
Dissertation of doctor of chemical sciences, Ivanovo (1992) 42p.
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SPECIATION OF TECHNETIUM IN SULFURIC MEDIA.
EFFECT OF -RADIATION FROM THE ARRONAX CYCLOTRON.
F. Poineau1, I. Denden2, R. Essehli2, K. German3, K. Czerwinski1 and M. Fattahi2
1- Department of Chemistry, University of Nevada Las Vegas, Las Vegas, USA
2 - Laboratory Subatech, School of Mines of Nantes, No 4 rue Alfred Kastler, Nantes, France,(e-mail: massoud.fattahi-vanani@subatech.in2p3.fr )3 - IPCE Russian Academy of Science, Moscow, Russia
The speciation of technetium in the sulfuric media has been performed under reducing
conditions and the effect of -radiation from the Arronax Cyclotron has been studied.
Characterization of the species has been performedby spectroscopic techniques (EXAFS, UVVisible). It was demonstrated that heptavalent technetium is very sensitive to reduction in sulfuric
media between 12 M to 18 M [H2SO4] and could be reduced to Tc(V) by MeOH. Reduction of
TcO3(H2O)2OH (Tc: 10 mmol, 15 M H2SO4) by MeOH (10 µl) is fast, the formation of a green
solution was observed. New “Tc-green” species were studied by UV-vis spectroscopy (bands at 390
nm and 715 nm) and XANES\EXAFS. Similar spectra obtained between 12 M and 18 M [H2SO4]. No

reaction was observed below 12 M [H2SO4].

Fig.1. XANES data for known Tc compounds and new
green Tc specie as a function of Tc oxidation stateFig.2. UV-visible spectra of TcO3(OH)(H2O)2
in 18 M [H2SO4] before (A) and after 18
min of -irradiation (B)The EXAFS spectroscopy data confirm the existence of monomeric octahedral complex(with one O atom at 1.60(2) Å: Tc=O characteristic of Tc(V), five O atoms at 2.04(2) Å : Tc-O; TcOH, Tc-H2O, Tc-O(S); and two S atoms at 3.23(3) Å : Tc…S indicative of two monodentate
bisulfate anions) being consistent with TcVO(HSO4)2(H2O)2(OH). It was also shown that
heptavalent technetium is unstable under -radiation in 18 M H2SO4 being reduced to
TcVO(HSO4)2(H2O)2(OH) by [H2SO4] radiolysis products.
Funding for this research was provided by a SISGR Grant from the U.S. Department ofEnergy under Contract No. 47824B. Use of the Advanced Photon Source was supported by the U.
S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No.
DE-AC02-06CH11357.
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1.P8.
SYNTHESIS, CRYSTAL STRUCTURE AND PROPERTIES OF
TRIPHENYLGUANIDINIUM TETRAOXIDORHENATE HEMIHYDRATE
A. Ya. Maruk*, M. S. Grigor’ev, K. E. German
Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences
Leninskii pr. 31, Moscow, 117071 Russia*E-mail: amaruk@list.ru

Triphenylguanidinium
tetraoxidorhenate
hemihydratewassynthesized([(C6H5NH)3C]ReO4 · 0.5H2O) and studied with X-ray diffraction. Also a number of physicalproperties were studied. Compound under study crystallizes in the triclinic system (space group P-1,
Z = 4, at 293 K: a = 9.8716(17), b = 14.093(2), c = 15.439(3) Å, α = 99.632(9), β = 101.802(9), γ =95.361(10) deg). The compound has no isostructural analogues. In all structures containing
triphenylguanidinium cation, found in the Cambridge Structural Database (CSD version 5.31,
August 2010), the position of the phenyl rings corresponds to the conformation that differ from thatobserved in the known compounds (p.e. [1, 2]). In the ([(C6H5NH)3C]ReO4 · 0.5H2O) structure
phenyl rings in triphenylguanidinium cations occupy the position corresponding to high-symmetry(С3h) conformation that has been never before observed, and this conformation is being realized inboth crystallographically independent cations.
Fig. Cation conformations
known from literature (A)and found in this study (B)A

B

Perrhenate anions are in the form of weakly distorted tetrahedra and do not differ from thoseanions described in the literature. The system of hydrogen bonds is presented by infinite branchedchains in the [110] direction, combining the two independent formula units.
The compounds under study is promising for conversion into a metal rhenium. In thisconnection thermal studies were carried out. The following physical properties were identified: theupper limit of thermal stability of triphenylguanidinium tetraoxidorhenate hemihydrate (393 K) andits enthalpy of dehydration (ΔHdegidr(393 K) = 10,0(3) kJ/mol), the melting point of anhydrous
triphenylguanidinium tetraoxidorhenate (448 K), and its enthalpy of melting (ΔHm(448 K) = 31,0(9)kJ/mol).
If the thermolysis is conducted in an atmosphere of inert gas (argon) and the sample issubjected to recrystallization annealing at a temperature above 1250 K, the solid product is
nanodimentional metal rhenium dispersed in a matrix of amorphous carbon. Chemical analysis
showed the dependence of the ratio of rhenium to carbon in the solid phase of process macrokinetic
options (the rate of temperature increase, the rate of inert gas flushing, water content in the system
and in the gas phase). If the thermal decomposition is carried out in an atmosphere of a reducing gas(eg. hydrogen), the solid product is almost pure metallic rhenium.
The work was supported by RFBR grant 09-03-00017-a.
1.
2.

Silva, P.S.P., Domingos, S.R., Silva, M.R. et al. // Acta Crystallogr. E.. V. 64. P. o1082 (2008).
Polyanskaya, T.M., Il’inchik, E.A., Volkov, V.V. et al. // Journal of Structural Chemistry. Vol. 49, No. 3, pp.
494-503, 2008

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1.P9.
SYNTHESIS AND CRYSTAL STRUCTURE OF [AnO2(HMPA)4](MO4)2(An = U, Pu; M = Cl, Tc, Re)
A.M. Fedosseev, M.S. Grigoriev
Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Moscow, Russia)

Synthesis was performed by using UO3 or PuO3·H2O as starting material, which wasdissolved in stoichiometric amount of aqueous solution of corresponding acid HMO4 withconcentration less than 0.1 M. Obtained solutions were dried at heating up to temperature less than
100oC and solid residue was dissolved in excess of hexamethylphosphortriamide(tris(dimethylamino) phosphine oxide, HMPA). Large elongated crystals were obtained during slow
evaporation of reaction mixture in a flow of air.
All the compounds crystallize in an orthorhombic space group Pbca and are isostructural
with earlier studied uranyl HMPA complexes with periodate [1], perbromate [1] and perclhorate [2]anions. Full structural data were available only for [UO2(HMPA)4](ClO4)2.
Crystal data for [PuO2(HMPA)4](ClO4)2 (Bruker KAPPA APEX II autodiffractometer,
MoKα radiation): a = 13.9939(4), b = 15.0970(4), c = 45.7102(13) Å at 100 K, Z = 8, R1 = 0.0463.

Molecular structure of [PuO2(HMPA)4](ClO4)2Interatomic distances in a series of isostructural compounds will be discussed.
References
1. Gusev Yu. K., Lychev A.A., Mashirov L.G., Suglobov D.N. Radiokhimiya (1985) 27, 412.
2. Nassimbeni L.R., Rodgers A.L. Cryst. Struct. Commun. (1976) 5, 301.

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1.Р10.
TRANSFORMATION OF Тс(VII) IN ACIDS: TcO3(OH)(H2O)2 andTcO3(H2O)3+ in HClO4 AND POLYMERIC Tc(VII) SPECIES IN SOLIDS AND
ACETONITRYLE SOLUTIONS
K.E. German 1, A.Ya. Maruk 1, F. Poineau2, Ph.Weck2,
G.A. Kirakosyan1, V.P. Tarasov1 , K. Czerwinski2, A. Sattelberger3
1

Frumkin Institute of Physical Chemistry and Electrochemistry of RAS (Moscow, Russia)
2
University of Nevada LasVegas (LasVegas, USA)
3
Energy Sciences and Engineering Directorate, Argonne National Laboratory, Argonne, IL 60439, USA

In course of our pertechnic acid investigation the common Tc(VII) – pertechnetate ionicform - was recently shown to decompose in 7-18M concentrated sulfuric acid solutions producing
the octahedral TcO3(OH)(H2O)2 species [1]. It was worth studying if other acids could make any
similar effect. Perchloric acid and nitric acid were chosen for this study.
The results differed considerably: in perchnloric acid (Fig.1) the transformation of Tc(VII)was similar to the observed in sulfuric acid [1], while no notable changes in UV and NMR spectra
were seen for Tc(VII) in nitric acid.
Some similarity of Tc(VII) speciation in sulfuric and perchloric acids was seen by EXAFS,
although the Tc(VII) solutions in HClO4 were not that resistant to synchrotron radiation.

Fig. 1. NMR-Tc99 shift (, ppm), and UV-vis spectra evolution(D at 350 nm) for Tc(VII) in 1-11M HClO4

The solid HTcO4 and its solutions in CH3CN were analyzed by 99Tc and 1H NMR in a fieldof 7.04 T. HTcO4 and its deuterated analog DTcO4 were prepared by oxidizing Tc metal in O2 at
500oC, dissolving Tc2O7 in H2O or D2O, the solution brought to dryness with Mg(ClO4)2. The
samples were dark red polycrystalline blocks. Elemental analysis gave the ratio H/Tc  1.
The 1H NMR spectrum of a fresh HTcO4 powder at 259 K showed two splitted signals: astrong signal at 5.6 ppm with the width at half-maximum of 400 Hz and a weak signal at 0 ppm(relative to the external H2O reference). Decreasing temperature to 120 K resulted in the broadeningof the spectrum to 4 kHz; however, the expected fine structure of the spectrum (as the Pake doublet)
was not observed. This permits a tentative conclusion that the compound under study is not a crystal
hydrate and the lattice hydrogen is highly mobile. The extremely informative is the 99Тс NMR
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spectrum of red pertechnetic acid powder (Fig.2) The spectral pattern and resonance parametersindicate that technetium has two states in the structure, none of them corresponding to the TcO4
ion.

Fig.2. Solid state Tc-99 NMR spectrum of pure red HTcO4 (solid)

The spectrum of a fine powder of red pertechnetic acid (figure) showed two signals at 1 =
+213(5) and 2 = 147(5) ppm (referenced to the external standard, a 0.1 M KTcO4 solution;
reported in part in [2]; the integrated intensity ratio was I1 : I2 = 2 : 3. Each of the signals had amultiplet structure due to first-order quadrupole interactions: the quadrupole coupling constants
were CQ(1) = ~ 0.25(1) and CQ(2) = 0.43(1) MHz and the asymmetry parameter of the 99Tc EFG
tensor was  = 0 in both cases.
_____________________________________________

1.
2.

F. Poineau, P. Weck, K. German et all. Dalton Trans., 2010, 39 (37), pp. 8616.
G.Kirakosyan, K.German, V.Tarasov, M. Grigoriev. 3-d Russian-Japanese Seminar on Technetium, Book of
Synopses, (2002) pp. 49-51.

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1.P11.
NEW COMPOUNDS BASED ON THE CLUSTER ANIONS [Re4Q4(CN)12]4(Q=S, Se, Te) AND CATIONS (1,10-phenH) +, Nd3+, Er3+
I.M. Gayfulin, Yu.V. Mironov, A.I. Smolentsev
Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk
yuri@niic.nsc.ru

Coordination polymers of rhenium tetrahedral cluster cyanides where Q is either sulphur,selenium or tellurium, have been intensively investigated in the past decade. The strong covalent
Re–C≡N–M interactions have allowed numerous polymeric coordination compounds to be obtainedwith transition, post-transition metals and lanthanides.
High coordination numbers inherent to the lanthanide(III) ions lead to many structuralvariations in resulting compounds. The type of structure depends mainly on the number of cyanogroups of the cluster anion involved in interaction with lanthanide cations.
In this work we present five new compounds based on the anions [Re4Q4(CN)12]4- (Q=S, Se,
Te). Three of them adopt ionic structrure, while two others are polymeric. Slow evaporation ofacidic water solutions of K4[Re4Q4(CN)12] (Q=S, Se, Te) and ten-fold excess of 1,10phenanthroline results in ionic compounds of composition (1,10-phenH)4[Re4Q4(CN)12]·nH2O(Q=S, Se, n=6; Q=Te, n=8). In case these solutions were mixed with LnCl 3 (Ln=Nd, Er) withoutacid,
amorphousbrown
precipitatehas
dropped.
Polymericcompounds[Ln(OH)(phen)(H2O)2][Ln(OH)(phen)(H2O)3][Re4Q4(CN)12] (Q=Se, Te) were crystallized byheating of this precipitates in a sealed glass ampoules in a mother solution.
In the structures of ionic compounds the 1,10-phenanthroline cations, phenH+, are packed in
an infinite stakes. Shortest distances between aromatic rings are about 3,3 Å, that is a typical value
for π-π stacking interactions. All structural units, phenH+ cations, [Re4Q4(CN)12]4- anions andcrystallization water molecules, are involved in the system of hydrogen bonds.
Structures of polymeric compounds consist of endless chains, in which every cluster anion[Re4Q4(CN)12]4- gives three cyano groups for bonding interactions with lanthanide atoms. The fullcoordination environment of lanthanide atoms also includes phenanthroline molecule, watermolecules and two OH- groups. These OH- groups bridge two lanthanide atoms into dimers with the
distance among Ln atoms of about 3.7 Å. The polymeric chains are linked together by hydrogenbonds between coordinated water molecules and cyano groups.
All compounds have been characterized by different physico-chemical methods.

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1.P12.
MUTUAL SUBSTITUTION OF LIGANDSIN COMPLEX COMPOUNDS OF RHENIUM (V)
A.A. Aminjonov
Tajik National University, Dushanbe. azimjon51@mail.ru

Since the discovery of a prominent Swiss scientist Alfred Werner coordination theory has
passed 118 years. During this period, scientists synthesized a huge number of complex compounds
and the mechanism of their formation. Proved the prevalence of complex in nature and identified
areas for their practical use. It is difficult to call the field of industry, medicine, catalysis, which are
not used to coordination compounds. However, the problem of mutual substitution of coordinatedligands in the inner sphere of complex compounds remains one of the most important problems ofmodern coordination chemistry. It is worth recalling that in 1961, AM Butlerov was proposed the
problem of mutual influence of atoms in a molecule, which was developed prominent Russianscientist VV Markovnikov. In the works Chugaeva LA and Kiltynovich SS were marked by the
influence of inner-sphere ligand facts. Research conducted by other scientists showed that the Transpattern can be extended to the chemistry of complex compounds of Pt (IV), Co (III), Rh (III) and Ir(III). Tsisinfluance of ammonia molecule on the rate of substitution of the adjacent ligands havebeen firmly established in 1957, Greenberg A. Kukushkin and Yu. N. They showed that the rate of
substitution of chloride - ion to ammonia in tetrachloroplatinate (II) Potassium is smaller than in thesalt Cossa.
Now for some metals in particular the valence state of trance set series - and tsisinfluanceligands. However, the chemistry of rhenium, which is characteristic for the valence states are 9: -3, 1 to 7 focused studies of the processes of mutual substitution of coordinated ligands was conducted.
In this research we have established several types of chemical reactions in accordance with which
there are processes of mutual substitution of ligands in complexes of rhenium (V).
The first types of reactions are reactions that occur on heating the complexes in the absenceof solvent. It is shown that when heated outer-sphere complexes of general composition(AmH)2[ReOCl5], where Am - ammonia, quinoline, methylquinoline, dimetilhinolin, is replacing
inner-outer-ligands. In reactions of this type of proton transfer occurs on the inner-sphere chloride
ligand. Another type of solid-phase transformations of complexes of rhenium (V) is that the oxygen
ligand complex as a result of the dimerization takes the place of another ligand.
2[ReO (DMSO) 2 Вr3]2H2О

[Re2O3 (DMSO)2 Вr4]+ 2DMSO + 3H2О +2НВr.

t

The process of thermal decomposition of complexes of general composition [ReO (OH)
(TP) (S), T2], where T is Cl, Br, S-DMF, DMSO, SN3SN, Hin, Py describes the general reaction[ReO(OH)(TP)(S)Г2][Re2O3(  -ТР)2Г4] + 2S+ H2Ot

The second types of reactions are reactions that occur in the solution of the following generalscheme:

Cl
H2

O
Cl

Re
Cl

Cl

Cl

Cl
+ L -HCl

H

O
Cl+ L -HCl

Re
Cl

L

Cl

Cl

O
L

Re

H
Cl

L

Cl

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Under this scheme, we have synthesized a large number of complexes of rhenium (V) with sulfurcontaining ligands azole series.
The third types established by our reactions are those reactions that are influenced by environmentand rhenium (V) in the initial complex of H2 ReOCl5 under the influence of ligands is oxidized torhenium (VII) to form ion ReO-4. For example:
H2  ReOCl5  + DMSO + 2H2O = HReO4 + DMSO + 5 HCl
The reaction of HBr in the medium flows through the circuit
H2 ReOBr5 +2 DMSO + 2H2O = [ReO (DMSO) 2Br3]2H2O +2 HBr
The fourth type of reaction are those reactions in which one replaces the other atsidoligand
atsidoliganda and labiliziruet atsidoligand being in trance - the situation to him, then the organic
ligand interacts with the complex formed.
By the fifth type of reaction include the reaction of solvatokomplexes. For example:[ReOL2G3] + S = [ReOL2G2S] F; [ReOL4 (H2O)] G 3 + S = [ReOL4S] G3H2O.
By the sixth type of reaction are reactions occurring in the interaction of ammonia with solid
complexes of rhenium (V) that is at the interface:a) Reactions which take place only with the displacement of halide ions from the inner spherecomplexes;b) The dimerization reaction of monomeric complexes with the replacement of halide ligands;a) Reaction, which resulted in the coordinated thiocyanate ions are converted into tioamidinovgroup.
By the seventh type reactions are reactions in the environment of acetone resulting in thecoordinated thiocyanate ions are converted into group’s tioamidinovye
By the eighth type of reaction are the processes of interaction with the acids of rhenium complexes
amminocontain (V).
By the ninth type of reaction include the reaction of the starting compounds such as H2[ReOG5]
with two displays (double displays) complexes of rhenium (V) resulting in the formationmonosubstituted complexes.
Thus, through focused research on the process of mutual substitution of ligands in complex
compounds of rhenium (V) we propose the following series of mutual substitution legandov: LP(Ph) 3> SCN-> Cl-, Br-> S> H2O, where L tioamidnoe-connection, S-DMF, DMSO, Py, Xin,
CH3CN.
Definition of standard redox potentials of 1,2,4-triazoltiola and some of its alkyl derivatives allowed
to determine the next number in the changing values of real potentials, depending on the positionand number of radicals in the molecule 1,2,4 - triazoltiol - 5 at 298K: 3-CH3-1 ,2,4-tthiol (209 mV)<3-Et (211.5 mV) <3-Et-4-Met (261 mV) <1,2,4-tthiol (266 mV) < 3,4 - Dimet (276,9 mV) <4-Met(320,5 mV) <3Et-4Ph (323,4 mV).
Donor properties, if reducing properties triazoltiols in this series increases. This confirms theincrease in Trans - activity of these compounds with a decrease in E0.

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1.P13.
RHENIUM AND ITS POSITION IN THE PERIODIC TABLE
Fathi Habashi
Department of Mining, Metallurgical, and Materials Engineering
Laval University, Quebec City, Canada G1V 0A6

The discovery of rhenium by Ida Noddack et al. in 1925 was a result of an intensive
study of the Periodic Table.
The search for the missing elements which were predicted by Dimitri Mendeleev
between 1869 and 1891 was intensive especially when the prediction came true after the
discovery of gallium, scandium, and germanium between 1875 and 1886.
Ida Noddack's scientific career centered around her intensive study of the Periodic
Table. This resulted in two major discoveries.
The first was based on her realization that the missing element dvi-manganese shouldhave properties similar to its neighbours in the horizontal period of the Periodic Table andnot to members of the vertical group of which manganese was the only member known. In
this way she was able to look for and discover the metal rhenium.
Thus Noddack introduced the concept of a horizontal similarity for the elements titanium
to manganese while the vertical similarities still existed but only for Zr – Hf, Nb – Ta, andMo – W below this horizontal group.
The second discovery was a daring hypothesis that the so-called element 93, a transuranium element that was supposedly formed by bombarding uranium (element 92) byneutrons, and was put under rhenium in the manganese group (in the old Periodic Table)
was not correct. Instead, she suggested that the uranium atom might have split into two
fragments - a phenomenon that later became known as fission.

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1.P14.
MACROCYCLIC RECEPTORS FOR PERTECHNETATE AND
PERRHENATE ANIONS
G.V. Kolesnikova, V.N. Khrustaleva, K.E. Germanb, I.G. Tananaevb, G.A. Kirakosyanb andE.A. Katayevc
aNesmeyanov Institute of Organoelement Compounds, Russian Anademy of Sciences Vavilov st., 28, Moscow,
119071, Russian Federationb
Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of Sciences, Leninskiy pr. 31,
119071, Moscow, Russian FederationcInstitut für Organische Chemie, Universität Regensburg, 93040 Regensburg, Germany,
email: evgeny.katayev@chemie.uni-r.de

The design and synthesis of receptors capable of selective recognition of MO4− (M = Re,
99Tc) are of great interest because they can greatly benefit the development of efficient extractants,
sensors and materials for these anions as well as new approaches for labeling of organic compounds
without any reduction step of Re(VII) and Tc(VII). Neutral receptors are known to be promising inthe sense of high binding selectivity for target anions.
The neutral macrocyclic dipyrromethane based hosts capable of MO4− (M = Re, 99Tc)
recognition were synthesized. When in protonatedform, 1 binds perrhenate with strong H-bonds frompyrrole and imine NH's, weak – from amide NH's andbenzene CH's, according to the X-ray analysis. The Hbond network of 2 is similar to that of [1H2]2+, and thecoordination mode of 2 with ReO4− was found to beequal, according to the DFT studies. The
nonprotonated form of 1 binds to ReO4− using only
pyrrole NH's, amide NH's and benzene CH's,
according to the DFT studies.
Affinities of the receptors towards both MO4−
(M = Re, 99Tc) were acquired by direct UV-vis
titrations and towards 99TcO4− specifically by reverse99
Tc NMR titration. Binding constants were found to
be one of the largest known to date (KMO4 ≈ 103-105 M-1). Receptors possess selectivity towards
target anions.
We gratefully acknowledge Russian Academy of Sciences program “Chemistry and PhysicoChemistry of Supramolecular Systems and Atomic Clusters”.

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Tc in the Nuclear Fuel Cycle and in the Environment.
Analytical Chemistry of Tc and Re

The chairmen of the Second section of ISTR2011 in view of the
Presidium of Russian Academy of Sciences

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2.1.
HOW TO MANAGE TECHNETIUM (NUCLEAR RARE METAL) AND
ACTINIDES, TOWARD FUTURE REPROCESSING SYSTEM PROVIDED
BY PROLIFERATION RESISTANCE
M.Ozawa, T.Suzuki, S.Koyama, H.Sagara and M.Saito

Tokyo Institute of Technology, Research Laboratory for Nuclear Reactors, 2-12-1 N-21, Ookayama, Meguro-ku,Tokyo,152-8550, Japan

Keywords: Nuclear rare metals, Cycle strategy, Separation, Transmutation and Utilization(S&,T,U) , Proliferation resistance
Abstract:
Aiming at utilization of elements / nuclides in spent fuel (i.e., nuclear rare metals (NRM) including
Tc ) and minimization of long-term risks of radioactive wastes as well, a new fuel cycle concept has
been progressed during the phase-I period (FY2005-2010). The strategy is based on a Trinitarian
research as such separation, transmutation and utilizaiton (S&T,U), especially relied upon advanced
radiochemical separation technologies. A catalytic electrolytic extraction (CEE), utilizing underpotential deposition (UPD) by Pdadatom/Rhadatom, is advantageous for separation and utilization(and/or stockpile) of light platinum group metals (PGM), Tc and Re. Their co-deposits have been
showed highly catalytic ability for electrolytic production of hydrogen. Tertiary pyridine resin(TPR) will not only strongly adsorb PGM, Tc and Re, but also perfectively separate spent fuel into
the groups of U/Pu/Np, Am, Cm and lanthanides (Ln), etc. Owing to MA (237Np, 241Am) recycling
into nuclear fuel, proliferation resistance of Pu would be strengthen by their neutron capture
reactions to 238Pu and 242Pu.
The new fuel cycle strategy will conclude, some fission products like Tc, Mo, PGM, Lns and Tc
must be separated and utilized as resources or alternatives. On the other hand, MA and even longlived radioactive Lns such as Sm, Eu, etc, should be recycled and dopted to enhance proliferation
resistance of Pu. Nuclear fission reaction must be utilized multidirectionally.

Weight (g/tHM)

Introduction (Nuclear Rare Metals, “Kopernikanische Wendung“)Fission reaction of 235U will generate more than 40 elements and 400 nuclides in the spent fuel.
Among them, 31 elements are categorized as rare
metals (NRM ; Nuclear Rare Metal), and some are
1.0E+05
Mo-100(S)highly enriched in the spent fuel. Typical yields for
Mo-98(S)such noticeable NRM as Pd, Ru, Rh (light PGM)
Mo-95(S)
Mo-97(S)
1.0E+03and Tc, La, Nd (light Ln) will reach to more than
Mo-96(S)
3kg to ca.10kg per metric ton of the reference FBR
1.0E+01
spent fuel (150GWd/t, cooled 5 years). By a close
investigation, individual＂exit strategy＂can be
1.0E-01
individually proposed toward their utirization /recycling[1]. Namely,i) Use as elements; Low radio-toxicity 99Tc (e.g.,
exemption Level≧104Bq/g) shuold be used as
catalyst as the same as Re, or irs alternative material.

1.0E-03
1.0E+00(cooled 6 years)

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

Time after separation (year)

Fig.1 Isotopic abundance of FP Mo
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Hydrogen overpotential (η) of metals are
periodically chaged as their d-electron orbital
characteristics. Althoughηdata on Tc is very
limited,ηTc in the acidic solution seem to be thefollowing[2];Pt (ca.0 mV)≦Ru, Rh, Pd <Re≦Tc <Ni(ca.300 mV) <Ti
Ni electrode is currently available forcommercial hydrogen production in alkali
solution. ηTc is lower thanηNi by ca.100mV.
Ru and Rh can be used after the stockpile at
Fig.2 Isotopic abundance of FP 99Tc
least 40 years and 80 years, respectively, to belower than their exemption; i.e., BSS level of106
Ru and NRPB level of 102Rh. Pd is approximately the same radiotoxicity as Tc
107( Pd:105Bq/g(NRPB)). Notably, natural isotopic abundance of Mo(%) are 92Mo:14.8, 94Mo:9.25,
95
Mo:15.9, 96Mo:16.6, 97Mo:9.5, 98Mo24.1 and 100Mo:9.63. Thus, higher order isotopic abundanceof FBR Mo, as shown in Fig.1, will be beneficial for production of 99Mo. Very low radioactive Dy,
La and Nd seem to be highly strategic and become important resource in the forefront industries.
ii) Use as nuclear fuel; Doping of 237Np, 241Am and Cm to enhance proliferation resistance of Pu as
discussed in section 3. Doping radioactive Lns like Pm, Sm, Eu, etc may also conribute to increase
ploliferation resistances of Pu.
iii) Use as radiochemicals; 137Cs as radiation source of γ alternatiing to 60Co), and 90Sr, 238Pu,
241
Am and 242,244Cm as heat sources.
iv) Use as commerce of high expence stable RI; During long-term stockpile of 99Tc, decay product99
Ru (stable) will gradually increased as shown in Fig.2. While stable 100Ru can also be obtained bytransmutation of 99Tc, pure 99Ru isotope (very expensive 39,040$/g) would be obtained without ofany transmutation processing.
Fuel cycle strategy and hydrometallurgical chemistry toward utilization
Toward simultaneous realizationof utilization of elements /nuclidesandultimate
minimization of the ecologicalrisks, a new fuel cycle paradigm isnecessary to be built. Hence,Adv.-ORIENT(Advanced
Optimization
by
Recycling
Instructive
Elements)
Cycle
strategy is set under the following
tactics[3]. 1/ Higher purity on
NRM for utilization, allowing
lower DF on actinides just forburning in FBR. 2/ To reduce thesecondary rad. wastes; adopt softhydrometallurgical, but non-SX
separation process, with salt-freereagents. 3/ Deep separation of all

Fig.3 New fuel cycle concept based on S&T,U
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actinides into 3-4 groups, U, Pu/U/Np, Am and Cm, directly from the spent fuel by IXC method.
Eventually, pure Lns can be recovered. 4/ To sharpen the separability, hydrochloric acid (HCl)media is allowed in combination with nitric acid (HNO3) media. As shown the concept in Fig.3, themost significant policy change is that NRM shall be no longer wastes but main product along withactinides in the fuel cycle. In the point of back-end chemistry, precedent separation of some of
NRM is preferable because some will disturb decontamination of actinides in the reprocessing andthe vitrification of HLLW as well. A period to reduce the radio-toxicity below the level equivalent
to 60 ton of natural uranium is one of the indexes on environmental impact of reposited 1 ton of
HLLW. In adv.-ORIENT Cycle, by putting the separation factors of 99.9% for all An, 99% for
137
Cs, 90Sr and the other NRM, and 90% for RE, such a period can be dramatically reduced toaround 1×102 years.
Catalytic electrolytic extraction (CEE), utilizing under potential deposition (UPD) with forming of
undissolvable metal solid solution in acidic media, can effectively separate Ru ,Tc and Re (Tcsimulator) from either HNO3 or HCl solution. Pd and Rh themselves were easy to be deposited. In
dilute HCl media, such CEE occurred more distinctively than in dilute HNO3 media. For instance,in the four NRM metal ions mixture solution (corresponded to FBR spent fuel composition),
observed deposition yields were typically in the following order; Pd, Rh (>99%) > Re (91%)) > Ru(85%) > Tc (69%). During the CEE, Pd or Rh might act as promoter at the surface of electrode (i.e.,
Pdadatom, Rhadatom) and mediator in the bulk solution (i.e., redox ion pair).
Tertiary pyridine resin (TPR), composing a nitrogen atom in six-membered ring, is characterized tosimultaneously have two functions as weakly basic anion-exchanger and soft donor ligand. It willshow high thermochemical and radiochemical stabilities especially in HCl media. An original ideaof combinatory use of conc.HCl and conc.HNO3 media was based on such facts that recognition ofsofter ions like Am3+ and Cm3+ (5-f elements) was clearer than Ln3+ (4-f elements) in HCl media,
and in HNO3 media the distribution depended just on the difference of ionic radius independently
either 4-f or 5-f elements. Extractabilities of both Am3+ and Cm3+ improved by enhancing
complexation of protonated pyridine with anions due to the dehydration brought by co-existingmethanol, and thereby increasing SFAm3+/Cm3+.
The CEE method is advantageous because NRM would be recovered in solid state at the electrodesurface as metal (Ru, Rh, Pd, (Tc)) and/or oxide (Tc, Re). Recovered NRM was sphere micro
deposits foamed by coagulating with nano particles in the case of Pd2+ involved CEE. Those
deposits were dense, and mechanically stable, with showing electrochemically high catalytic
reactivity on electrolytic hydrogen production. Ru has been confirmed as a dominant element for
the reactivity, while Pd played as just a ＂starter＂ nucleus and a ＂binder＂ among the involved
elements during the deposition. Higher reactivity of Tc than Re will suggest exploring new
application fields of it. Further, a new evaluation was initiated to evaluate the producibility on morevaluable PGM (e.g., Rh) by re-irradiation of FP Ru, and 99mTc by FP Mo, both separated from thespent fuel. For this purpose, parametric studies are necessary to optimize, fuel and reactor types,
fabrication and irradiation conditions, etc.
Enhancement of proliferation resistance of Pu by MA and Ln recycling
Proliferation resistance of Pu will be enhanced by increasing of even mass number of actinides of
238
Pu, 242Pu and 242Cm, etc. 238Pu and 242Pu, characterized specifically by high decay heat tofabricate weapon difficult, are high spontaneous fission neutron source to deteriorate the quality of
the Pu toward nuclear explosion [4]. Therefore, those become “isotopic barrier” against
proliferation. Such 238Pu will be generated in the reactors by the following neutron capture reactionsof MA,
241

Am(n,γ)242Am→β(18h)→242Cm→α(162.8d)→238Pu,
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237

Np(n,γ)238Np→β(2.0d)→238Pu.

Sagara, et al reported the irradiation results of pure 241Am oxide sample in the experimental fast
reactor “Joyo”. Under the neutron fluence conditions ( x1022[n/cm2]) like core: 8.15, Ax.-ref: 2.48
and Rd.-ref: 4.18, neutron capture ratio was 65% (for generating Pu and Cm) and fission ratio was
28% at the center of core with harder neutron spectrum [5]. However, at the reflector region neutron
capture reaction increased to be more than 80% with decreasing fission reaction, conversely.
Relative isotopic abundance of 238Pu plus 242Pu was more than 98% in the both case, and that of242
Cm was more than 97%, where the transmutation ratio of Pu/Am was less than 7% and 2% for
Cm/Am. Evidently, transmutation of 241Am was successfully achieved, and the isotopic ratios of238
Pu and 242Pu were increased. When MA doping is 2% against DU, the ratio of 238Pu plus 242Pu
will be more than 10%, and that will satisfy both criteria on 238Pu content, e,g., 9% [6] andattractiveness factor calculated as 6% [4].
Separation of pure MA and PGM from the spent fuel was successfully demonstrated [7] utilizing
previously described IXC separation scheme [8]. Irradiated MOX fuel (143.8GWd/t) at the fast
experimental reactor “Joyo” was dedicated for the experiment. As experimental results, therecovery ratio of 241Am was more than 95 % whole through the processes, and the impurities of241
Am product against Ln (144Ce+154Eu) , 243Cm and γFP (106Ru+125Sb+137Cs) were very low, lessthan 0.3ppm, 1 ppm and 1.8ppm, respectively. The separation degree on 243Cm from 241Am productwas more than 2.2x103. Possibly, TPR chromatography method will meet well with the MA (241Am)
recycling in the points of increasing proliferation resistance as well as decreasing environmental
burden. Further study will focus on clarifying Np behavior, preferably controlling its behavior
together with Pu. Intra-group separation of Ln and PGM (including Tc), and engineering feasibility
and simplification in HCl / HNO3 hybrid media is issue in the phase II.
Conclusion
Aiming at utilization of elements / nuclides of rad.wastes, a new fuel cycle concept has been
progressed. The strategy is based on a Trinitarian research as such separation, transmutation andutilizaiton, especially relied upon advanced radiochemical separation technologies like ion
exchange and electrochemistry by a conbinatorial mannner. A catalytic electrolytic extraction
method, utilizing under potential deposition by Pdadatom/Rhadatom, is advantageous for separation andutilization (or stockpile) of light platinum group metals and Tc. Tertiary pyridine resin will not only
strongly adsorb Tc and Re but also generate co-products of U/Pu/Np, Am, Cm and Ln, thereby
sufficiently strengthen the proliferation resistant character (increase 238Pu content) of recycled Pu isachieved. The separation senario of all of actinides and fission products in the spent fuel should be
strategically re-developed to satisfy the various requirements.
Condolence: During preparing this manuscript, the most powerful, magnitude 9.0 earthquake andtsunami attacked Tohoku-Kanto pacific region on Friday March 11, 2011. These caused a great
disaster on Fukushima NPPs and the situation is not settled-down yet. With the deepest sympathy
with regret, and sincere gratitude for helps by foreign countries.
References
1. M. Ozawa, Separation and Utilization of Nuclear Rare Metals and Actinides in Advanced
Reprocessing System, 香山科學會議 第389回｢核燃料再処理放射化学｣北京・香山飯店The
389th Xiangsham Science Conference Workshop of Nuclear Fuel Reprocessing, Proc.
Radiochemical Challenges in Nuclear Fuel reprocessing, pp.27-29, Xiangshan Hotel, Beijing,
China, Dec22-24, 2010.
2. H.Kita, et al., Denkikagaku, 38,17(1970)(in Japanese)
3. Masaki Ozawa, Tatsuya Suzuki, Shinichi Koyama, Hiroshi Akatsuka, Hitoshi Mimura and
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Yasuhiko Fujii, A New Back-end Cycle Strategy for Enhancing Separation, Transmutation andUtilization of Materials (Adv.-ORIENT Cycle), Progress in Nuclear Energy, 50(2008)476-482,
ELSEVIER (2008).
4. Masaki Saito, Protected Plutonium Production by Transmutation of Minor Actinides for Peaceand Sustainable Prosperity, Proc. of Global 2009, Paper 9397, Paris, France, September 6-11,2009.
5. Hiroshi Sagara, Tetsuro Yamamoto, Shinichi Koyama, Shigetaka Maeda, Tomooki Shiba and
Masaki Saito, Numerical Analysis of Irradiated Am Samples in Experimental Fast Reactor Joyo,
Actinides2009, IOP conf. Series: Materials Science and Engineering 9(2010)012006.
6. G.Kessler, et al., Nuclear eng. and design, 238(2008)3429-3444.
7. Shinichi Koyama, Masaki Ozawa, Tatsuya Suzuki and Yasuhiko Fujii Development of a Multifunctional Reprocessing Process Based on Ion-Exchange Method by Using Tertiary Pyridine-Type
Resin, Journal of Nuclear Science and Technology, Vol.43, No.6 pp.681-689 (2006).
8. Tatsuya Suzuki, Yasuhiko Fujii, Wu Yan, Hitoshi Mimura, Shinichi Koyama, Masaki Ozawa,
Adsorption Behavior of VII Group Elements on Tertiary Pyridine Resin in Hydrochloric Acid
Solution, J Radioanal Nucle Chem (2009) 282;641-644..

F. Poineau, C. Kremer, D. Suglobov, acad. B.F. Myasoedov, K.E. German at the
ISTR2011 Welcome party

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2.2.
COMBINED SEPARATION OF Pd AND Tc FROM THE RAFFINATES OF
THE SPENT NUCLEAR FUEL REPROCESSING
Т. Boytsova*, V. Korolev*, Y. Pokhitonov*, V. Babain*, М. Ozawa**, Т. Suzuki*** RPA «V.G. Khlopin Radium Institute», Saint-Petersburg, Russia, 28, 2-nd Murinsky ave., 194021. E-mail:radium@atom.nw.ru** Tokyo Institute of Technology, Tokyo, Japan, 2-12-1 O-okayama,
Meguro-ku, 152-8550. E-mail: tasuzuki@nr.titech.ac.jp

A small amount of “reactor” Pd, Ru, Rh and Tc metals is needed for investigation of thepossibility of production and use of electrodes in hydrogen energetics covered by a composite madeof these “reactor” metals. One of the sources of these metals is the raffinates of the first extraction
cycle of the spent nuclear fuel (SNF) reprocessing.
The purpose of this study was to investigate the Tc and Pd sorption behaviors, to search theagents for their desorption, to test the determined conditions of the metals separation with use ofreal SNF reprocessing solutions.
The examples of individual Pd and Tc sorption by anion exchange resin from nitric acidsolutions are well-known. However, their combined separation wasn’t mentioned earlier.
In this study the strongly basic anionite ВП-1АП, which had been previously applied toseparate a “reactor” Pd, was used as a sorbent.
Tc and Pd sorption under static and dynamic conditions were studied. It is shown that the
combined sorption should be carried out at a HNO3 concentration not more than 2 M. When passing
through the sorbent at least 50 column volumes (c.v.) of the model solution (CHNO3 = 2 M; CPd =100 mg / l; CTc = 100 mg / l) almost 100% of Pd and 30% of Tc were sorbed on the resin.
The conditions for 100% Pd and Tc separation from the feed solution were found.
The desorption with DTPA solution in the wide range of acidity allows to achieve both
combined 100% yeild of Pd and Tc in 15 c.v. and individual desorption of these metals (Pd in 8
c.v., Tc in 15 c.v. ).
An example of the combined separation of Pd and Tc from the SNF was given in the study.
Distribution of Pd and Tc by fractions of experiment solutions, factors of purification of these
metals from gamma impurities and obtained dynamic exchange capacities are shown.

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2.4.
THE ELABORATION OF TECHNOLOGY BASES FOR THE ARTIFICIALSTABLE RUTHENIUM PREPARATION FROM TECHNETIUM-99
TRANSMUTATION PRODUCTS
А.А. Kozar’1, V.F. Peretrukhin1, K.V. Rotmanov2, V.A. Tarasov2
1

Frumkin Institute of Physical Chemistry and Electrochemistry of RAS, 31/4, Leninsky prosp., Moscow, 119071
Russia, kozar@ipc.rssi.ru

2

ederal State Unitary Enterprise State Scientific Centre – Research Institute of Atomic Reactors, Dimitrovgrad 10,433510 Russia, orip@niiar.ru

The bases of technology have been elaborated for the artificial stable ruthenium preparationfrom the 99Tc transmutation products. The process includes the following steps: the isolation
technetium from spent fuel with additional purification of Tc from actinides, the manufacture oftechnetium targets, their irradiation with high flux of thermal and epithermal neutrons, the exposureof irradiated targets for the short-lived radionuclides decay, chemical separation of ruthenium fromtechnetium and the exposure of prepared ruthenium up to the fission product 106Ru decay.
The metallic targets have been prepared from technetium which contained ~5·10–8 g actinide
impurity per gram Tc. The irradiation of the targets has been carried out with thermal neutron flux
6.8·1014 – 1.14·1015 сm–2·s–1 (epithermal neutrons part is 0.06 – 0.1) during 73 – 425 eff. days andburn up has been achieved 19 – 70% (for 3 different groups of Tc targets).
The dissolution of irradiated targets has been carried out in KOH solution in presence ofexcess of KIO3 at 70 – 80°C. Volatilization of RuO4 from KTcO4 solution and other chemical
methods have been applied for the isolation of ruthenium.
Total Ru separation factor has been achieved 1012. The exposure of prepared artificial
ruthenium during 10 years needed for the diminution of the 106Ru, 106Rh radioactivity of the metal
up to the level required for its any application.
About 5 grams of stable ruthenium have been prepared in this work from 10 g of thetechnetium. This artificial ruthenium was nearly monoisotopic and contained 97.5 – 99.7% 100Ru
depending on 99Tc burn-up. The achieved 99Tc transmutation rate and targets burn-up value arerecords for today and may be increased by the rise of the epithermal component in the neutron flux.

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2.5.
TECHNETIUM CATALYTIC EFFECT AND SPECIATION IN NITRIC
ACID SOLUTIONS IN PRESENCE OF Np(V), Th(IV) and Zr(IV) AND
REDUCING NITROGEN DERIVATIVES
K.E. German, Ya.A. Obruchnikova, D.N. Tumanova, V.F. Peretrukhin, Ph. Moisy*.
IPCE RAS, Moscow, Leninskii pr.31- 4, 119071 Russia* - CEA – Marcoule, DEN DRCP, BP17171 – 30207, Bagnols sur Ceze, France

The technetium species develop the catalytic effect being of high importance for the
reprocessing of the spent nuclear fuel [1]. One would just mark that the large-scale reprocessing in
the UK was delayed by 5 years in the startup stage due to the harmful Tc-effect [2]. An important
item of Tc separation from the reprocessing solutions is the mutual effect of a number of redox
stable (Zr) and redox sensitive elements (especially Tc, see p.e. [3-6] and Np) present in thesewastes. Two technetium valence states (VII and IV) are considered to be rather stable under theconditions of spent nuclear fuel reprocessing.
In the previous report we have demonstrated the catalytic effect of Tc(VII and V) on the
reduction of Np(V) to Np(IV) with hydrazine in nitric acid resulted in Np(V) disappearance and in
the accumulation of Np(IV) different species, so that the free ionic form of Np(IV) accumulated inlower concentration, compared to decrease in Np(V) concentration. This fact indicated the possible
Np(IV) complex formation with some of the reaction product [7-8]. The Tc(VII) participation inthis reduction process was anticipated taking into account the common catalytic properties oftechnetium, while the interaction of An(IV) with Tc reduced species was difficult to predict andneeded some additional experimental study that was demonstrated in [9-10] with simulated waste
solutions with Th(IV) taken for typical example of An(IV). The existence of such species wasdifficult to predict based only on the accepted thermodynamic data [3], although the possibility of
deep Tc reduction even to Tc(II) species in nitric acid was already demonstrated in [12], and theimportance of hydrolyses and polymerization in aqueous solutions of different acids were shown in[8-11]. Anyhow such questions as the influence of the Tc valence state in the catalytic action on Np
behavior remained unclear as only Tc(V) and Tc(VII) species were tested in [7-10] and thecorresponding study of the Tc(IV) species is being undertaken in this report. Because of thepossible interference of the Tc(V and IV) and Np(V,IV) optical spectra, the procedure of spectra
analyses elaborated in the previous report was used for the optical separation of individual Tc andNp species before the kinetic treatment of the experimental data aiming the determination of thereaction orders in Np(V), Tc(IV), N2H5+, H+.
The experimental procedures was based on the conventional spectrophotometric methods forthe kinetic measurements of Np(V) and Tc(IV). For the determination of Np(V) concentrations the
NIR absorption peak at 980 nm was used. The constant initial concentrations of Np(V) andN2H5NO3 were used in all the experiments, while C0(Tc(IV)) varied as (0.24 – 1.2)*10-3 mol/l. The
temperature interval from 25 to 55oC was set-up in different sets. Tc(IV) concentrations were
measured at the 400 nm (after the Np(IV) spectra contribution corrections), while Tc(V) was
determined according to the development of the shoulder at 470-500 nm with similar corrections for
Np and Tc(IV).
In the present work the Tc was initially reduced to Tc(IV) previous to addition to the test
solutions. In such a case no induction period was needed for the Np(V) reduction reaction similar to
the Tc(V) effect, studied before [8]. Similar to the previous report, the deconvolution analysis of
the spectra was critical for the understanding of the chemical reactions in the system underconsideration. While the Tc(VII) spectrum is well known and completely characterized, somemisunderstanding exists for Tc(IV), Tc(III) and Tc(V) in acidic solutions. We consider the mostreliable for spectroscopic standard purpose to use Tc(IV) spectrum registered after dissolution of
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TcO2 *nH2O in sulfuric acid under argon atmosphere. Utilization of these spectra as a standard was
fruitful in the previous work for the Tc – Np spectra deconvolution. It is important and possible
because the spectroscopic parameters have been determined in separate tests.
Anyhow the Tc(IV) stock solution for the kinetic tests was each time freshly prepared by
reduction of 10-2 M Tc in 1.5M nitric acid with excess of hydrazine nitrate. The following dilutionof the aliquots in test solution influenced only the Tc concentration.

Fig.1. Typical view of Np(V) reduction withhydrazine catalyzed with Tc(IV)([Tc(IV)]=1.02*10-5M, [HNO3]=1,6 M).

Fig.2. Deconvolution of typical mixed spectrum of Tc(IV) –Tc(V)-Np(IV) solution

The mixed Tc(IV) –Tc(V)-Np spectra could be subtracted one from another as shown at theFig. 6-3, where the presence of at least three different Tc species can be seen from thedeconvolution analyses.
At least one of the intermediate Tc species has unknown molar extinction coefficient
therefore the quantification of the Tc valences was impossible in this solution system by optical
spectra measurements. Anyhow we can estimate from the subtracted spectra that the initial Tc(IV)is partially oxidized in course of the catalytic process and the total reduction of Np(V) to Np(IV) is
run with a mixture of Tc (IV) and Tc(V) species stabilized in the nitric acid solution in presence of
hydrazine.

Fig. 3. The typical evolution of the Np(V) spectrumin “Np-region” (980 nm) in the course of Np
reduction with hydrazinium, catalized by Tc(IV).

Fig. 4. Np(V) reduction with 0.052 M H2N5NO3
catalyzed by Tc(IV) (0.98*10-4 M) in 1.51, 1.95,
2.52, 3.01 and 3,51 M nitric acid.

The registration of the spectra evolution in “Np-region” (980 nm) gave evidence that thechange in the absorption at 980 nm is completely due to Np(V) reduction to Np(IV) (Fig. 3). In the
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tests with the previously prepared Tc(IV) being added to the solution as a catalyst for Np(V) to
Np(IV) reduction with N2H5+ in 1.5 M HNO3, the Tc spectrum underwent just very smalltransformations while the peak Np(V) (Fig.3) decreased with time. When this previously
synthesized Tc(IV) compound dropped into the Np(V)-hydrazinium- x*HNO3 solutions withdifferent acidities no induction period was observed at 36 oC (Fig. 4) as well as at othertemperatures up to 55 oC.
The Np(V) to Np(IV) half-reduction time for this reaction increased from 5 to 25 min while
the acidity of the solutions was decreasing from 3.51 to 1,52 M HNO3. The kinetics was practicallylinear within the 0.8 conversion factor thus indicating the zero order in [Np] for this reaction in thisacidity region (1.5-3.5 M).
The reaction rate constants are tabulated in the Tab.1.
Table 1. KoI for Np(V) reduction with hydrazine Table 2. The temperature dependence of the reaction
catalyzed by Tc(IV) at different C(HNO3).
rate constant KoI for Np(V) reduction catalized withTc(IV).

[HNO3],
M
1,51

KoI , *104
mol/l*min0,29lg[HNO3]

lg KoI

T,
o
C

1/T,
1/K

KoI , *104
mol/l*minlg KoI

0,179-0,53820

0,003410,4-0,398

1,95

0,49

0,290

-0,31025

0,003360,6-0,222

2,52

0,84

0,401

-0,076

3,01

1,19

30

0,003300,8-0,0969

0,479

0,075

3,51

1,61

0,545

0,206

35

0,00325

1,3

0,114

40

0,00320

1,9

0,279

45

0,00314

3,1

0,491

50

0,00310

4,4

0,643

Fig. 5. Reaction order determination from
LgKo=f(Lg(CHNO3)

Fig. 6. Reaction rate constant KoI as a function of
aHNO3

The Np(V) reduction reaction order was determined from lg K oI = f(Lg(CHNO3)), thedependence corresponds to the second order of the reaction kinetics (Fig. 5.) . The correction of thedata for the activity of H+ in nitric acid gave similar dependence for the KoI (Fig. 6).
The temperature dependence of the reaction rate constant was determined at thetemperatures of 20 – 50 oC (Tab.2, Fig.7).
The resulting activation energy was estimated as 41,9 (3) J/M.
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Fig. 7. Reaction rate constant Ko I as a function of inverse temperature (for 20 – 50 oC temperatureinterval).

The effect of technetium(IV) ions concentration on the catalytic Np(V) reduction with hydrazine
was tested in the set of solutions prepared based on 2.84 M HNO3. This acidity was used as it iswell known [4] that the fraction of the hydrolyzed form of Tc(IV) could be important in thesolutions with smaller acidity thus leading to its smaller catalytic activity.
KoI 3,5
M/L*min
3
2,5
2
1,5
1
0,5
0
0,5

1

1,5

2

2,5

[Tc(IV)], M*104

Fig. 8. Np(V) reduction with 0.052 M H2N5NO3
catalyzed by Tc(IV) added at different
concentration: (0.8, 1.0, 1.25, 1.5, 1.75, 2.0 *10-4M) in 2.84 M nitric acid.

Fig.9. Effective reaction constant KoI for Np(V)reduction with 0.052 M H2N5NO3 catalyzed by Tc(IV)as a function of different Tc concentration (0.8, 1.0,
1.25, 1.5, 1.75, 2.0 *10-4 M) in 2.84 M nitric acid.

C(N2H5NO3) 0.3 M

D(480 nm)

0,075

C(HNO3) 1.7 M

0,050

C(Tc) 1,2 mM
C(Tc) 0,9 mM
C(Tc) 0,6 mM

0,025

0,000
20

30

40

50

60

time, minFig. 10. Lg KoI as a function of different Lg([Tc])(for [Tc(IV)init]= 0.8, 1.0, 1.25, 1.5, 1.75, 2.0 *10-4M) in 2.84 M nitric acid.

Fig.11. The evolution in the spectra optical density
50oC for different total Tc concentrations.

As follows from Fig 10, the reaction order for Np(V) reduction with H2N5NO3 catalyzed byTc(IV) over [Tc] is equal to 1. After the reduction of Np(V) to Np(IV) is complete the evolution in
species concentration ratio during the first hour of storage even at 50oC (Fig. 11).
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So, the kinetics equations for the Np(V) reduction with H2N5NO3 catalyzed by Tc(IV) could be
drawn as:- (d[Np(V)]/ dt = Ko[Tc(IV)]*[HNO3]2 ,where Ko = KoI / ([Tc]*[HNO3]2 = 14.8 (2) *10-2 M-2*min-1
It is important to note that in this report the effect of nitric acid on the KoI(Np(V)) was notdevided foe the separate effects of [H+] and [NO3-] although we may predict from the known
chemical properties of Np(V) that the latter dependence should be of higher importance. This study
was not the special task of this report but it is under way and will be completed in the nearest
future.
An important item of the Np(V) catalytic reduction driven with Tc(IV) is the hydrazine
concentration. The reduction of Tc(V) to Tc(IV) in high excess of hydrazine is a comparatively fast
reaction.
When the reduction of Np(V) is complete, the latter is stable for 0,5-1,5 hours depending on
the temperature of the solution. The further reduction of Tc (probably to Tc(III) causes thehydrazine catalytic decomposition and then – partial back oxidation of Np(IV). For longer terms theconsiderable fraction of Tc is oxidized back to Tc(VII) that was confirmed by liquid – liquid
extraction tests and the EXAFS spectra registered on the aged solutions.
When Tc(VII) is added to the Np(V) solution containing hydrazine, the induction period isneeded for the startup of Np(V) catalytic reduction. In case when Tc(V) was added no induction
stage is observed. The previously prepared Tc(IV) being added to Np(V) in 1.5- 3.5 M nitric acid –hydrazine nitrate solutions) causes the Np(V) catalytic reduction with hydrazinium to Np(IV)without any induction period. The Np(V) reduction with N2H5+ is catalyzed by Tc(IV) ions andfollows the kinetics being zero order in [Np(V)], 1-st order in [Tc(IV)], 2-nd order in [HNO3], withactiv = 41.9(3) J/M.
When the reduction of Np(V) is complete, the latter is stable for 0,5-1,5 hours depending on
the temperature of the solution. The further reduction of Tc (probably to Tc(III) causes thehydrazine catalytic decomposition and then – partial back oxidation of Np(IV).
The technetium reduction by hydrazine nitrate and hydroxylamine chloride in the presenceof Th(IV) and Zr(IV) was investigated. The experimental procedures of this work involved
conventional spectrophotometric methods for the kinetics measurements of Tc. The initialconcentration of Tc was varied as 0,4 – 1,52 mmol/l, C(Th) = 0 – 6,32 mmol/l, C(N2H5NO3) =0,255 M. The temperature was about 550C. The reactions were carried out in thermostatic quartz
cells. A typical sequence of spectral changes in one experiment is given at Fig. 12. To get theequilibrium state more than 2 hours were needed. As can be seen the reaction consists of 3 stages.
On addition of hydrazine to Tc-Th solution in nitric acid the reaction first proceeds as a Tc(VII)
reduction to Tc(IV) thus developing the shoulder at 400 nm and following the zero order kinetics,
initiating the hydrazine decomposition with gas evolution, then decomposition of Tc(IV) takes
place in similar zero order kinetics with formation of unidentified Tc(X) species, then finallyforming pink or brown (depending on Tc concentration) Tc(Y)-Th(IV) complex characterized witha peak at 470-475 nm in first order kinetics. The later is supposed to be Tc(V)-Th(IV) complex
which is stable for several days at 550C.
D=f(WL)
Tc(IV) decomposition

C(Tc)=1,14 mmol
C(Th)=3,32 mmol
C(HNO3)=1,5M
C(N2H5NO3)=0,255M
t=55oC

425

475

525

575

WL, nm

625

675

725

0,1
0,09
0,08
0,07
0,06
0,05
0,04
0,03
0,02
0,01
0
375

D=f(WL)
Tc(V) formation
0,09

C(Tc)=1,14 mmol
C(Th)=3,32 mmol
C(HNO3)=1,5M
C(N2H5NO3)=0,255M
t=55oC

0,06

C(Tc)=1,14 mmol
C(Th)=3,32 mmol
C(HNO3)=1,5M
C(N2H5NO3)=0,255M

0,05

t=55oC

0,08
0,07

D

0,1
0,09
0,08
0,07
0,06
0,05
0,04
0,03
0,02
0,01
0
375

D

D

D=f(WL)
Tc(IV) formation 400 nm

0,04
0,03
0,02
0,01

425

475

525

575

625

675

725

0
375

WL, nm

425

475

525

575

625

675

725

WL, nmFig. 12. Reduction of Tc with hydrazine in presence of Th
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The conditions providing intermediate Tc species stabilization in presence of four valence
actinides were found giving an evidence that at least three reduced Tc species (Tc(IV), TcX and
Tc(V)) are appearing and disappearing in the course of the consequent reactions (Fig. 13). Two
different technetium species exist simultaneously. The reaction of Tc(V) complex formation inpresence of Th(IV) can be turned back to Tc(IV) formation when a new portion of hydrazine is
added.
Dmax=f(C(Tc)) at 470 nm

100
90

Tc(IV)

80
70

Tc(VII)

60

% 50

Tc(X)

40
30

Tc(Y)

20
10
0
0

6

12

18

24

30

36

42

48

54

60

66

72

time, minFig. 13. Change in content of reduced Tc species.

0,6

C(Zr)=6,64 mmol/l

0,50,4Dmax 0,3

0,2
0,1
0
0

2

4

6

8

10

12

14

16

18

20

С(Tc), mmol/l

Fig. 14. D=f(c(Tc)) for equilibrated solutions in presenceof Zr(IV).

It was found that the final complex of Tc with Th (Zr) at 470 nm by hydrazine and at 500
nm by hydroxylamine reduction has the ratio of two to one accordingly (Fig. 14).
It was found that Th and Zr produce clear stabilizing effect onto several reduced Tc species.
Tc(V) forms stable complexes with redox inactive d- and f-elements like Th(IV) and Zr(IV) in
nitric acid in presence of reducing N-derivatives (with the ratio between Tc and Zr is 2 to 1.
References
1. Campbell D.O., Burch W.D. The chemistry of fuel reprocessing: present practices, future trends.
J. Radioanal. Nucl. Chem., Art., 1990, v.142, No. 1, p.303 - 320.
2. Phillips C. Uranium - plutonium partiotionning by pulsed column in the first cycle of thethree cycle thermal oxide reprocessing plant. Waste'92, Proceedings (1992) 1041- 1045.
3. J. A. Rard, M. H. Rand, G. Anderegg, H.Wanner. Chemical thermodynamics 3. Chemical
Thermodynamics of Technetium. Edited by M.C.A. Sandino and E. Östhols, OECD NEA Data Bank. 1999, Elsevier Pbl.
4. V.S.Koltunov, R.J.Taylor, T.V.Gomonova, O.A.Savilova, G.I.Zhuravleva, I.S.Denniss //Radiochim. Acta 88, 425-430 (2000).
5. N.Boukis, B.Kannellakopulos // Radiochimica Acta 49. 141-145, (1990).
6. Zelvert A.: Rapport CEA-R-5443, (1988).
7. D.N.Tumanova, K. E. German, Ph. Moisy, M. Lecomte, V. F. Peretrukhin. In: Abstracts of the
6-th International Symposium on Technetium and Rhenium – Sciences and Utilization. NMMU
- Port Elizabeth, 7-10 October 2008, p.46.
8. K. E. German, Ya. A. Obruchnikova, Ph Moisy , M. Lecomte, V. F. Peretrukhin. In: 6-th
International Symposium on Technetium and Rhenium. NMMU-Port Elizabeth, 7-10 October
2008, p.29.
9. K.E.German. The Fourth Adv.-ORIENT Cycle Seminar. “New Resource Strategy Pioneered by
Advanced Nuclear Science and Technology”. Rokkasho-mura, Aomori, Japan, July 30, 2010.
Abstracts and presentations, 2010 - Rokkasho-mura Nuclear Research Centre. Pp.1- 6.
10. K. German, A. Melentiev, V. Misharin et all. Nucl. Med. Biol. V. 37, No 6, (2010), P. 678.
11. K. German, A. Melentiev, V. Misharin et all. Tc-DTPA sediments formed in Tc-hydrazineDTPA-nitric acid solutions. Proceedings of the International Symposium on Technetium andOther Radiometals in Chemistry and Medicine – Forum Brixen – Bressanone Congress Center(Italy) September 8-11, (2010). pp. 47 - 50.
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12. C. S. Gong, W. W. Lukens, F. Poineau, K. R. Czerwinski. Inorg. Chem., (2008), 47 (15), pp.
6674–6680.

ISTR2011 Delegates in Red Hall and Winter Garden of Presidium RAS

A. Maslennikov

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2.6.
COMPOSITION AND CATALYTIC PROPERTIES OF TECHNETIUMBASED SEDIMENTS AND INTERPHASE SUBSTANCES FOUND
IN THE URANIUM-PLUTONIUM SEPARATION STAGE
OF THE PUREX PROCESS
D.N. Kolupaev1, A.B. Melentev1, A.N. Mashkin1, V.A. Misharin1, A.V. Ananyev2,
V.P. Shilov2, K.E. German2, I.G. Tananaev2
1

FSUE “PA“Mayak”, Lenin st., 31, Ozersk, Russian Federation, 456780, mayak@po-mayak.ru
Institution of Russian Academy of Sciences – A.N. Frumkin Institute of Physical Chemistry andElectrochemistry of RAS, Leninskiy prosp., 31-4, Moscow, Russian Federation, 119071

2

KEYWORDS: technetium complexes, sedimentation, spent nuclear fuel, hydrazine
ABSTRACTThis paper represents results of study of the composition and properties of sediments andinterphase substances (IS’s), found in the uranium/plutonium reductive separation apparatus, usedin the Purex-type extraction reprocessing of VVER-440 and BN-600 spent nuclear fuel (SNF) on
the RT-1 facility. It was found, that both sediments and IS’s are based on the compounds oftechnetium and palladium and accumulate beta- and gamma-active nuclides. Frequency factors
were obtained for the homogeneous and heterogeneous reactions of hydrazine and tetravalenturanium catalytic oxidation in presence of sediments and IS’s. The polyaminocarboxilic nature of
Tc compounds in sediments and IS’s was shown with the methods of spectral analysis.
INTRODUCTION
The SNF reprocessing by Purex requires extraction of U and Pu to the 30% TBP solvent in
the HA extraction apparatus. The largest part of fission products (FP) remain in the aqueous stream
and are directed to HA waste. Although, some FP’s are extractable, and among them Tc should be
noted as the element extracted close to 99% [1]. The flow of the loaded solvent (containing U, Pu,
Tc, some other elements) goes to the most important and at the same time - very complicatedoperation of U/Pu separation.
The separation of U from Pu in the extraction reprocessing of VVER-440 and BN-600 SNF
on the RT-1 facility of PA «Mayak» is achieved by using the reductive agent, containing U(IV),hydrazine, and the complexing agent (DTPA) for stabilizing purposes. As a result of this operation,
Pu is reduced to trivalent inextractible state and U remains in solvent stream. The simplified
flowsheet of the HA extraction cycle (incorporating the U/Pu separation apparatus) is shown on
fig.1.

Figure 1 – The flowsheet of the HA sycle
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Generally the extraction process functions properly, but sometimes the rapid consumption of
reductive agents is observed at the U/Pu separation stage, and this leads to the malfunction of Pu reextraction. The causes of these incidents remained unclear.
During the investigation of the problem the presence of sediments at the interphaseboundaries and at the bottom of some stages of the the U/Pu separation mixer-settler array was
uncovered, and samples were taken for research [2].
EXPERIMENTAL
The samples of sediments and IS’s were obtained from the stages of the industrial mixersettler array with the peristaltic pump. Dissolution of sediments and IS’s was carried out at 70-80oC
in 6-7 M HNO3 with addition of some H2O2. The inorganic components in solutions were
determined by spectroscopy. UV-vis spectra were obtained with Varian Cary 50 and Perkin ElmerLAMBDA 35, gama-ray spectra - with SEG analyzer, and x-ray fluorescence spectra - with BHV-7
X-ray tube.
Processes leading to sedimentation and formation of IS’s were studied using modeled HNO3N2H5NO3-Tc-DTPA-UO2(NO3)2 solutions, representing the systems typical for the operation of
U/Pu reductive separation. IR spectra of the modeled precipitates which were formed in thesesystems, were acquired with Specord M80 and Thermo Nicolet Nexus, XRD - with DRON-3, and
ESR with Brucker ESP 300. [Tc] was determined by beta-scint. counting at Beckman 6500 andwith UV-vis spectroscopy.
For kinetics studies portions of sediments and IS’s were placed in thermostatically controlledvials, HNO3 solutions containing hydrazine were added. A row of kinetics experiments was also
carried out with two phase systems where the aqueous HNO3 phase contained the tetravalenturanium along with hydrazine, and the organic phase was 30% TBP in hydrocarbon diluent.
Constant mixing was applied to these systems with the overhead stirrer. U(IV) and hydrazine
content in the solutions were analyzed by titration at the exact time intervals.
RESULTS AND DISCUSSION
The composition of sediments and IS’s
The sediments and IS’s were located in mixer-settler array stages from 2 to 7 (this zone of theextraction apparatus prior to the feeding stage serves for the Pu re-extraction), and varied in density,
color and quantity, with darker and more dense formations being found in stages 3, 7.
Elemental analysis had shown that the inorganic macrocomponents of sediments and IS’s are
Tc and Pd, and their content may exceed 30 and 6 g/dm3, respectively. Some steel corrosion
products like Fe, Ni and Cr were detected. Uranium was also present, but it was not strongly
associated to the sediments and IS’s, probably being just mixed with the samples during theextraction process. Further research revealed that the total deposits of Tc in the extraction array may
reach up to 520 g, deposits of Pd – up to 200 g. The content of non-organic components in samples
is given in table 1.
Table 1 – Components of sediments and IS’s found in the stages of mixer-settler array
Component, g/dm3
Stage
Phase
№
U
Tc
Pd
Fe
Cr
IS
0,30
9,09
1,88
0,60
3
Sediment
30,10
6,25
425
IS
0,30
5,92
0,62
0,30
4
Sediment
1,75
27,14
4,30
0,75
IS
0,10
9,00
0,54
0,05
7
Sediment
1,00
8,83
1,39
6,38
1,75
IS
4,87
1,41
8

Ni
0,40
0,70
-

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Analysis has also shown that the sediments and IS’s absorbed and concentrated the beta- andgamma-active nuclides (table 2). The most part of their activity is determined by 106Ru, 125Sb and134
Cs. 137Cs came second. The significant presence of 95Zr and 233Pa was also detected.
Table 2 - Activity of radionuclides in samples and accompanying phases for the 3rd stage of U/Pu
separation mixer-settler array
Exposure
Nuclide activity, Bq/dm3
Phase
dose,
233
125
106
137
95
Ра
Sb
Ru
Cs
Zr
µR/sec· dm34474Solvent
0,022
4,4·105,3·102,1·102,0·104,2·103IS
7,1
6,1·1077,8·1095,6·1071,5·107
5
5
7
5
Aq.
0,021
3,0·102,3·101,5·103,6·108,7·10488
10
7Sediment
14,7
1,2·101,5·101,6·103,2·102,6·107

According to table 2 both sediments and IS’s are very active compared to the aqueous andorganic phases, taken from the same mixer-settler. Concentration factors for gamma-emitting
nuclides in the samples were calculated as a ratio of nuclides activity in sample to the activity inaccompanying phase (aqueous for sediments and organic for IS’s). These factors, varying from 10
to 103 (depending on the stage of mixer-settler array) are presented in table 3. The largest
consecration factors were calculated for Cs and Ru in formations at the stage 3 of the extraction
array.
Table 3 - Accumulation factors for radionuclides in sediments and IS’s
Nuclide accumulation factor
Stage №
Phase
233
125
106
137
Ра
Sb
Ru
Cs
IS
1150
370
2800
3
Sediment
400
650
1060
890
IS
60
40
130
4
Sediment
140
640
1350
20
IS
10
190
30
7
Sediment
480
110
610
20
8
IS
90
50
270

95

Zr

360
300
440
550
-

The causes for sedimentation
Palladium may become included in sediments and IS’s dew to its fast reaction with the HN 3
(the decomposition product of hydrazine) forming the insoluble Pd diazide, which in the presenceof the organic phase (30% TBP) turns to a thick interphase film capable of absorbing different solid
particles [3]. The reduction of Pd to metal by U(IV) may also contribute to this element
accumulation in the extraction array [4], and it was shown that sediments containing Pd may form
the IS’s because of the azide formation even if there is no available Pd in aqueous phase [5]. But nodata was available about the possible formation of insoluble Tc compounds causing theaccumulation of this element in the extraction apparatus under the conditions of the U/Pu
separation. In order to find out the reason for Tc deposition, modeled solutions imitating theaqueous phase of the extraction system were studied, and it was found that formation of sediments,
fine flakes and thin films on the sides of reaction vessels takes place, although the process is not
fast.
Sedimentation occurs within the large interval of [HNO3] (from 0,5 to 3 M) and isaccompanied with catalytic decomposition of hydrazine in presence of Tc, and only if DTPA or
EDTA complexing agents are present in the solution.
On the initial stage of hydrazine-Tc interaction fast reduction of highly extractable septivalent
form of technetium along with the decrease of free DTPA content was observed, but no sediments
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011were found at this stage (figure 2). Intensive sedimentation was detected visually and by thedecrease of overall Tc content in solution along with the reoxidation of reduced Tc, and the gradualincrease of [Tc(VII)]. Tc reoxidation occurred after the residual concentration of hydrazine in thestudied solutions fell below 10% of the initial concentration. The presence of [UO2(NO3)2] (0.21mol/l) and increase of acidity speeded up the hydrazine decomposition and provided conditions formore rapid sedimentation.

% of the component in
the solution
_

100
80

4

60

3

40
20

2

Figure 2 – Behavior of themodeled solution components[Тс]0 = 2·10-3 M; [DTPA]0 = 0,5·10-2
M; [HNO3] = 1 M;
[N2H5NO3]0 = 0,63 M; 25C
1 – N2H5NO3; 2 – Tc(VII); 3 – DTPA;
4 – Tc (total)

1

The Tc-DTPA precipi-tates
0
100
200
300
400
500
600 were isolated from mother solutions
and studied with a variety ofTime, hmethods (IR, ESR, XRD). The
precipitate was completely X-ray amorphous. The IR spectrum of the precipitate (figure 3)
demonstrated clearly that it is not TcO2 and gave evidence for the presence of strongly coordinated
DTPA. Characteristic absorption shapes in 1350-1600 cm-1 and ~1040 cm-1 shifted towards lower
wavenumbers (compared to pure DTPA) indicate that there are carboxylic groups and nitrogencomplexed to metal within the structure of the studied compound.
Figure 3 - The IR spectra of themodeled Tc precipitate (1), DTPA (2),
TcO2 (3) and solid U-DTPA complexonate(4), as studied in [6]

4
3
2

70
60
50
40
30
20
10
0
500

Trancmittance, %01Similar IR spectrum was
obtained for the solid uranium-DTPA
complexonate known from literature 4000 3500 3000 2500 2000 1500 1000
Wavenumber, сm-1
[6]. ESR gave evidence of tetravalent
Tc present in the compound. The Tc - DTPA ligand ratio was found to be close to 1:1. Further
investigation wascarried out utilizing EXAFS and XANES methods on the K-edge of Tc, and thepossible structure of the compound – the polynuclear oxo-bridged Tc polyaminocarboxylate, wasproposed [7].
Catalytic properties of sediments and IS’s
Due to the high Tc and Pd content (both elements being well known for their catalytic activity), thestudy was carried out for catalytic reactions of oxidation of the reducing agents used in theextraction reprocessing of SNF in presence of modeled and really isolated sediments and IS’s. The
frequency factors (K’) for the reaction of hydrazine oxidation were obtained at variabletemperatures and [HNO3].
With the heterogeneous catalyst (sediments or IS’s) the induction period typical for thereaction was not distinguishable, but K’ in all such systems was found to be lower, then in presenceof the homogeneous catalyst – the HTcO4 (table 4). The catalytic activity of modeled sediments wasmore significant compared to the activity of the really isolated ones, which may be explained by thepossible passivation of real sediments during their continuous contact with the environment of the
U/Pu separation apparatus.
The studied catalytic process became more active upon heating. The rise of temperature from40 to 60 oC increased the K’ for the real sediments more than tenfold.
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Table 4 - Catalytic decomposition of hydrazine in presence of different Tc-containing compounds[HNO3],
Half
К’ of hydrazine
Duration of fast
Tc added to solutions
t, °C
mol/L
decomposition of
decomposition,
reaction period,as*hydrazine, h
h-1
h
0,5
2,5
0,307
4,5
HTcO4
1,0
1,4
0,454
1,5
0,5
3,2
0,186
-**
Modeled sediment
40
1,0
2,3
0,303
-**
0,5
>6
0,035
-**
Real sediment
1,0
>6
0,058
-**
IS
1,0
4,0
0,180
-**
0,5
0,7
1,320
1,0
HTcO4
1,0
0,4
2,500
0,5
0,5
0,5
1,830
0,5
Modeled sediment
60
1,0
0,45
1,950
0,5
0,5
1,5
0,494
1,5
Real sediment
1,0
0,9
0,757
1,0
* - [Tc] in all systems = 1·10-3 mol/l** - fast reaction period was not distinguishable

For more precise imitation a row of experiments was carried out with two phase systems andthe U(IV) was added to the aqueous phase along with hydrazine. In these systems the constantmixing was applied using the overhead stirrer (figure 4).
А

100
1

80

% of U(IV)

Figure 4 - Oxidation of U(IV) (А) and hydrazine (B) ina two-phase system (HNO3 - 30% TBP/ dodecane) in presenceof HТсO4, Pd2+ and Tc-containing sediment; [HNO3] = 1 M;
[N2H5NO3] = 0,24 M; [U(VI)] = 0,336 M; [U(IV)] = 0,022 M;
40C; phase ratio 1:1; Catalyst added: 1 – non; 2 – [Pd] =2·10-4 M; 3 – [Tc] = 2·10-3 M; 4 – modeled sediment ([Tc] =2·10-3 M upon complete dissolution)

60
40

2

20

4
3

% of N 2H5 NO3

A system with no catalytic additives has shown0
only a minor decrease in U(IV) content because of
0
1
2
3
4
complex autocatalytic reactions in the organic phase,
Time, hthere the protective influence of hydrazine is absent [8]. B 100
1
In a system there Pd in a form of PdCl2 was added, U(IV)80
oxidation was significant and some hydrazine wasconsumed. Formation of flakes (metal Pd) was observed
260
within 40 min from the beginning of the experiment.
With Tc added as HTcO4 the rate and yield of oxidation
40of both U(IV) and hydrazine exceeded these parameters
4of all other systems.
20
The K’ for the reaction of U(IV) oxidation were
30
0,026; 0,42; 1,74 and 0,69 h-1 for the two-phase systems
without any additives, with PdCl2, with НТсО4 and with
0
1
2
3
4
modeled Tc-based sediment, respectively.
Time, hIt was also found that the catalytically active
components may be leached from the sediments and the IS’s into the solution adding thehomogeneous factor to the heterogeneous catalytic process. Along with the rapid changes oftemperature or HNO3 content, the Tc (Pd) transfer to liquid phase becomes significantly more
intensive, although the complete dissolution of sediments does not occur at the extraction process
operating conditions (figure 5).
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At [HNO3] < 1,5 M the effect of temperature on the dissolution of samples was insignificant.
At 60 C less then 60% of Tc, and at 40oC – about 50 % were leached from thesamples within one hr. But with increase of acidity in solution from 1,5 to 3,0 M the raisingof temperature from 40oC to 60oC caused almost complete leaching of Tc from the sediments. In 10
M HNO3 Tc was leached to 99% at all temperatures, although there was still some undissolved
material left in the test sell.

% of Tc leached

o

100

3

2

75

Figure 5 - Dissolution of the modeled Tc sediment at different
temperatures and [HNO3]; Temperature: 1 – 25C; 2 – 40C; 3 –60CIncrease of [HNO3] or temperature in the industrial
scale extraction process may lead to the dissolution of25
sediments and burst runout of catalytically active
02468 10 components to the aqueous phase. The described effects
HNO3 , mol/l
occurring in presence of sediments and IS’s may be one ofthe possible reasons for the malfunctioning of the extraction process characterized by rapid
destruction of reducing agents and the rise of temperature.

50

1

CONCLUSION
The composition of sediments and IS’s formed in the stage of U/Pu separation of the RT-1
flowsheet was defined. Tc and Pd are the major components of these sediments and IS’s. It was
found, that sediments and IS’s collect and transport corrosion products and β, γ – emitting nuclides(106Ru, 125Sb, 137Cs, 233Ра, 137Cs). The accumulation factors for some of these nuclides were found tobe as high as 103.
In the system Tc-HNO3-hydrazine-DTPA within the large interval of [HNO3] Tc forms anindividual insoluble compound – Tc polynuclear polyaminocarboxilate. This compound is formed
mainly on the final stage of Tc-hydrazine reaction when Tc(IV) is slowly oxidized and most part ofhydrazine is expended.
The Tc (Pd) containing sediments and IS’s have an explicit catalytic effect on the process ofhydrazine and U(IV) oxidation in HNO3 aqueous solutions. Increase of temperature or acidity
speeds up the oxidation and initiates Tc leaching to aqueous phase. These factors may lead to fast
consumption of reducing agents and malfunction of the U/Pu split apparatus.
ACKNOWLEDGMENTS
The work was supported by RFBR grant 09-08-00153-a.
REFERENCES
1.
2.

3.
4.
5.
6.
7.
8.

A.N.Mashkin, K.K. Korchenkin, N.A. Svetlakova et al, Radiokhimia. 44: 34-40 (2002).
A.B. Melent’ev, V.A. Misharin, A.N. Mashkin, I.G.Tananaev, K.E.German. Abstracts of
the 6-th Russian conference on radiochemistry, 12-16 Oct. 2009. Moscow.- Ozersk, FSUE
Mayak, 2009, p. 209.
B.Ya.Zilberman, A.N. Mashkin, G.A. Lelyk et al, Radiokhimia. 32: 45-49 (1990)
V.S.Koltunov, A.S. Kostikov, K.M. Frolov, Radiokhimia. 32: 60-66 (1990).
D.N.Kolupaev, A.N. Mashkin, A.B. Melent’ev, I.G. Tananaev, Radiation Safety Problems.
№1: 9-16 (2011).
G.I. Petrjak, G.S. Lojkina, S.S. Zelentsov, Radiokhimia. 16: 386-390 (1974).
K.E.German, A.B. Melent’ev, Ya.V. Zubavichus et al, Radiokhimia. 53: 155-161 (2011).
V.I. Marchenko, V.S. Koltunov, K.N. Dvoeglazov, Radiokhimia. 52: 97-110 (2010).

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2.7.
INTERACTION OF MICROORGANISMS AND RADIONUCLIDES
T.V. Khijniak
Winogradsky Institute of Microbiology of RAS (Prospect 60-letiya Oktyabrya 7/2, Moscow,
Russian Federation)
Keywords: sediments, bacterial reduction of radionuclides, 99Tc, 237Np, 239Pu, 244Cm
Abstract:
Interaction of microorganisms with metals and radionuclides is quite complex and includes
biosorption, bioaccumulation, bioleaching, biomineralisation and biotransformation. The
microbial activity affects the red/ox state of elements and therefore affects their mobility in theenvironment. The reduction of long-lived radionuclides including Pu(V,VI), Np(V) and Tc(VII) isreviewed and the biogeochemical mechanisms of reduction are discussed.
Introduction
Pollution of environment by toxic materials such as heavy metals and radionuclides is an
important problem facing the postindustrial society. The radioactive wastes were intensively
produced in course of fission materials production during 50 past years and it will being
increasingly generated by various plants of nuclear fuel cycle. Safe treatment of the wastes of thistype is an imperative to further nuclear cycle development. The laboratory studies show thatduring underground storage of waste 95-97% of radionuclides (Sr, Ru, Cs, Ce) precipitated.
Remained solution contains long-lived elements (Tc, Pu, Np, U), which can migrate with porewater and therefore radioactive contaminated area enlarged. Microbial metal reduction results inthe precipitation of a low valence, reduced form of the element, and have therefore been proposed
as a strategy to treat contaminated waters.
There are many papers about using of biotechnological techniques for purification from uranium,
strontium, cesium and iodine. In this study we paid attention to radionuclides of higher
importance with respect to long-term radioactive waste control. Technetium-99, neptunium-237,
plutonium-239, curium-244 are long-lived and mobile radionuclides and have high potential forbiological uptake. The cases of penetration of those radionuclides to the environment werereported. However, published data on biological and physico-chemical mechanisms of actinide
sorption by lake sediments and on kinetics of these processes are incomplete. We chose two lakes
with different trophic types to test behavior of radionuclides (99Tc, 237Np, 239Pu, 244Cm) incase of its penetration of water reservoirs as a result of catastrophes. Several low-valence forms ofradionuclides are possible and it is important, therefore, to identify the products accurately so thatthe long-term stability and environmental mobility of microbially reduced species can bepredicted.
Results and Discussion.
Two typical fresh water lakes were chosen according to different biological productivity: highly
productive eutrophic lake (Beloye Kosino, Moscow region, Russia) and a dystrophic lake
(Shatura region, Russia) where organic matters present as humic and fulvic acids.
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Fig.1. Uptake of long-lived radionuclides by sediments of utrophic lake Beloe, Moscow region.
[Tc] 0 = [Np] 0 = [Pu] 0 = 10-5 M.

Fig.2. Temperature influence on Tc-99 uptake by eutrophic sediment.
The initial concentrations of radionuclides were 10-5 - 10-4 M. Our laboratory model experiments
indicate that uptake of radionuclides reached 98-99% during one summer season and biologicalprocesses play the significant role [1,2]. Our results shown that uptake of actinides from water
should be considered as two-phase process – physico-chemical and biological phases (Fig.1) [2].
First phase was very fast (during 1-2 hours) and could be described as a sorption of actinides on thesediment particles. Neptunium sorption had fast uptake during first hour when 60% and 50% of
initial input was sorbed by sediment of eutrophic and dystrophic lakes, and a slow bioaccumulation
period when neptunium uptake was completed in 1 and 2 months for eutrophic (Fig.1) and
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dystrophic lakes, respectively [3, 4]. In case of plutonium and curium, the first phase takes in 1 houralso, but sorption of radionuclides reached only 34-38% [2, 5]. The Tc uptake rate was almost
constant, the time of half-uptake being 0.5-0.6 and 1 month for eutrophic and dystrophic lakes [2, 69]. The complete Tc accumulation by sediment took place after 1 and 2,5 months, respectively.
Temperature dependence of radionuclides uptake was investigated also [3, 10]. Temperaturedependence of Tc uptake rate was not very high, the uptake halftimes increasing from 16 to only 18
days with the temperature decrease from 15 oC to 6 oC (Fig.2). The microflora of lake played
important role in the accumulation and reduction of some radionuclides [6, 11]. The additional
donor or acceptor of electron can change uptake rate of Tc. Lactate or cut reed as the electron
donors increase technetium bioaccumulation rate in case of sediments from eutrophic lake. The timeof half-uptake take place in 10 days instead of 20 (Fig.3). Addition of sulfate or nitrate decreases
the rate of Tc accumulation due to competition relationships between SO42- or NO3- and TcO4- - thetime of half-uptake of technetium prolong up to 30 days instead of 20 days (Fig.3) [3, 10]. In caseof dystrophic lake organic matter decompose very slowly and not complete and form a lot of humic
and fulvic acids. These acids have very high molecular weight, complex structure and can madecomplex with many elements, with heavy metals in particularly. Our experiments show that being added towater phase of dystrophic lake finally about 3% of Tc and 30% Np were bounded in water soluble
complexes with natural humic acids precipitating on acidifying water to pH 1 (concentration of humic acids
was up to 0,5%) [10, 12]. In the eutrophic lake water, the humic acid concentration was below 0,005% andthe fraction of Np bound to them was no more than 1% [10, 13, 14].

Natural water (NW)
NW + Sulfate 100 mg/l
NW + Nitrate 100 mg/l
NW + reed 1200 mg/l
NW + Lactate 100 mg/l

Tc-99 in water phase, %

100
80
60
40
20
0
0

20

40

60

Time, days
Fig.3. Substrate impact on Tc-99 uptake by eutrophic sediment.

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011[Tc] in water phase, %

100
80
60
40
20
0
0

1

2

3

4

5

Time, month

Fig.4. Multiple addition and uptake of Tc-99 by eutrophic sediment
The desorption of technetium was carried out with H2O, 1M HCl, 1M NaClO4 or 15% H2O2. The
desorption factors were 0.05, 0.05, 0.08 and more 0.99 thus indicating the technetium was sorbed
by sediments as a reduced forms, which were generated by microorganisms. Thus, bacterial
reduction of Tc is the main mechanism controlling the Tc transport to bottom sediments.
Microbial metal reduction results in the precipitation of a low valence, reduced, form of theelement, and has therefore been proposed as a strategy to treat contaminated waters [16]. Sulfatereducing bacteria Desulfovibrio desulfuricans (Fig.5) [17], metal-reducing bacteria Shewanella
putrefaciens [18] and Geobacter sulfurreducens [19], Escherichia coli [20] and thermophilicarchaea and bacteria Thermoterrabacterium ferrireducens, Tepidibacter thalassicus [21] were
found to be capable of reducing Tc(VII) at neutral pH. In this case very soluble pertechnetate was
reduced to insoluble TcO2 via direct enzymatic reaction. Under acidic conditions,
Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans can also reduce Tc(VII) to lowvalency forms with formation of brown colloid [22]. Some haloalkaliphilic bacteria (identified as
Halomonas) isolated from soda lakes and soils were capable to reduce Tc(VII) under the alkaline
anaerobic conditions (Fig.6) [23]. Several reduced species, including Tc(V), Tc(IV) and Tc(III)were identified under such conditions (Fig.7). The results of extraction clearly show that after 4days of incubation under anaerobic alkaline conditions, an average of 76% of the 0.25 mM ofpertechnetate had been reduced by haloalkaliphilic cultures to Tc (IV) and Tc(V) species. Within
the pH range from 8 to 11, the anionic complex TcIVO(OH)3(CO3)- is the dominant one.

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Fig.5. The reduction of pertechnetate by Desulfovibrio desulfuricans. [Tc] 0= 0,25 mM. 1control, 2- lactate, 3- formate, 4- H2.

Tc-99 in the medium, %

100
80
60
40
20
0
0

20

40

60

Time , days

Fig.6. The reduction of pertechnetate by haloalkaliphilic bacteria. [Tc] 0= 0,25 mM, 1control, 2 – Tc(IV), 3 – Tc(VII).

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Fig.7. Spectrophotometric analysis of bacterial spent medium under alkaline condition. [Tc] 0= 0,25 mM, pH
9.8, t= 30 C. A- 0 hour, Tc(VII) at290 nm , B- 3 days, Tc(VII) and Tc(IV) at 512 nm, C- 12 days, Tc(VII),
Tc(IV) and Tc(III) at 628 nm, D – Tc(III) disappeared with addition of O2.

The results of this research may be important for the fate and transport of technetium in theenvironment. Haloalkaliphilic heterotrophic microorganisms could provide a perspective for thebiotechnological treatment of low level radioactive waste. Our isolates were capable of using
formate, acetate, lactate, methanol and ethanol as electron donors and pertechnetate, nitrate,
selenite, selenate, tellurite, chromate and elemental sulfur as electron acceptors [23]. This wide
variety of substrates and resistance to high concentration of technetium make such bacteria
attractive for biotechnological applications. However, the formation of highly electronegative
soluble Tc(IV) carbonate complexes indicates that it may be necessary to reassess current
concepts of Tc transport in anaerobic, carbonate enriched ground waters, where Tc mobility has
been considered to be controlled by the low solubility of TcO2.
Conclusions.
Microbial reduction provides a great potential for remediation of low level radioactive wastes.
Acknowledgments: The work was supported by Russian Foundation for Basic Research grant 1004-01500a.

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References.
1. German K.E., Khizhnyak T.V., Lyalikova N.N., Peretrukhin V.F. In: RussianRadiochemical Conference, Dubna, Abstracts, p.144 (1994).
2. Peretroukhin V.F., Khizhnyak T.V., Lyalikova N.N., German K.E. Radiochemistry (Russ).
38/5: 471-475 (1996).
3. Khijniak T.V., German K.E., Firsova E.V., Peretrukhin V.F., Medvedeva-Lyalikova N.N.
Ecological Chemistry (in Russ). 10/4: 233-237 (2001).
4. Peretroukhin V.F., German K.E., Firsova E.V., Khijnyak T.V., Lyalikova N. N. Oralpresentation at the 2-d Russian conference on radiochemistry. Dimitrovgrad, 27-31
October 1997. Extended abstracts, p.144-145.
5. Firsova E.V., German K.E., Peretroukhin V.F., Khijniak T.V. Fourth International
Symposium and Exhibition on Environmental Contamination in Central and Eastern
Europe. 1998. Abstracts, p.160.
6. German K.E., Khizhnyak T.V., Lyalikova N.N., Peretrukhin V.F. 5-th Annual Conferenceof the Nuclear Society, Moscow. Nuclear energy and Industry. Obninsk, 27 June - 1 July
1994, p. 498 - 499.
7. Khizhnyak T.V., German K.E., Lyalikova N.N., Peretrukhin V.F. The role ofmicroorganisms, algae and organic remains of sediments in the behaviour of technetium infresh water lakes. In: Abstracts 5-th Intern. Conf. on Chemistry and migration behaviourof actinides and fission products in the geosphere. MIGRATION'95. Saint-Malo, France,
Sept. 10 - 15 , 1995, p.107 - 108.
8. Khizhnyak T.V., Lyalikova N.N, German K.E., Peretroukhin V.F.Uptake of technetium bybottom sediment of fresh water lakeand role of microorganisms in this process. Papers ofRussian - Japanese Seminar on Technetium, July 1-5, 1996. p.38 - 39.
9. German K.E., Khijnyak T.V., Peretroukhin V.F., German E.S., Firsova E.V. Behaviour oftechnetium in eutrophic and dystrophicfresh water lakes. The second Japanese-Russian
Seminar on Technetium. Shizuoka, Japan, Nov. 29 - Dec.2. 1999. Abstracts, pp.50-51.
10. German K.E., Firsova E.V., Peretroukhin V.F., Khijnyak T.V., Simonoff M.
Radiochemistry (Russ). 45/3: 229-235 (2003).
11. German K.E., Khizhnyak T.V., Lyalikova N.N., Peretrukhin V.F. Technetium
bioaccumulation by microorganisms. Journ. of Nuclear Biology and Medicine. 38/3: 406(1994).
12. German E., Firsova E., Khijnyak T., Lyalikova N., German K., Peretroukhin V. Studies ofneptunium behavior in fresh water eutrophic and dystrophic lakes. Journees des actinides,
1999, 15-17 april , Luso, Portugal, Abstracts, pp.39-40.
13. Khijnyak T.V., German K.E., Firsova E.V., Medvedeva-Lyalikova N.N. Natural analog
studies of Tc and Np behaviour in freshwater eutrophic and dystrophic lakes.
Migration’99, Abstracts, Seventh International Conference on the Chemistry and
Migration Behavior of Actinides and fission Products in the Geosphere. Incline Village,
Lake Tahoe, Nevada, USA, September 26- October 1, 1999, p.48.
14. German K.E., Firsova E.V., Peretrukhin V.F., Khijnyak T.V. Simonoff M.
Bioaccumulation of Tc-99, Pu-239 and Np-237 by bottom sediments оf freshwhater lakesof Moscow Region. Extended synopses of reports. The 3-rd Russian-Japanese Seminar on
Technetium, (Dubna, June 23 – July 1). – Dubna: JINR, 2002 – ISBN 5-85165-706-5. P.
14-16.
15. Barinova F.A., Bugaeva N.G., German K.E., Peretrukhin V.F. MODEL EXPERIMENTS
ON BIOACCUMULATION OF TECHNETIUM AND THORIUM BY BOTTOM
SEDIMENTS OF EUTROPHIC LAKES OF MOSCOW AND UDOMLYA REGIONS.
International Symposium on Technetium - Science and Utilization - Oarai, Japan, May 24- 27, 2005.
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16. Lloyd J.R. FEMS Microbiol. Rev. 27: 411-425 (2003)
17. Lloyd J.R., Ridley j., Khizniak T.V., Lyalikova N.N., Macaskie L.E. Appl. Environ.
Microbiol. 65: 26-91-2696 (1999)
18. Wildung, R.E., Gorby, Y.A., Krupka, K.M., Hess, N.J., Li, S.W., Plymale, A.E.,
McKinley, J.P., Fredrickson, J.K. Appl. Environ. Microbiol. 66: 2451–2460 (2000)
19. Lloyd J.R., Sole V.A., Van Praagh C.V.G., Lovley D.R. Appl. Environ. Microbiol. 66/9:
3743-3749 (2000).
20. Lloyd, J.R., Cole, J.A., Macaskie, L.E.. J. of Bacteriology 179: 2014–2021 (1997)
21. Chernyh N.A., Gavrilov S.N., Sorokin V.V., German K.E., Sergeant C., Simonoff M.,
Robb F., Slobodkin A.I. Appl. Microbiol. Biotechnol.. 76/2: 467 – 472 (2007).
22. Medvedeva-Lyalikova N.N., Khijniak T.V. Mikrobiologiya, 65 (4): 533-539 (1996).
23. Khijniak T.V., Medvedeva-Lyalikova N.N., Simonoff M. FEMS Microbiol. Ecol. 44/1:
109-115 (2003)

At the Poster Session (G.Sidorenko, A. Miroslavov and H. Braband)

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2.8.
LAYERED HYDRAZINIUM TITANATE: REDUCTIVE ADSORBENT FOR
IRREVERSIBLE IMMOBILIZATION OF TECHNETIUM
S.N. Britvin, Y.I. Korneyko1, S.V. Krivovichev, W. Depmeier2.
Department of Crystallography, Geological Faculty, St. Petersburg State University (Universitetskaya Nab. 7/9, St.
Petersburg, Russian Federation)
1- V.G. Khlopin Radium Institute (2-nd Murinsky Ave. 28, St. Petersburg, Russian Federation)
2- Institute for Geosciences, University Kiel (Olshausenstr. 40, Kiel, Germany)

Layered Hydrazinium Titanate - 9 Å (LHT-9) is a new nanohybrid compound related to a family of
lepidocrocite-type layered titanates. Its chemical composition corresponds to the formula(N2H5)0.5Ti1.87O4·aq. LHT-9 combines redox functionality of hydrazine, ion exchange properties oflayered titanate and high specific surface area due to its quasi two-dimensional crystallites [1].
Superposition of reductive and ion exchange properties allows using LHT-9 as effective adsorbent
capable of uptake of more than 50 elements of the Periodic system, with adsorption loadings
approaching 20 wt. %. Ions of completely diverse chemical behavior, like pertechnetate anion TcO4and cationic cesium Cs+ can be simultaneously adsorbed by LHT-9 involving reduction and ion
exchange mechanisms, respectively. Herein we describe the adsorption properties of LHT-9 relative
to the problem of 99Tc fixation [2]. Reductive precipitation is considered as the best way for fixationof Tc [3]. The proposed reductants (Fe(0), Fe(II), NaBH4, sulfides, bioreduction), however, possess
obvious drawbacks including (1) rather narrow pH working range and (2) inapplicability ofadsorption products for long-time disposal of Tc. Hydrazine is well known reductant for
pertechnetate, but the reduction products have strong tendency to retain unprecipitated in the parent
solution [3]. LHT-9 overcomes this problem by irreversible in-situ adsorbtion of Tc(IV) onto
nanocrystalline layered titanium dioxide matrix. Having rather wide working range from pH 1 to
10, LHT-9 is capable of Tc uptake from acid (HTcO4), neutral (KTcO4) and alkaline (KTcO4 +KOH) solutions, with uptake capacities up to 10 wt. %. It is even more important that adsorption
products are therefore ready-to-use precursors for inexpensive one-pot preparation of stable Synroctype titanate ceramics. Tc was found to incorporate into rutile (Ti,Tc)O2, hollandite K(Ti,Tc)8O16
and metallic Tc phases, the latter being considered as the most durable form for long-time Tc
disposal [4]. Besides of removal of Tc from concentrated HLW solutions, LHT-9 can be used as
effective additive into cementous waste forms allowing long-time disposal of Tc from low-level
nuclear wastes containing trace amounts of pertechnetate ion.
Acknowledgments: The work was supported by Russian Federal Programme “Cadres” (contract
02.740.11.0326) and internal budget grant of St. Petersburg State University (no. 3.37.84.2011).
References.
1. S. N. Britvin, S. V. Krivovichev, W. Depmeier, O. I. Siidra, D. V. Spiridonova, V. V. Gurzhiy,
A. A. Zolotarev, Patent Application PCT/EP2010/001864 (2010).
2. N. N. Popova, I. G. Tananaev, S. I. Rovnyi, B. F. Myasoedov, Russ. Chem Rev. 72: 101-121(2003).
3. B. Gorski, H. Koch, J. Inorg. Nucl. Chem. 31: 3565-3571 (1969).
4. N. P. Laverov, S. V. Yudintsev, B. I. Omel’yanenko, Geology of Ore Deposits 51: 259-274(2009).

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2.9.
Re AND Tc IN CERMET WASTE FORMS
S.V. Yudintsev*, E.E. Konovalov**, B.S. Nikonov** IGEM RAS, 119017 Moscow, Staromonetny 35, syud@igem.ru** FSUE «SRC RF – IPPE», 249033 Obninsk, Bondarenko 1

Method of producing matrices for joint immobilization of actinides and Tc by self-sustaining
high-temperature synthesis, SHS has been suggested. More than 20 samples consisting of REE-Algarnet (a target phase for actinides) and alloy (host for Tc) were obtained and studied. At the firststage radionuclides were replaced by Sm or Nd (imitator of REE-actinides fraction) and Re (Tc),
one experiment was carried out with addition of technetium-99 along with Re.
Main phases of these ceramic – metal waste forms (or cermets) were REE-Al-garnet (60-70
vol.%), glass (15-20 vol.%), and alloy (10–15 vol.%). Sm and Nd enter into the garnet and glass,
Re forms alloys with iron group elements or molybdenum. In spite of high temperature Re and Tc
did not evaporate during SHS. Compositions of the metallic inclusions in cermets and partitioningof the elements of interest (Re, Tc) between co-existing phases were analyzed.
The results are compared with published data on (Re,Tc)-containing alloys prepared bysintering or melting in high-temperature Joule-heated furnaces and by arc melting route.
Compositions of the Re-containing alloys in cermets and equilibrium phases in the Fe-Re and MoRe systems are discussed. Alternate method for synthesis of alloys with Tc is inductive melting in acold crucible.
Special attention was paid to analysis of conditions for the Tc-containing forms safe
geological disposal. The repositories should be located in crystalline rocks at depth of 500 m or
below with slightly alkaline (pH  8) and reducing (Eh < 0) properties of the underground waters.
Indicator of such a geochemical media is a presence of minerals of Fe (II). In these environments Tc(IV) will be stable with a very low solubility of its solid phases – TcO2×2H2O or TcO(OH)2.

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2.10.
ELECTROCHEMICAL AND SPECTROELECTROCHEMICALINVESTIGATIONS OF TcO4- ELECTROREDUCTION
IN ACIDIC MEDIA
M. Chotkowski, A. Czerwiński
Faculty of Chemistry, University of Warsaw (Pasteura 1, 02 – 093 Warsaw, Poland)

Despite many years of research on TcO4- ions electroreduction in the acidic solutions themechanism of this process is still not fully understood [1]. Recent studies [2] indicate that in thehighly concentrated H2SO4 solutions the TcO4- ions transform into TcO3(OH)(H2O)2. Generally, inthe acidic solutions multistep mechanism is postulated. As a result of the subsequent steps of the
Tc(VII) ions electroreduction the different forms of Tc at lower oxidation states [3-5] are formed.
The aim of our study was to elucidate the mechanism of the Tc(VII) ions electroreduction ondifferent surfaces (Au, Pt, RVC - reticulated vitreous carbon) and in a wide range of sulfuric acidconcentrations (0.5-12M). Our study were carried out using electrochemical techniques (such as
cyclic voltammetry, chronoamperometry coupled with UV-Vis spectroscopy and rotating ring discelectrode technique (RRDE)). The best characterised electrochemical waves are observed for gold
surface. In strongly acidic solutions are recorded two main cathodic waves. Spectroelectrochemicalmeasurements show that in the first step of discussed process one-electron, reversible reduction of
TcO4-/TcO3(OH)(H2O)2 to Tc(VI) is observed. In the next step the formation of Tc(III,IV) (λmax=
505 nm) is observed. The results indicate the mixed chemical(disproportionation) andelectrochemical pathways for generation of Tc(IV) species. Tc(IV) ions can be reversibly reduced
to the Tc(III) ions (λmax = 670 nm). The stability of Tc (IV) and Tc (III) ions increase withincreasing concentration of H2SO4 in the solution. Further measurements using the rotating ringdisk electrode allowed to provide us with additional informations regarding this process. In thehydrodynamic conditions two currents were recorded. The activation energy of the electroreduction
process calculated for limiting current recorded at potentials lower than 0.4V vs. SHE in 4M H2SO4
was 12.30 ± 1.14 kJ * mol-1.
Acknowledgments: The work was financially supported by Faculty of Chemistry UW (BW –191202).
References.
1. Rard, J. A.(ed.); Chemical Thermodynamics of Technetium, Elsevier: New York, 1999, pp. 7496.
2. F. Poineau, P.F. Weck, K. German, A. Maruk, G. Kirakosyan G., W. Lukens, D.B. Rego, A.P.
Sattelberger, K.R. Czerwinski, Dalton Trans. 39(37): 8616-8619 (2010)
3. G. Horányi, I. Bakos, J. Electroanal. Chem. 370: 213-218 (1994).
4. O.Courson, C. Le Naour, F. David, A. Bolyos, A. Maslennikov, N. Papadopoulos, Czech. J.
Phys. 49:, 687-694 (1999).
5. B. Pihlar, J. Electroanal. Chem., 102: 351-365 (1979)

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2.11.
STABILIZATION OF RHENIUM (VI) COMPOUNDS IN SOLUTION AND
USING THEM IN ANALYSIS
L.V.Borisova,1 V.V.Minin2
1

Vernadsky Institute of Geochemistry and Analytical Chemistry Russian Academy of Sciences, Kosygin str. 19,
Moscow, 119071 Russia
e-mail: borisova19@yandex.ru
2
Institute of General and Inorganic Chemistry RAS, Moscow 119071, Leninsky str. 31. Russia.

Keywords : rhenium (VI), complex compounds, stabilization in solution, analysis
Abstract :The usage of the compounds with “unusual” oxidation states of rhenium (VI) is mainly determinedby the possibility of their stabilization in solution. The stable Re(VI) oxohalide complexes (ReOCl 5, ReOBr4) and series complexes with S-containing organic ligands in different systems ( ReO4- ,ReOCl5- , ReOBr4 – HCl (H2SO4) – L – solv.) has been established. The S-containing organic
ligands ( dithionaphtol (DTN), monothiophenols and others) forms a stable broun-violet
complexes with rhenium, which characterized by specific electron (UV-VIS) and magnetic (ESR)
properties. On the basis of the properties of Re(VI) compounds a number of high specifity andsensitive methods ( ESR and ESP) of rhenium determination have been developed . Methods wereused for determination of rhenium concentration in different natural and technical materials.
Introduction
Rhenium, being a typical transition element, is characterized by a whole series of states of oxidation( from +7 to –1), which it realizes in its compounds , manifesting differing reactivity and specificproperties. Among them a special place is occupied by Re(VI), having one unpaired electron 5d1,
exhibiting paramagnetism and characterized by specific parametric resonance (ESR) spectra in its
compounds. They have not been used in practice, because of the absence of simple methods for
obtaining of them in solution under usual conditions. The use of Re(VI) compounds deals with thepossibility of their stabilization in solutions.
To improve the stabilization of the compounds of Re (VI) and create systems with stable forms of
Re(VI), we studied the interaction of the Re(VII) and oxohalogenide complexes of Re(VI) with thenitrogen- and sulfur-containing organic ligands. The optimal conditions of complexes formations
and ESR spectrum parameters have been determined. The quantitative formation of stable,paramagnetic Re(VI) complexes in acid, neutral and organic solution, equilibrium diagrams of Re
compounds, their properties (redox, complex formation, catalytic, etc), mechanism of kinetic
reactions were studied by us with the use of UV/VIS, IR, ESR, kinetic spectroscopy and othermethods [1]. The cycle of our works on the stabilization of the compounds of Re(VI) in solutions
made it possible to identify several systems where these compounds had adequate stability in thesolutions and in the air, which made it possible to use their properties to develop the firstquantitative methods for determining rhenium - photochemical, catalytic, ESR (and ESR spin-trap)
and others methods [ 1 ] and apply them to analysis of rhenium- containing materials.
In this work we investigated complex of Re(VI) with sulfur –containing organic ligands in thesystems: (ReO4- ), ( ReOCl5- ), ( ReOBr4 ) – HCl (H2SO4 ) – L – CHCl3 and used them in analysis .
Experimental
Reagents: HReO4 , KReO4 , hydrochloric and sulphuric acids – analytical grade. ReOCl5- and
ReOBr4 were prepared earlier [ 2 ], as it is shown below. Oxomonothiophenols and dithionaphtol
heve been synthesized in Inst. of Physical Chemistry ( AS Azerbaijan ). 0.1 M solutions of this
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ligands was prepared by dissolving them in CHCl3. Apparatus: UV – Vis spectra were taken atSpecord M- 40, ESR spectra – with Brucker E- 680X “ELEXYS”.
The oxochloride complexes of rhenium (VI)
Rhenium (VI) oxochloride complex ReOCl5- , stable in solutions, is formed in the following
systems: ReOCl52-, (ReO2.aq), (ReO4-) -H2SO4(H4P2O7) -HCl [ 3- 5 ], and the optimum conditionsof its formation have been determined. It was also shown that solutions of the complex had atypical light absorption spectrum with an intensive band in the visible spectral range in contrast Re (IV, V) chloride complexes and ReO4—ion, the intensive bands of which lie in the UV-range. The
spectra parameters are given in Table 1.
Table 1. Parameters of electron spectra of some rhenium ions

Ions
ReO4-

λ max. (ε max.)
230 ( 3.6.103)

Ions
ReOCl52-

λ max. ( ε max.)
240 (5.6.103), 410 (31),480 (26), 750 (23)

ReOCl5-275 (6.0.103), 430 (4.0.103),560 (800)

ReCl62-281.5 (1.13.104 )Compounds of Re(VI), having one unpaired electron on the next-to-last 5d-electron shell ( 5d1,
s=l/2) exhibiting paramagnetism and characterized by specific ESR spectra. The parameters of ESR
spectrum of Re(VI) oxide chloride ( ReOCl5- in H2SO4 ) complex are following:g‫׀׀‬g┴A‫× ׀׀‬10-4, cm -1 A┴ ×10-4, cm - 1
2.01
1.76 640
329
The presence of specific electron and ESR spectra has made it possible to develop a number ofquantitative methods of rhenium determination on the basis of the formation of theoxopentachloride complex of rhenium.(VI) [ 6 ].
The guantitatively formation of ReOCl5- complex have been established in following system,
containing Fe( II ) as the reducer: Re(VII)-(H2SO4+HC1)-Fe(II) [ 7 ].
The use of iron (II) as a reduction agent allows to quantitatively reduce Re(VII) to Re(VI) in
practically no time. It means that the formed compound is characterized by an intensive absorption
band at 430 nm, reaching the maximum at Re(VII) : Fe(II)=1:1.
Systems Re(VII)- HCl- hν ; Re(VII)-(HCl+H2SO4)-hν
We studied the photochemical reduction of rhenium (VII) to ReVIOCl5- in the hydrochloric acidmedia and in mixtures of conc.HCl and H2SO4 [ 8 ]. The mechanism of the changes in solutions
was studied with the use of flash photolysis [ 9 ]. The formation of rhenium (VI) oxochloride
complex can be represented by the following scheme:hνCl(Re VIIO3Cl3 )2- → [(ReVIIO3Cl3)2-]*→ ( ReVIO3Cl3)3-+ Cl•(1)+↓H ,Cl(Re VIOCl5)- + H2O
The quantitative formation of a stable complex of ReOCl 5- was achieved by irradiation of the 98%
H2SO4 and 2% HC1 solution, containing rhenium (VII), in quartz cells (l=1 cm) with the UV-lightof lamp BUV-15 (ν max =39400 cm -1).
It is shown that the solutions achieve stable optical density, when irradiation does not exceed 20-30
min. The formation of this complex was also confirmed by characteristic ESR spectra.
Spectrophotometric and ESR methods for rhenium determination, based on photochemical
production Re(VI) in conc. H2SO4 have been developed with limit determination 1 g /ml.
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Thus, the photochemical reduction of rhenium (VII) to rhenium (VI) enables conducting
reduction without introducing special reagents – reducers, and that is the priority of the method.
System Re(VII), Re(V) – H2SO4- Br The formation of rhenium (VI) oxobromide complex was established in the systems: Re(VII) –H2SO4 –Br_ , Re(VII) – H2SO4 – Br- - Solv. [10,11]. Complex ReOBr4 in system
ReO4 - -H2SO 4 –Br- is based on the reaction:
2 Re (VII) + 2 Br- —> 2 Re(VI) + Br2(2)

and has the advantages (a) readily, stable, perrhenate as starting material, (b) a quantitative andrapid reduction at room temperature, (c) after removal of bromine, ReOBr4 can be quantitatively
extracted into organic solvent and (d) product will not be subject to hydrolysis or oxidation incontact with the acid. Optimal conditions for ReOBr4 formation have been chosen. It has beenshown that ReOBr4 forms in conc. H2SO4 (> 16 M), Re: Br- ratio from 1:20 to 1:50, in 20-30 min
after adding KBr, and remains stable for 2 hr and more. Absorption spectra of ReOBr4 solution insulphric acid has the following parameters: ε = 2200 ± 140 (ν = 18000 cm -1) and 2050 ± 100 (ν =15300 cm -1).
The ESR spectrum has the following parameters: g║ =2.17 ± 0.005, g ┴=1.765 ± 0.005, A ║=495 ±10 Гс, A┴=340 ± 10 Гс [12-14]. No impurity ions practically complicate the determination by the
ESR technique. Thus, fast and high selectivity spectrophotometric and ESR methods for rhenium
determination, based on the formation of rhenium (VI) oxobromide complex are suggested.
Rhenium (VI) oxotetrabromide is quantitatively extracted by chloroform, toluene and other solvents[11]. The Beer's law is valid for the ReOBr4 extract in toluene within the rhenium concentration
range of (2.5-50).10-4 M. The specific conditions of ReOBr4 formation and the possibility toseparate it from impurities by extraction have enabled the development of a high selectivity methodof rhenium quantitative determination both in the spectrophotometric version and the ESR.
Results and Discussion.
Systems ReO4-, ( ReOCl5-), ( ReOBr4) – H2R
A number of organic sulphur-containing compounds form complexes with Re(VI), thechromophorous properties of which provide the possibility to use them in analysis. The highsensitivity reactions of rhenium with toluene-3,4-dithiol (H2Tdt), quinoxaline-2,3-dithiol (H2QS2)
and thiophenoles in systems ReO4- ,( ReOCl5- ), ReOBr4 – H2R - solv. by the spectrophotometricand ESR methods have been studied. The primary rhenium (VI) compounds were obtained with theuse of the above methods in mixtures of sulphuric and hydrochloric (hydrobromic) acids. Variousorganic solvents, such as chloroform, chloric methylene, toluene, etc., were used as extractants.
Tetraphenylphosphonium and tetraphenylarsonium chlorides were added to maintain the fulltransfer of the rhenium (VI) oxopentachloride complex into the extract. As it has been shown
earlier, the transfer of ReOBr4 into the extract is quantitative and fast. That simplifies the procedureand makes it more efficient for the analysis. The reactions can be represented by the following
scheme (for example with C7H8S2 – H2 Tdt ) [15]:

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System ReOBr4-H2Tdt-chloroform was used to develop a high sensitivity and selective method ofrhenium determination in the spectrophotometric version [16].
It was established that when H2Tdt in chloroform is added to the ReOBr4 chloroform extract, agreen complex with an intensive absorption band at 14500 cm-1 (690 nm, ε = 2.4.104 ) is formed .
The optimum conditions is the 20-30-fold excess of the reagent. The formed complex achieves themost intensive colour in 30-40 min, and it is stable for 10 or more days even when it contacts withwater. The elemental analysis and spectrophotometric method corresponded to the composition
Re:H2Tdt=1:3.
The measurement of the molecular electroconductivity in the chloroform solution has shown thatthe complex is not electrolyte. In the IR-spectrum of the complex there were no bands typical for
the Re-0 in the range of 800 – 1000 cm-1. Solutions of the complex had ESR spectra .It wasestablished that the ESR spectrum has the following parameters: g1 = 2.044, g2 = 2.016, g3 = 1.999.
On the basis of the obtained data was shown that the complex has the following composition:
ReVI(Tdt)3 with a trigonal-prism structure, where (Tdt)2- is the bidentate ligand.
Unlike the galogenide solutions those of the dithiolate complex are characterized by a high stability
in the air, enabling the development of a high efficiency extractional-spectrophotometric method ofrhenium determination applied to the analysis of the concentrated technical sulphuric acid solutions.
Under the optimum conditions of the complex formation the calibration diagram preserves its
straight linearity in the rhenium concentration range of 1.10-5 -1.10-4 M.
System ReVII O4- –- HCl (H2SO4 ) – dithionaphthol (monothiophenols)– CHCl3
The quantitative formation of stable rhenium (VI) complexes with sulfur –containing organic
ligands (L), such as dithionaphthol (DTN), mono-thiophenols (their derivatives) has been
established in the systems, containing perrhenate- ion in acid (HCl or H2SO4) and organic ligands in
CHCl3 (and also in system ReOBr4 – CHCl 3 – L) with stirring in combination with UV/ VIS, IR,
ESR and other methods. Complexes of rhenium with dithionaphtol and butylthiophenol havestability in solution in air and specific absorbance spectra with intense bands in the visible region of
the spectrum and the electron spin resonance (ESR) spectrum characteristic of rhenium (VI).
Optimal conditions of complex formation in the system Re (VII) – HCl –DTN – CHCl3 are the100 – 200 – fold excess of DTN, 11.5 M HCl, Vorg = Vaq ,  = 40-50 min (stable for 2 or more
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011days). Optimal conditions of complex formation in the system ReOBr4 – CHCl3 – DTN are the 5 –fold excess of DTN in CHCl3 , τ = 5 min (stable for 5 or more days).
The composition of complex corresponded to the ratio Re: DTN = 1 : 2 , as it was determined bymolar ratio methods (Fig.1). Formula of complex can be described as[ ReVI O( C10H5OHS2)2]o.
The extract of this compound ischaracterized by absorption spectrum withthe parameters -  max=505 nm ,  max = 1.5x
lg(Dx/(Do–Dx))104 (Fig. 2). Solutions of the complex had
ESR spectra (Fig. 3). It was established that
the ESR spectrum has the following
parameters: g II = 2.059, g ┴ = 1.979, AII =446 G , A┴ = 34.9 G.
After treatment of complex extract by 0.5 M
NH4OH, all elements (except Re complex)
pass in aquatic-alkaline solution. No
LgC L
impurity ions practically complicate thedetermination by the ESR technique.
Fig.1.The composition of complex rhenium with oxidithionaphtol

The specificity of the electronic spectra of rhenium (VI) complexes and their ESR spectra made it
possible to develop quantitative methods for the determination of rhenium.
System Re(VII) – HClconc. – DTN – CHCl3 and ReOBr4– DTN – CHCl3 were used to develop ahigh selective methods of rhenium determination by spectrophotometry and ESR spectroscopy. For
the determination of rhenium the main line in ESR spectrum was used.
The limit of detection for rhenium is 0.15 μg / ml. The methods are applicable to the determinationof rhenium in industrial sulfuric acid and several alloys (Fe-Ni-Re, Mo-Re, W-Mo-Re and other),in fumarole deposits (volcano Kudriavy, Iturup isl., Kuril arc), ground water, plants samples underfield conditions .

2000

3000

4000

5000

Field, G

Fig.2 . Absorbance spectra of complex
rhenium with oxidithionaphtol D=f [Re].

Fig. 3. ESR spectrum of rhenium (VI)with oxidithionaphtol.

Conclusions.
Thus, the stabilization complexes of the unconventional oxidation state of rhenium with Scontaining organic ligands (in the systems , where the oxohalogenide complexes of Re(VI) or
perrhenate-ion used as starting materials) leads to develop the high selectivity and stability methodsof rhenium determination ( in the spectrophotometric version and the ESR) in contrast to
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oxohalogenide complexes, which are sensitive to the action of water and atmospheric moisture(oxygen). .
References
1. L.V.Borisova . Trends in Inorganic Chemistry , review, , 2011 ( in press).
2. L.V.Borisova. Analiticheskaya Khimiya redkih elementov. M.:”Nauka” (1988), p. 169.
3. L.V.Borisova, A.N.Ermakov, O.D.Prasolova.Dokl. AN SSSR ( in Russian).215: 589 (1974).
4. O.D.Prasolova, I.I.Antipova-Karataeva, L.V.Borisova, A.N.Ermakov. Zh. Neorg. Khim.
25:991 (1980).
5. L.V.Borisova,A.N.Ermakov, O.D.Prasolova. Dokl. AN SSSR ( in Russian) .218 : 581(1974).
6. I.N.Marov, L.V. Borisova, A.N.Ermakov. Zh. Neorg. Khim. 20 : 741 (1975).
7. L.V.Borisova, A.N.Ermakov, O.D.A.Prasolova. Zh. Analit. Khim. 31: 504 (1976).
8. M.V.Koroleva, G.I. Romanovskaja, L.V.Borisova, A.K.Chibisov. Khimiya visokih energii.
18 : 47 (1984).
9. L.V.Borisova, M.V.Koroleva, A.K.Chibisov, Y.N.Dubrov. Mikrochim. Acta. 1.: 57 (1986).
10. L.V.Borisova, E.I.Plastinina, A.N. Ermakov. Dokl. AN SSSR ( in Russian)223: 609 (1975).
11. E.I.Plastinina, L.V.Borisova, O.M.Petruchin, Zh. Neorg. Khim. 27: 457 (1982).
12. L.V.Borisova, A.N.Ermakov, E.I.Plastinina, O.D.Prasolova, .Analyst.107:.500 (1982).
13. L.V.Borisova, E.I.Plastinina, A.N.Ermakov,I.N.Marov,V.I. Zhukov. Zh. Analit. Khim. 33 :
978 (1982).
14. I.N.Marov,L.V.Borisova,E.I.Plastinina,V.E.,Zhukov. Zh. Neorgn.Khim. 21: 1641 (1976).
15. L.V.Borisova,E.I.Prasolova,G.I.Evtikova,I.N.Marov. Zh.Neorg.Khim.35:944 (1990).
16. O.D.Prasolova, L.V.Borisova. Zh. Analit. Khim. 44: 346.(1989).

Excursion about Vorobievy Hills, Moscow (M.Ozawa, K.German, F. Poineau, W. Kerlin)
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2.12.
NOVEL APPROACH TO THE MASS-SPECTROMETRIC
DETERMINATION OF TRACE AMOUNTS OF RHENIUM USING ITSCOMPLEXES WITH ORGANIC REAGENTS
A.A.Grechnikov, L.V.Borisova, V.A.Ryabukhin

Vernadsky Institute of Geochemistry and Analytical Chemistry of Russian Academy of Sciences, Kosygin str., 19,119071 Moscow, Russia.

Keywords: SALDI, mass spectrometry, rhenium complexes, quantitative analysis.
Abstract
Novel approach to the determination of trace levels of rhenium has been presented. It involves
the formation of rhenium complexes with organic ligands and the subsequent determination ofobtained complexes using surface assisted laser desorption/ionization (SALDI) technique. A labbuilt, linear time-of-flight mass spectrometer with a rotating ball interface was used in this work.
Two different systems were studied: 1) Re complexes with thiourea or its derivatives, and 2) Re
complex with 8-mercapto-quinoline. SALDI mass spectra of rhenium complexes were obtained inpositive ionization mode. The detection limit of studied complexes was estimated to be less than 1
pg of analytes deposited on the ion emitter, with a potential for improvements.
Introduction
Surface assisted laser desorption ionization (SALDI) is a novel method of ionization oforganic and bioorganic compounds which has been under intensive development over the last
decade. In SALDI the gas-phase ions are formed from molecules deposited on a particular surface
substrate that is irradiated with a pulsed laser [1]. This process does not require the entrainment
action of an added matrix compound for desorption and ionization. A variety of inorganic materials
in the form of powders or monolithic plates were studied as a possible platform for SALDI, and it
was found, that only a few selected substrates have the ability to strongly promote ion formation.
Among them, silicon materials have been and still are the most commonly used as ion emitters in
SALDI due to their high ionization efficiency and relatively soft ionization process. One of theprominent examples is amorphous silicon obtained by RF sputtering [2]. When compared to otherforms of silicon materials, deposited amorphous films have a number of advantages, such as easy
and controllable method of fabrication, greater uniformity over large areas, higher purity and good
reproducibility.
Traditional field that SALDI has been applied to is the determination of organic andbioorganic compounds including drugs, natural products and peptides. Typically, SALDI sample
preparation entails pipet deposition of a several µL droplet of the analyte solution on the surface of
the SALDI-active substrate. The droplet is dried and the substrate inserted into the vacuum chamber
for analysis. The main problem with this approach is very poor repeatability from substrate to
substrate. Recently, the rotating ball SALDI interface with electrospray deposition for rapid,
convenient and reproducible analysis of analytes in liquid solutions was developed [3].
In this paper we demonstrate that SALDI technique can be successfully used for elemental
analysis. The focus of the present work is on the identification and quantitation of trace levels ofrhenium using rotating ball SALDI interface.

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Expermantal
The experimental setup has been described in detail earlier [3].
A lab-built, linear time-of-flight instrument with a 0.60m flight tube was used in this work.
The free flight tube was biased at 2 kV and the rotating ball and substrates were grounded. The
detector signal was processed by a 1 GS/s ADC averager. Two SALDI-active substrates, each
3x3mm, were installed on opposite sides of the ball. One side of the ball was exposed toatmospheric pressure and the other to the vacuum in a mass spectrometer. Analytes were applied
using electrospray deposition to a silicon substrate on the atmospheric side, the ball was rotated180°, and the analyte molecules were ionized and desorbed using laser irradiation. In order to utilize
the analyte more efficiently, the laser focus was scanned over a 1×2 mm 2 sample deposition area
using a computer-controlled dual-mirror scanner.
A diode-pumped Nd:YAG-laser with 355 nm wavelength (third harmonic), 0.5 ns pulse
duration and 300 Hz repetition rate was used for the desorption-ionization. The laser pulse energy
was varied in the range of 10-30 μJ using an attenuator.
Amorphous Si (α-Si) films were deposited on monocrystalline silicon by standard RF
sputtering of Si in a low pressure (10-3 Torr) Ar atmosphere [2]. The thickness of the deposited film
was approximately 0.5 mm.
All chemicals were obtained commercially and used without further purification. Rhenium
complexes with thiourea and its derivatives were synthesized by method referenced in [4]. To 1 mL
of HReO4, containing 1 g Re firstly was added 10 mL of 8 M HCl and then thiourea (Thio) at such aquantity to obtain Re:Thio = 1:10. The mixture was stirred for 3-4 h at room temperature, during
which time a dark brown crystalline precipitate formed. This was filtered off, washed with cold
water and then air-dried. The synthesized complexes were dissolved in methanol-chloroform (1:1)
solvent.
Rhenium complexes with 8-mercapto-quinoline were synthesized by method referenced in [5].
To 8 mL of HReO4, containing 1 g Re was added 37 mL of concentrated HCl and 5 mL of 6%
solution of 8-mercapto-quinoline in concentrated HCl. After warming at water bath, the reaction
mixture was cooled and the synthesized complex was extracted in chloroform. The solutions ofanalyte in methanol-chloroform (1:1) were used for further SALDI analysis.
Results and Discussion
The developed method for the determination of trace levels of rhenium is based on aformation of rhenium complexes with organic reagents and the subsequent determination ofobtained complexes by SALDI technique. The main specific feature of organic reagents is that theyshould contain at least two essentially different functional groups. One of such group has the ability
to form thermally stable complexes with Re while another one provides high effective ionization for
subsequent mass-spectrometric detection.
Two different systems were studied in a view of possible applications for Re determination: 1)
Rhenium complexes with thiourea and its derivatives, and 2) Rhenium complexes with 8-mercaptoquinoline.
All studied complexes are characterized by relatively high ionization efficiency. Also therelatively high mass spectrometric selectivity is obtained as a relatively high resolution, m/Δm, of~800 is realized in mass spectrometer due to a short desorbing laser pulse and to a well defined
ionization zone, located on the active surface of α-Si substrate.

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40000

20000

0

200

400

600

800

m/z

Fig.1. SALDI mass-spectrum of Re complex withphenylthiourea

amu was observed, as it is seen from Fig.1. On
the one hand this yields structural information
about studied complexes, but on the other hand,
can strongly complicate the determination of Re
complexes in the multicomponent mixtures.
For successful discrimination of a targeted
analyte from interfering chemical noise mass
spectra should be “clean” with low chemical
background and with no or very specificfragmentation of ions of analytes. Such spectra
were observed for another studied complex.
Fig.2 shows a SALDI mass spectrum of 5 ng of
Re complex
with
8-mercapto-quinoline
deposited on the α-Si surface from a 500 ng/ml
solution. The base peak in the mass spectrum
corresponds to the molecule ions, and only two
minor fragment ion peaks are observed.
Fig.3A demonstrates the molecular ion
peak derived from the mass spectrum presented
in Fig.2. It should be mentioned, that a
relatively high mass-spectrometric resolution
makes it possible to easy distinguish M and(M+1) peaks. It is seen from Fig.3A that themolecular ion peak consists of several isotopic
lines. Among them the isotopic lines at m/z=521
and m/z=519 are the most abundant. It is wellknown that naturally occurring rhenium is37.4% 185Re and 62.6% 187Re. The ratio of theareas of the peaks at m/z = 519 and at m/z=521
is 37.5/62.5 that is very similar to the Re
isotopic composition. High accuracy ofmolecular mass determination in mass
spectrometer as well as measured isotopic
distribution makes it possible to determine thecomposition of the synthesized complex. Fig.
3B shows the isotopic distribution of the12000

Ion signal, a.u.

Ion signal, a.u

60000

Fig. 1 shows a typical SALDI mass-spectrumof about 50 ng of rhenium complex withphenylthiourea deposited on the α-Si surface
from a 10 µg/ml solution. The peak with the
maximal m/z value in the mass spectrum
corresponds to the molecular ions and hence
gives the information about the composition of
the synthesized complex. According to themass spectrum, the composition of these ions is(ReOL13)+, where L1 is phenylthiourea ligand.
The ability of ionization technique to obtain theintensive molecular ion is very useful inpractical mass spectrometric analysis.
However, the extensive fragmentation ofdesorbed ions in the mass region of 150-350

8000

4000

0
200

300

400

500

600

700

m/z

Fig.2. SALDI mass-spectrum of Re complex
with 8-mercapto-quinoline
A
10000
12500

Ion signal, a.u

80000

7500

5000

2500

0
512

516

520

524

528

m/z

521

B

519

522

Fig.3. Molecular ion peak of Re complex with 8mercapto-quinoline: A) - derived from the mass
spectrum presented in Fig.2, B) – calculated.

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Ion signal, a.u.

molecular ion peak calculated for complex composition (ReOL22)+, where L2 = C9NSH6 (8mercapto-quinoline – H). One can see that the measured molecular peak coincide with thecalculated one, within the error of measurements.
Rotating ball interface allows for deposition
30000
of controlled amounts of analytes. The SALDI
ions signal was measured for different
25000
amounts of Re complexes with 8-mercaptoquinoline over a range of two orders of
20000
magnitude by changing the concentration of15000
the solutions deposited. A typical dependenceof the analytical signal on the mass of Re
10000
complex deposited on the α-Si surface isillustrated in Fig. 4. The dependence is seen to5000
be linear over the studied range. The relative
standard deviation with 7 replicate analyses
0
was less than 10%. These results clearly
0
200
400
600
800
1000
demonstrates that proposed technique can be
Mass, pg
successfully used for the quantitative
Fig.4. Analyte ion signal plotted against the mass
analysis of Re. Limit of detection wasof Re complex with 8-mercapto-quinoline deposited
estimated to be less than 1 pg of depositedon the α-Si surface
analyte, with a potential for improvements.
Conclusion
Novel approach to the determination of trace levels of Re, including the formation of Re
complexes with organic ligands and the subsequent determination of obtained complexes by SALDI
method has been presented. The reported results demonstrate that SALDI technique possesses highanalytical potential for determination of Re in natural and technogenic samples.
Acknowledgments
The authors are grateful for financial support from the Federal Agency for Science andInnovation Programs (grant № 02.522.12.2012) and the Russian Foundation for Basic Research
Programs (grant №11-03-01080-а).
References
1. IUPAC Project 2003-056-2-500.
URL:http://amitpatel745.files.wordpress.com/2010/10/iupac_ms_terms_second_draft1.pdf
2. S.S. Alimpiev, A.A Grechnikov., J. Sunner, V.A. Karavanskii, S.N. Zhabin, Ya.O. Simanovsky,
S.M. Nikiforov. J.Chem.Phys. 128: 014711 (2008).
3. S. Alimpiev, A.A Grechnikov., J. Sunner, V.A. Karavanskii, Ya.O. Simanovsky, S.M. Nikiforov.
Rapid Commun. Mass Spectrom. 25: 140–146 (2011).
4. L.V. Borisova , A.N.Ermakov . Analytical chemistry of rhenium, М., Nauka, 1974, p.99 (inrussian).
5. Yu.A. Bankovsky, A.F. Ievinsh, Z.E. Liepinya, Zhurn. analit. khimii 15: 78 (1960).

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2.14.
METHOD FOR HEXAMMINECOBALT (III) PERRHENATE SYNTHESISFROM PERRHENIC ACID
K. Leszczynska-Sejda, G. Benke, K. Anyszkiewicz, A. Chmielarz, S. Cupial
Instytut Metali Niezelaznych, 44-100 Gliwice ul. Sowinskiego 5, Poland

A method for production of high purity [Co(NH3)6](ReO4)3·2H2O from perrhenic acidobtained by ion exchange method was presented. The perrhenic acid production is based on
sorption of ammonium ions on acid cation-exchange resin – Purolite C160(H) and regeneration of
the ionite with 32% solutions of nitric(V) acid. In the result of thickening of the solution, which is
generated after sorption, perrhenic acid is produced, containing 300-900 g/L Re and Ca < 0.001 %,K < 0.001%, Mg < 0.0001 %, Cu < 0.0001 %, Na < 0.0001 %, Mo < 0.0001%, Ni < 0.0001%,
Pb < 0.0001%, Fe < 0.0001%, NH4+ < 0.0003 %.
Studies into production of dihydrate of hexamminecobalt(III) perrhenate were conducted withapplication of [Co(NH3)6]Cl3 (by Acros Organics) as a source cobalt compound. Also substitutionof the commercial product [Co(NH3)6]Cl3 with the produced in laboratory hexamminecobalt(III)chloride was examined as well as possibilities for direct precipitation of [Co(NH3)6](ReO4)3·2H2O
from cobalt containing ammonia solutions.
It was found out that precipitation of [Co(NH3)6](ReO4)3·2H2O should be conducted fromsolution of Co content at the level of 50 g/L, in room temperature, with 60 % excess of rhenium vs.
cobalt. It is important to use aqueous solution of perrhenic acid where rhenium concentration is over
100 g/L. The combined solutions should be intensively mixed for half an hour so the cobalt
concentration in the solution after precipitation of [Co(NH3)6](ReO4)3·2H2O is <0.001 g/L.
Solubility of the produced compound in water and in selected organic solvents was examined. It
was established that [Co(NH3)6](ReO4)3·2H2O is slightly soluble in water (solubility in 25 °C –0.3 g/L, and in 80 °C – 4.1 g/L) and in classical organic solvents such as ethanol, acetone. It is,however, readily soluble in DMSO and N,N-dimethylformamide. The solubility in room
temperature was 500 and 600 g/L, respectively. It was established that the examined substance isstable in the temperature range up to 60 °C. In the temperature of 80 °C some mass loss wasobserved which prove removal of one water molecule. The temperature increase to 100 °C resulted
in removal of the next water molecule. In the temperature range 100-180 °C a stable anhydrous
hexamminecobalt(III) perrhenate was formed.
Application of the developed method resulted in production of [Co(NH3)6](ReO4)3·2H2O
with efficiency of over 97 %, of following composition: 10.77 % NH4+, 6.22 % Co, 58.93 % Re andcontaining less than 150 ppm of impurities, such as sodium, chlorine, iron, nickel, chromium,potassium, magnesium and lead.

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2.15.
MODERN X-RAY ANALYTICAL INSTRUMENTS
OF BRUKER AXS
D. Golovanov
Bruker Ltd., Moscow, Russia
e-mail: dg@bruker.ru

Bruker company is widely pronounced manufacturer of industrial and scientific research
instruments. Bruker AXS designs and manufactures analytical X-ray systems for elemental analysis,materials research and structural investigations. On the CIS region company is represented by
Bruker Ltd. located in Moscow, Russian federation.
Bruker AXS produces wide range of X-ray diffractometers and spectrometers for different
areas of application. Mentioned systems are installed in the most of leading research and industrial
centers all over the world. That allows one to adopt produced equipment and to develop software
for any urgent request from the customer.
For the “common” phase analysis of small amount of semples we offer table top diffractometerD2 Phaser. System allows one to do quantitative phase analysis and structure determination.
Diffractometer comes fully equipped with evaluation and measurement software. In addition systemequipped with Topas program suite for Ritfeld based profile analysis. Diffractometer is fully selfcontained and require no external water cooling or extra units for operation but only 220 V plug.
For higher level research we offer D8 Advance system. It can be equipped with a set of thermalchambers and X-ray optics. Diffractometer allows operation in different modes: Bragg-Brentano,parallel beam, several types of focusing geometry and others. One of the advantage of the D8Advance is a wide set of detectors: scinti, line position sensitive detectors – solid state and gaseous,energy dispersive and 2-dimensional area detectors. Specially designed mounts allows changes in
configuration without complicated alignment.
The rest of investigation areas can be accomplished with D8 Discover. Diffractometer featureshigh resolution measurement and micro-analysis. System equipped with a wide set of precise X-ray
optics and can be configured with rotating anode, microfocus source or sealed tube on demand.
Bruker Ltd company serves for all kind of customer relation. Our specialists develop a certain
methodic for your measurements. Among sales activity we fully cover guarantee and service issues
for all Bruker AXS customers.

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2.16.
PREPARATION OF 95m,gTc, 96Tc BY IRRADIATION OF MOLYBDEN WITH
ALPHA-PARTICLES AND DEUTRONS
R.A. Aliev
Lomonosov MSU

A method is proposed to produce the short-lived radionuclide 95gTc via formation of the parent
Ru. To produce 95Ru, the bombardment of molybdenum target of natural isotopic composition
with α-particles and the irradiation of ruthenium of natural isotopic composition withbremsstrahlung photons were used.
95

Irradiation of natural molybdenum stack foil target for 15 min with alpha particle beam (1 µA)
followed by radiochemical separation yields 140 kBq of 95gTc and 9 kBq 96Tc.
The 95gTc obtained is of considerably higher purity than those formed by common ways
(niobium or molybdenum irradiation with alpha particles). The main radionuclide impurity (thatcould not be avoided) is a small amount (9.1 × 10−2 %) of long-lived 95mTc isomer.
Attention was also paid to the production of side products such as 95mTc, 96Tc and 97,103Ru, inorder to utilize optimally the energy of the alpha particle beam.

ISTR2011 participants in the Winter Garden of Presidium RAS
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2.17.
MODERNIZATION METHOD FOR PRODUCTION OF FISSION
Mo-99 FROM LOW-ENRICHED-URANIUM FOIL (LEU-FOIL)
Sami M. Alwaer; Jalal; Basim
Tajoura Nuclear Research Center (TNRC)
P.O.Box: 30878, Tripoli – Libya
samiwaer@yahoo.com

ABSTRACT
Tajoura Nuclear Research Center (TNRC), Libya, will implement the technology for 99Mo isotope
production using LEU-foil target (This target is made of a LEU metallic uranium foil inserted
between two concentric aluminium cylinders), to obtain new revenue streams for the TNR-reactor
and desiring to serve the Libyan hospitals by providing the medical radioisotopes. Korean target
will be used in this work which will be irradiated for 72 hours in the reactor core at flux equal to 1.0
x 1014 N/Cm2.S. The target will stay 10 h. in the reactor pool for cooling before disassembling it
inside a hot cell located in the reactor building. The LEU-foil will be transferred to chemical hot
cell pneumatically. A special set up has been designed for the processing of LEU-foil. The set up
consists of the dissolver with controlled pressure, nitric acid will be used for dissolution, cold trap
cooled in liquid nitrogen for removing the fission gases, precipitation of Mo-99 by fresh 2% alphabenzoin-oxime will be done and purification of the final product by using two chromatographic
columns: the first one contains AgC ( carbon coated with silver nitrate) and the second one is acombined column with C, HZO-1 (hydro zirconium oxide) and AgC. The final product of Mo-99
solution will be filtered with 0.22 µm filter. The final radioactivity of Mo-99 expected to be >150
Ci and 95% purity.
INTRODUCTION
Technetium-99m, the daughter product of Molybdenum-99 (Mo-99), is the most commonly utilized
medical radioisotope in the world, used for approximately 20-25 million medical diagnostic
procedures annually, comprising some 80% of all diagnostic nuclear medicine procedures [1,2].
National and international efforts are underway to shift the production of medical isotopes from
HEU to Low Enriched Uranium (LEU) targets [3]. A small but growing amount of the current
global Mo-99 production is derived from the irradiation of LEU targets. The IAEA became awareof the interest of a number of developing Member States that are seeking to become small scale,indigenous producers of Mo-99 to meet local nuclear medicine requirements. The IAEA initiated
Coordinated Research Project (CRP) T.1.20.18 “Developing techniques for small-scale indigenous
production of Mo-99 using LEU or neutron activation in order to assist countries in this field [4].
The more significant world crises are related to the availability of the 99Mo/99mTc generator,
because of its extensive use and the short half life precluding significant anticipation [5]. Tajoura
Reactor is a pool type reactor, moderated and cooled by light water located at the Tajoura Nuclear
Research Center (TNRC). The reactor was designated to carry out experiments in field of nuclear
physics and nuclear engineering, neutron activation analysis, solid state physics and isotope
production. The reactor was put into operation at a power level of 10 MW in September 1983. [6].
The reactor was completely converted to Low Enriched Uranium (LEU, 19.7% of 235U) fuel of typeIRT-4M at the end of 2006; the new fuel is an alloy (matrix) of aluminum and uranium-dioxide(UO2–Al) with aluminum cladding.

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Experimental
Annular Target Assembly Instructions [7]1.0 Prepare the Target Tubes:
Machine the inner and outer tubes the dimensions identified. Clean-off machining fluids from tubes
using standard machine shop method.
1.1 Obtain dimensions of the inner and outer tubes prior to assembly.
a. Measure and record the I.D. and O.D. of the inner tube.
b. Measure and record the I.D. of the outer tube.
1.2 Clean the tubes, use powder-free latex gloves to handle the tubes to prevent particulatecontamination of the weld faying surfaces.
1.3 Place in ultrasonic cleaner containing a solution of detergent for ~10 minutes at ~ 90°C,
thoroughly rinse tubes in running water.
1.4 Bright Dip consists of 90 vol% concentrated H3PO4 / 5 vol% H2SO4 / 5vol% HNO3, thoroughly
rinse tubes in running water.
1.5 Hot-air dry tubes for at least ten minutes at ~ 125°C using a heat gun (Fig. 1).

Fig.1. Inner and outer tubes

2.0 Prepare the Uranium Foil for Annular Target Assembly, two Ready targets have been preparedwith LEU-foils with different sizes Table. 1. shows the measurements for LEU foils.
Table. 1. Measurements for LEU foils
Width
(mm)

Length
(mm)

W1

W2

L

t1

t2

t3

44.1

44.1

76

154

142

124

ID No.
of foil

44.1

1

44.2
2

44.0

44.2

76.1

Thickness(micron)Av. Thickness(µm)

Weight(g)

Weight(U235)

159

152

8.20

1.63

156

105

128

167

162

176

168

169

180

126

158

8.41

1.67

120

157

194

157

155

122

166

148

2.1 Envelope the uranium foil with the precut nickel-foil fission recoil barrier (Fig. 2).

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Fig. 2 Envelope LEU-foil with Nickel barrier

3.0 Annular Target Assembly
3.1 Coat the inside of the inner tube with “dry graphite” , this will act as a lubricant for the draw
plug and prevent the inner tube from galling when drawing the inner/outer tubes together.
3.2 Clean the outer surface of inner tube ends to remove any excess graphite lubricant using a lintfree cloth moist with acetone.
3.3 Make a longitudinal permanent marker/ scribe mark on the outer tube to identify foil gap
position, wrap the uranium/nickel foil around the inner tube, slide the inner tube into the outer tube
and ensure that the foil gap is lined up with the scribed mark on the outer tube (Fig. 3).

Fig. 3 Target assembly

3.4 Electron Beam (EB) weld target ends and Helium leak test the assembled target, Fig.4.

Fig.4 weld the ends

Fig. 5. LEU Target Horizontal,
Vertical Cross Sections, andDimensions.
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3.5 Fig. 5 shows the LEU Target Horizontal, Vertical Cross Sections, and Dimensions [8].

Target Irradiation
The ready target will be irradiated in the Reactor for 72 h. at a flux equal to 1.0 x 1014 n/cm2.S. anda spicial Rig has been made to handel the target during the irradiation, Fig. 6.

Fig. 6 (A) the rig, (B) the rig with the target

Disassempling the LEU target
After irradiation, the target will be cooled in the reactor pool for 10 h. then the target will betransfered to a hot cell in the reactor bulding. Finally the target will be transferd to another hot cellwhich is just near the first one where the target will be dsassempled by using a special cuter (Fig.
7).

Fig. 7. LEU target cuter

Special toole has been made to determine the edges of the LEU target during the disassembling,
another particular piece was manufactured for the purpose of the expansion of the shear
longitudinal tube,( Fig. 8 & 9) respectively [9].

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LEU-foil processing
1. Calculate the concentration of nitric acid needed for 40 mL of dissolver solution. This
calculation is based on the grams of total uranium and grams of nickel fission barrier for thetarget to be processed [10].
Ni + 8/3HNO3 ---- Ni(NO3)2 + 4/3 H2O + 2/3 NO
U + 4 HNO3 ---- UO2(NO3)2 + 2 H2O + 2NO
2. Remove foil from target and prepare for processing, place the foil in the dissolver,and verify it
is setting directly on the bottom (use push tool if necessary).
3. Attach the dissolver to the vacuum pump (using the septum), open the valve between the septum
and the dissolver, and evacuate the air from the dissolver (Fig. 10).

Fig. 10. Evacuate the air from the dissolver

4. Use the syringe to inject a 40 mL of dissolver solution which will be addes to the dissolver
through the dissolver septum. Heat the dissolver by using the heat gun (Fig. 11).

Fig.11. Heating the dissolver

5. When dissolution is complete, stop heating, allow dissolver to cool for 10 minutes and connect
it to the cold finger. A special electric machine has been used for connecting the dissolver to thecold finger (Fig. 12).

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Fig.12. Connecting the dissolver and cold finger

6. By a special crane inside the hot cell the connected dissolver and cold finger have been handled
up and transferred to a special stand to insert the cold finger into the LN-Dewar, and liquid
nitrogen flows to the Dewar (Fig 13). Allow the pressure to stabilize, and then slowly open the
cold-finger and dissolver valves. Keep the cold finger in the liquid nitrogen and allow it to draw
off the gas phase for 30 minutes. Close all valves and disconnect the dissolver from the cold
finger by the same machine described in (Fig. 12). The vacuum inside the dissolver should bemeasured with a pressure/vacuum gauge.

Fig.13 Cold finger in LN-Dewar

7. Set the dissolver upright and vent it through a hypodermic needle. Invert the dissolver and fix it
in its place in the setup and drain the solution into an evacuated double-ended bottle labeled “Raw
Fission No. 1” through a 2-way “Luer-Lok” valve (Fig.14). Inject 25 mL of 1M HNO3 into thedissolver and agitate it with the manipulators, making sure the acid solution wets the entire innersurface of the dissolver, Drain the rinse solution from the dissolver into the “Raw Fission bottle.

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Fig. 14 drain the solution into an evacuated double-ended

8.0. Add NaI carrier, Add 10% AgNO3 in 0.1M HNO3, shake, a white precipitate should form, Add
1.0 M HCl additional Precipitate should form and Add Mo carrier.
9.0. A sample of ~0.5 mL should be collected to measure Mo-99 content of the sample forcalculating process yield.
10.0. Pass the solution through 0.3µm and 0.2µm filter assembly into another bottle (Fig. 15).

Fig. 15 Pass the sol. through 0.2µm filter

11.0 Add 2.5% KMnO4 solution slowly to the raw fission liquor until a deep pink color holds for~30 seconds, Add 1.5 mL of Rh carrier to the raw fission liquor, and shake, Add Ru carrier andshake, Add fresh 2% alpha-benzoin-oxime in 0.4M NaOH to the raw fission liquor, shake well.
Wait about one minute. A white, flocculent precipitate should form.
12.0 Filter the precipitate through a 51-mm fritted-glass column. Make sure all liquid is drained
from the column. Wash the precipitate in the column five times with 10 mL of 0.1M HNO3; shaking
the column well after each wash is injected. Drain these washes into the “Acid Wash” bottle (Fig
16).

Fig. 16 Mo-99 ppt. filtration
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 201113.0 To dissolve the precipitate, inject 0.4M NaOH sol. with ~1% H2O2 into the column, ventthrough a charcoal filter, Heat the column that contains the solution with forced hot air until thesolution begins to boil, drain the dissolved precipitate into a bottle.
14.0 Pass the dissolved precipitate through the AgC column. Gravity controlled flow through thecolumn allows a flow rate of 1 - 3 mL/minute. Rinse the Ag/C column with 0.2M NaOH (Fig. 17).
The sol. should appear clear and colorless. Add NaI carrier to the bottle and add 10% AgNO3 in
0.1M HNO3 solution to the bottle. Shake well, and wait ~5 minutes.
15.0 The slurry in the bottle is fed to the AgC/ZrO/AC combination column. Gravity will allow a
flow rate of 1 -3 mL/minute.

Fig. 17 Ag/C column or AgC/ZrO/AC combination column

16. Using a one-mL syringe, remove ~0.5-mL sample from the bottle and introduce it through theseptum into the QC sample vial.
17. Pass product solution through the .02 µm filter into the final product bottle (Fig. 18).

Fig. 18 Filtration the final product solution through 0 .02 µm filter

18. All the steps have been explained in this paper combined in one setup as shown in (Fig. 19 ).

Fig. 19 Combined setup for Mo-99 production

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CONCLUSIONSThis paper briefly presents the major activities on production of a fission Mo-99 by LEU-foil target as
new scientific achievements in TNRC. A special combined setup has been designed for all the chemical
processes.

ACKNOWLEGMENT
Alhamdulillah for giving me the strength and health for completed this project work until it done.
Not forgotten to TNRC administration for providing everything to this project work. Then I would
like to thank Mr. Ira Goldman and Ed Pradly from the IAEA for guiding and supporting me throughthe many meetings throughout this project. Last but not least, I would like to thank Prof. George
Vandergrift from ANL Institution (USA) how was sharing our ideas. He was helpful that when we
combined and discussed together, we had this task done.
REFERENCES[1] Preliminary Report on Supply of Radioisotopes For Medical Use And Current Developments In Nuclear
Medicine, SANCO/C/3/HWD (2009) Rev. 8, 30 October 2009[2] Report on Molybdenum-99 Production for Nuclear Medicine 2010 – 2020, Association of
Imaging Producers and Equipment Suppliers (AIPES), November, 2008.
[3] The 26th Annual Radiology Conference was arranged in Karachi on 29th – 31st October, 2010 at
Sheraton Hotel Karachi[4] The IAEA initiated Coordinated Research Project (CRP) T.1.20.18 ´Developing techniques for smallscale indigenous production of Mo-99 using LEU or neutron activation´ Vienna, 2005
[5] H. Bonet: 13th RRFM, Vienna, Austria, 22-25.March, 2009, Transactions pp 70-74[6] KNOW-HOW DOCUMENTATIONS: "Tajoura Nuclear Research Design", Building 1, Design
Features of the Control Rod Arrangement in the Reactor Ensuring Replacement with the Fuel Charge Patternin the Core, 622-1-KH-151 (9), 1979.
[7] Leyva, Argentina. “Assembly Procedures for Annular LEU Target”. Workshop on “LEU Foil Target
Fabrication, Irradiation, and Chemical Processing using Modified Cintichem Technique”, BATAN,
Indonesia, 2-6 March, 2006.
[8] Production of Fission Product Mo-99 Using the LEU-Modified Cintichem Process. Feasibility StudyPart 1. University of Missouri Research Reactor. TDR-0102. July 2006.
[9] Bakel, Allen; Vandegrift, George. “Target Disassembly”. Workshop id. BATAN, Indonesia, 2-6 March,
2006 [7].
[10] Vandegrift, George. “ANL LEU-Modified Cintichem Process”. Workshop id. BATAN, Indonesia, 2-6
March, 2006 [7].

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2.P1.
99

Tc TRANSMUTATION TARGET HETEROGENEITY FOR THE
ARTIFICIAL STABLE RUTHENIUM PURIFICATION FROM 106Ru
А.А. Kozar’, V.F. Peretrukhin
Frumkin Institute of Physical Chemistry and Electrochemistry of RAS,
31/4 Leninsky prosp., Moscow, 119071, Russia, kozar@ipc.rssi.ru
99

Tc transmutation can be the source of artificial stable ruthenium 100–102Ru.
Radioactive 106Ru (T1/2 = 369 days) can not be generated by 99Tc transmutation, however itwill appear in the target as fission product from actinide impurities.
The total (U+Pu) impurity is usually about 5·10–8 g per gram of Tc, isolated fromspent fuel by modified Purex process and selective precipitation of tetraalkylammonium
pertechnetate. The fission of all actinide nucleus-impurities is complete during thetransmutation, because of the cross sections of (n,f) actinide reactions are higher in 1 – 2orders of magnitude than that of 99Tc neutron capture.
Therefore the artificial stable ruthenium, prepared from Tc homogeneous target, is
contaminated by 106Ru, which prevents the practical use of the product in non-nuclear field
during ~10 year up to its complete decay.
106

Ru can not be removed from artificial stable ruthenium by chemical methods.
However there is the possibility to remove fission product 106Ru from transmutation
products 100–102Ru during the irradiation of technetium by thermal neutrons using thephysical phenomenon of recoil after nuclear transformations.
The kinetic energy and recoil range of fission fragments, including 106Ru, are higher
than those of transmutation products 99Tc(n,γ)100Tc(β–)100Ru.
If technetium target is manufactured from Tc metal powder with the particles whose
size is compared with the recoil range of 106Ru (about 8 mkm), this radionuclide can escape
the Tc particle.
106

Ru yield from Tc-Ru spherical particle with radius R is following:3

3 R 1 RY   if R≥ R 2 and Y = 1 if R≤ R 2 ,4 R 16  R 
where R – path length of fission fragments in Tc-Ru alloy.

106

Tc particles should be surrounded with a stuff particles, whose role is to immobilize
Ru. Such heterogeneous target should be treated with diluted nitric acid.

The stuff particles containing 106Ru, will be dissolved and removed, whereastransmutation products 100–102Ru together with non-burned 99Tc remained in solid state. Such
recoil separation with Tc particles size 10 mkm provides with the removing about 95% of
106
Ru from irradiated technetium.

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The proposed recoil separation is more simple and cheap method, than additional
purification of Tc from actinide impurities.

Poster Session (A. Kozar and V. Peretrukhin)

G.Shteinberg, B.Bryskin, A. D. Besser, I.D.Troshkina, A.M. Chekmarev, E.A.Ospanov
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2.P2.
THE BEHAVIOR OF TECHNETIUM, AMERICIUM AND NEPTUNIUM IN
THE SPENT FBR (U, Pu)N FUEL AFTER FAST NEUTRON IRRADIATIONAS A FUNCTION OF THE TEMPERATURE
AND BURN-UP
G.S. Bulatov, K.N. Gedgovd, D.Yu. Lyubimov1.
Institution of Russian Academy of Sciences – A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Leninsky prosp. 31-4, Moscow, Russian Federation)
1
ENTERPRISE OF “ROSATOM” - FEDERAL STATE UNITARIAN ENTERPRISE “SCIENTIFIC RESEARCHINSTITUTE SCIENTIFIC INDASTRIAL ASSOCIATION “LUCH”(24, Zheleznodorozhnay st., Podolsk, Moscow region, Russian Federation

Keywords: uranium – plutonium nitride, fast neutrons, fission products, technetium,
americium, neptunium, partial pressures
Abstract:
The thermodynamic analysis of chemical and phase compositions and parameters of evaporation of
the uranium - plutonium nitride U0.8Pu0.2N was carried out depending on burn up (up to 14%) after
irradiation by fast neutrons at temperatures 900 – 2000 K.
It was shown, that accumulation of fission products results in formation of a multicomponent solid
solution on a basis of uranium plutonium nitride containing Np, Am, Zr, Y and lanthanides, andalso separate condensed phases: U2N3, BaTe, CeRu2, LaSe, Rh3Te2, USe, Ba3N2, CsI, Sr3N2, puremetals: Tc, Mo, Ru, Ba and intermetallic compounds: U (Ru, Rh, Pd) 3. The amount andcomposition of these phases is defined at various temperatures and burn up.
Partial pressures of technetium, americium and neptunium above U0.8Pu0.2N have been calculated atvarious temperatures and burn up.
Introduction
The development of new generation of nuclear power reactors previews the utilization of nitride
base fuel, including mixed uranium – plutonium nitride [1]. This kind of fuel may be also used forthe incineration of military plutonium, minor actinides and some fission products before the final
disposal [2].
Calculations
To obtain new data on the behavior of (U,Pu)N under fast neutron irradiation thermodynamic
analysis of the composition of condensed and gas phases of U0.8Pu0.2N0.995 was carried out using
ASTRA-4 software [3] as a function of temperature and burn-up up to 14 %.
Results and Discussion
Irradiation brings to the formation of a complex structure including solid solution based onuranium-plutonium nitride with dissolved americium and neptunium, zirconium, yttrium andlanthanides and some separate condensed phases, namely U2N3, CeRu2, BaTe, Ba3N2, CsI, Sr3N2,
LaSe, Rh3Te2, USe as well as Mo metal, Tc metal and intermetallic compounds U(Ru, Rh, Pd)3.
The content of the mentioned and its change as a function of the irradiation temperature and burn162

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up values was determined (tables 1 and 2). It was found that the content of Tc, Am, Np at 13.6 %burn-up was 0.253; 0.126; 0.018 % wt. correspondingly.
Table 1. Phase composition and concentrations (% wt.) of condensed compounds in U0.8Pu0.2N0.995 at 900 K
and different burn-up

Burn-up, % (U+Pu)
4.5
9(U, Pu, Np,Am,Me)NZ *)92.6840
84.9070
U2N3
4.41899.270
CeRu2
0.47278
1.0036UPd3
0.398860.86637Mo
0.33600.6929Tc
0.09020.1747URh3
0.17710.3541BaTe
0.14880.3013Ba3N20.07390.1625URu3
0.14790.1864CsI
0.07940.1471
Sr3N2
0.05690.1107
LaSe
0.01480.0297
Sum of phases
99.0996
98.1964*) Solid solution, were Me=Zr+Y+lantanides, z=N/(U+Pu+Np+Am+Me)
Condensed phase

13.6
77.0780
14.1451.55171.36351.03210.25330.52080.45710.27080.21110.20800.16190.044697.2967

Table 2. Phase composition and concentrations (% wt.) of condensed compounds in U0.8Pu0.2N0.995 at 1900 K
and different burn-up

Burn-up, % (U+Pu)
4.5
9(U, Pu, Np, Am, Me)NZ *)97.04594.056
CeRu2
0.3876
0.8968UPd3
0.39890.8664
Mo
0.33600.6929Tc
0.09020.1747
Rh3Te20.15840.3207URu3
0.23770.2990USe
0.01770.0349URh3
0.0236
0.0432Sum of phases
98.6950
97.3746*) Solid solution, were Me=Zr+Y+ lantanides, z=N/(U+Pu+Np+Am+Me)
Condensed phase

13.6
91.0411.42631.36351.03210.2533
0.48640.34330.05180.049196.0455

The values of partial pressures for certain gas phase components over irradiated(U0.8 Pu0.2)N0.995 were calculated for the same range of temperatures and burn-up 13.6% (Fig.1)
The empiric equations describing the changes of Tc, Am and Np partial pressures (atm.) withtemperature were deduced:lg(PTc)=7.55 - 35194/T + 33139/T2(1500 – 2000K)

lg(PAm)=9.43 - 38550/T + 10000000/T2 (1000 – 2000K)
lg(PNp)=6.10 -37230/T - 319050/T2(1500 – 2000K)

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1,E-07
1,E-081,E-09AmN

1,E-10Am

P, atm1,E-11
1,E-12
1,E-13NpN

1,E-141,E-15Tc

1,E-161,E-17Np

1,E-18

1000

1200

1400

1600
Т, К

1800

2000

Fig.1. Partial pressures (atm.) of Tc, Am, Np, AmN, NpN depending on temperature at 13,6% burn-up

Conclusions
The presented results may be used in the design of fast breeder reactors using nitride based fuel, forthe estimation of the risks associated with the behavior of (U,Pu)N in the accidental situation and in
the development of the spent nitride fuel.
References
1. F.G. Reschetnikov, Atom. Energ. 91: 453-458, (2001).
2. R. Thetford, M. Mignanelli, J. Nucl. Mater. 320: 44-53, (2003).
3. Sinjarev G.B., Vatolin N.A., Trusov B.G., Moiseyev G.K Application of the COMPUTER forthermodynamic calculations of metallurgical processes. Science: Moscow, (1982), 267p.

D.V. Drobot, G.S. Shteinberg, I.D.Troshkina in the Red Hall
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N.G. Kravchenko, E.O. Nazarov, T.I.A. Gerber, E.S. German and A.M. ChekmarevInt. adv. Committee: throw lots onto balance for 2014 – Chicago or Las Vegas?
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2.P3.
COMPOUNDS OF CURIUM WITH TECHNETIUM
E. Pichuzhkina, S. Tomilin
Joint Stock Company “State Scientific Center-Research Institute of Atomic Reactors”, Dimitrovgrad, Ulyanovsk
region, ryabinin@niiar.ru

For the last years RIAR has pursued investigations on synthesis of the TPE
compounds, specifically, curium and americium with other elements of the periodic system.
The paper provides the primary results of production and identification of compounds ofcurium-244 with technetium which refer to the complex oxides.
The samples of the technetium compounds with curium were obtained duringcondensation of the curium metal vapours on the technetium substrate and investigated by
the X-ray diffractometry (a DRON-7 diffractometer) at room temperature.
The investigations performed allowed us to obtain the new curium compounds whichwere not known before:- complex oxide Cm6TcO12 that has a hexagonal lattice of the Ho6MoO12 type and the
crystal lattice parameters (CLP) а = 10,552(3) Å, с = 9,879(5)Å;- complex oxide Cm3Tc2O10, the isostructural La3Mo2O10, with the cubic crystal
lattice and the CLP а = 5,592(1) Å.
It is noted that curium remains insoluble in the hexagonal closed-packed technetium
lattice.

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2.P4.
EXTRACTION-CHROMATOGRAPHIC PURIFICATION OF
URANIUM EXTRACT FROM TECHNETIUM
V.I. Volk, K.N. Dvoyeglazov, V.L. Vidanov, L.N. Sergeeva.
Open Joint Stock Company “Academician A.A. Bochvar High-Tech Research Institute of Inorganic Materials”, 5a,Rogova str., Moscow
e-mail: vitaly@bochvar.ru

Uranium purification from technetium in the process of spent nuclear fuel reprocessing
is one of the most complex problems.
Uranium reclaim for separating plant is to be extremely decontaminated from Tc
because of the problems at the sublimation stage caused by volatile TcF6 formation during
uranium recycling process.
There is a conflict between Thorp plant requirements for uranium product after thesecond extraction cycle (Tc content 4 mg/kg U [1]) and ASTM С787-03 standard, which
requires Tc content in uranium hexafluoride less than 0.5 mg/kg U and in some cases [2] thelevel of uranium decontamination from Tc in this product should be less than 1.6 mkg/kg U.
This conflict could be resolved by uranium reclaim additional radiochemical reprocessing
for supplying purified product to the sublimation plant. It is evident that such technology
makes reprocessing process rather expensive.
The aim of the research work was to find and work out such a process, that can
provide effective and not expensive deep uranium purification from Tc on the basis ofextraction spent fuel reprocessing technology.
The solution of mentioned problem is an extraction-chromatographic purification of
uranium extract by usage of aqueous reducing agents solution as a purifying stream. These
agents reduce Tc (VII) to nonextractable Tc (IV).
The process of purifying is carried out in cyclically-countercurrent feed mode ofpurified and purifying streams in a column filled with porous excipient (charged withaqueous purifying stream).
It is shown that depending on composition of the aqueous phase concentration factor
varies from 40 and above. These conditions provide practically complete treatment of
uranium extract.
References
1.
Kopyrin A.A., Karelin A.I., Karelin V.A. “Technology of the production andradiochemical reprocessing of nuclear fuel” M, Atomizdat, 2006, p. 226
2.
Timofeev S.V., Belyaev V.D., Karpov A.A., Shishkov S.U. “ Improving theevaluation control of technetium-99 in the chemical reprocessing technology of NFC naturaland recycled uranium”. Youth NFC: Science, production, ecological safety,
URL:http://conf.atomsib.ru/archive/conf2008/section1/17.doc, date - March 4, 2011.

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2.P5.
METAL-THERMAL IMMOBILIZATION OF HIGH-ACTIVETECHNETIUM WASTE INTO MATRICES BASED ON METAL GLASSCRYSTALLINE COMPOSITES
E.Е. Konovalov, Т.О. Мishevets, S.S. Shulepov, Yu.D. Boltoev
FSUE «SSC RF – IPPE», Obninsk, Kaluga region, Russia
mishto@ippe.ru

In the framework of recycling fuel cycle the problem of high-active waste (HW)
treatment should involve solution of the three major process stages: liquid HWfractionation; calcination (crystallizing) of radionuclides of these fractions predominantly
on inorganic sorbents and immobilization of produced dry sorption-crystal concentrates into
chemically and thermally resistant mineral-like matrix materials suitable for ecologicallysafe disposal. To synthesize such matrices, it is recommended to use metal-thermal selfpropagating high-temperature synthesis (SHS) where Al and Ti are the fuel elements(reducers), and molybdenum oxide and iron oxide are mainly oxidants.
To provide further progress in this direction, the problem of immobilization oftechnetium as most environmentally dangerous product of nuclear fuel fission is consideredin this report. Technetium imitator representing its nearest chemical analog – rhenium inthe form of potassium perrhenate is used in investigations.
When treating high-active waste, Тс-fraction can contain actinides impurities.
Therefore the matrix composite materials synthesized in SHS conditions should incorporate
phases efficiently immobilizing both technetium (rhenium) and actinides (An). To imitate
the last-named, lanthanides (Ln) are used. SHS-produced metallic phases where rheniummolybdenum (Mo-Re) and Fe-Cr-Ni-Re alloys are dissolved with ease have been produced
as matrix material for rhenium immobilization (see the diagram). Matrix materials being
simultaneously synthesized on the basis of stable aluminate or titanate complex oxides like
pyrochlor (Y,An…)2Ti2O7 or Y-Al garnet (Y,An…)3Al5O12 are used to immobilize An.

The present authors are grateful to S.V. Yudintsev and B.S. Nikonov, IGEM RASexperts, for identification of interaction SHS products and analysis of their structure.



The Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry, Russian Academy of Sciences

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2.P6.
APPLICATION OF MODIFIED WOOD MATERIALS FOR EXTRACTION
OF TECHNETIUM (VII) FROM AQUEOUS MEDIUM
N.N. Popova, G.L. Bykov, I.G. Tananaev, B.G. Ershov
A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences,building 4, 31 Leninsky prosp., 119071 Moscow, Russian Federation.
E-mail: popovann@gmail.com

Keywords: technetium, sorption, wood materials, carbonized of wood, nanomaterial "Taunit"
Abstract:
It is investigated sorption ability of some carbon vegetative materials, namely: the charcoal
formed at electron beam processing of vegetative materials; the oxidized coal received at soft
oxidation of wood carbonized and aspen sawdust (wood) in relation to Tc(VII). Influence ofintroduction in a carbon matrix of various modifying additives on the efficiency of sorption ofTc(VII) ions is investigated. Modifying of samples was carried out by urea, a phosphoric acid,thiourea and potassium thiocyanate. The possibility of Tc(VII) extraction from the solutions
modeling underground waters in area of lake Karachaj (FGUP "PO" Maiak»), sea water, etc isshown. The samples synthesized by us have shown high sorption properties, even from solutions
with a high salt background.
Introduction.
Working out of effective methods of concentration and extraction of the Tc(VII) of various
water environments is actual [1]. At a sorbent choice it is necessary to consider not only its
chemical and mechanical stability, but also such factors, as simplicity of reception and availabilityof initial materials. In this connection, recently for extraction of Tc(VII) the modified natural
materials and technological products are more and more used [2]. Therefore search of cheap,
accessible and effective materials for sorption Tc(VII) ions from a liquid radioactive waste andenvironments was the purpose of our work.
Influence of various modifying additives on sorption ability of some carbon materials in
relation to the Tc(VII) is studied.
Experimental.
As objects of research were are taken: (1) coal formed at electron beam processing ofvegetative materials; (2) carbonized of wood; (3) the oxidized coal received at soft oxidation
carbonized of wood by oxygen of air, and also the initial and modified (4) wood (aspen sawdust);(5) activated coal FAS-E and (6) carbon nanomaterial "Taunit".
For improvement sorption properties concerning the Tc(VII) carbon materials have been
modified by processing by phosphoric acid, urea (thiourea) and potassium thiocyanate.
Coal was impregnated with КСNS solutions, was dried up and got warm at 140°С within 1
hour. Other sample was impregnated urea (thiourea) and got warm within 1 hour at 200°С.
The oxidized coal was made of aspen sawdust in two stages. At the first stage sawdust charredat temperature 250-300°С, at the second stage received carbonized was oxidized air at 250-300°С.
Result and Discussion.
It has been shown that oxidizing processing carbonized of wood (2) improves it sorption
properties. It is possible to explain this fact, education on a surface of coal participating in anionicexchange of carbonyl and carboxyl groups at processing on air.
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sorption degree, %

30

2

20
3

10
4

0
0

1

2

3

4

5

contact time, hFig.1. Dependence of sorption degree of Tc(VII) from contact time for 10-3 M HNO3 and following
sorbents: 1 – the coal modified thiourea; 2 – the wood modified by phosphoric acid; 3 – the coal modified
potassium thiocyanate; 4 – the wood modified by urea.

It is received, that at use of the modified carbon materials the Tc(VII) is taken practicallycompletely within the first 30 minutes of contact of phases. Studying of influence medium рН on
efficiency of sorption of the Tc(VII) modified materials has shown, that maximum high sizes of
distribution coefficients are observed at рН 3 on all studied samples.
It is shown that in the acidic medium (рН <4) the Tc(VII) is most effectively taken by thewood modified by urea (Kd = 1,3102 sm3/g from 2М HNO3). In the subacidic and neutral
environment (Fig.1) is the most effective than the Tc(VII) it is taken by the coal modified thiourea(Kd = 58,64 sm3/g from 10-3 M HNO3). In the alkaline environment is better the wood modified byphosphoric acid (Kd = 76 sm3/g proves at рН 9).
It is found that samples FAS-E modified by urea and H3PO4 effectively takes the Tc(VII) of
subacidic solutions HNO3 (Fig.2, 3) with Kd equal 2,4104 and 1,7.104 sm3/g, accordingly. Modified
by urea or H3PO4 samples of "Taunit" (Fig.3) take the Tc(VII) in the same conditions with K d equal
400 and 73 sm3/g, accordingly.
Also sorption properties received by us modified samples of "Taunita" and FAS-E concerning
extraction of the Tc(VII) from the modeling solution of technogenic changed ground waters of areaof the lake Karachaj have been tested (Fig.2). It has appeared that FAS-E, modified by urea,
effectively extracts ions of the Tc(VII) from modeling solutions of complicate structure (Кd = 71,1
sm3/g), and sorption balance also is reached during 30 minutes after the beginning of contact ofphases.

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Кd
100000
1
10000

1000
2
100
3
4

10

1
0

1

2

3

contact time, hFig.2. Kinetics of sorption Tc(VII) on FAS-E, modified by urea at 300оС from various environments(the data on distribution factors is presented in a logarithmic scale): 1 – 10-3 M HNO3; 2 - 0,1 M NaOH; 3 –lake Karachaj water; 4 – 2 M HNO3.

The mechanism of sorption, consisting in localization Tc(VII) on a surface of samples as aresult of course of competing processes - reduction of the Tc(VII) to Tc(IV) being in the sample bymeans of NH2-groups at the expense of its modifying by urea, and also fixing of formed complexes
with participation of this element.
1
2

100

sorption degree, %

80
3
60

40
4
20
5
0
0

0,5

1

1,5

2

contact time, hFig.3. Kinetics of sorption Tc(VII) from 10-3 M HNO3 and V/m=200 sm3/g (V=5 ml, m=25 mg) with
use: FAS-E, modified by urea (1) and phosphoric acid (2); «Taunit», modified by urea (3) and phosphoricacid (4); not modified "Taunit" (5).
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Conclusion.
Thus, researches have shown that as a whole modifying of wood and carbon materials
improves them sorption properties in relation to technetium (VII). Important that the modified
carbon materials possess concerning high sorption abilities in relation to Tc(VII) at its extraction
from the natural (technogenic) objects possessing difficult salt structure. Thus, presence of
extraneous impurity practically does not interfere with extraction of a purposeful element
technetium the modified sorbents synthesized by us on the basis of carbon materials.
References:
1. N.N. Popova, I.G. Tananaev, S.I. Rovniy, B.F. Miyasoedov, Russian Chemical Reviews,
2003, 72, № 2, 115.
2. G.V. Miyasoedova, V.А. Nikashina, Mendeleev Chemistry Journal, 2006, т.L, №5, с.55-62.

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2.P7.
STRUCTURE AND PROPERTIES OF INSOLUBLE TECHNETIUMCOMPOUNDS FORMED IN TECHNETIUM - HYDRAZINE - DTPA NITRIC ACID- SOLUTIONS
K.E. German, A.B. Melentev1, Ya. V. Zubavichus2, S.N. Kalmykov3,
A.A. Shiryaev, I.G. Tananaev
Institution of Russian Academy of Sciences – A.N. Frumkin Institute of Physical Chemistry and Electrochemistry of
RAS, Moscow, guerman_k@mail.ru
1
FSUE “PA“Mayak”, Ozersk, melentev74@mail.ru
2
RRC “Kurchatov Institute”, Moscow
3
Lomonossov MSU, Moscow

The paper presents the results of the study of low-soluble technetium compoundswith diethylenetriaminepentaacetate (DTPA), which finds use as a stabilizing agent in
the extraction reprocessing of spent nuclear fuel. The Tc sediments were studied bychemical analyses, XRD, IR, Raman and UV-VIS, EXAFS and ESR spectroscopy.
The role of the Tc reduction process by hydrazine in mother solutions prior to
precipitation was also evaluated.
It was shown, that the precipitation of Tc occurs when the reduced Tc(IV) is
partially back-oxidized to Tc(VII) with a possible formation of intermediate Tc
species after the most part of hydrazine is expended. The studied precipitate wasdefined as the Tc polyaminocarboxilate of both polynuclear and polymeric nature.
Tc-DTPA ratio was found to be close to 1:1, the huge part of Tc in the polymericsediments being in Tc(IV) valent state. Both carboxylic and amino-groups of the
DTPA participate in the formation of the Tc compound and the coordination offunctional groups from one DTPA molecule to multiple Tc atoms is highly possible.
The Tc-DTPA chelates tend to form large and more complex ensembles with Tc-Tc
bonds and bridging oxo ligands.
Possible structure of the Tc-DTPA compound was modeled (fig. 1) and someways for exclusion of the Tc precipitation during SNF reprocessing were proposed.
Fig. 1 - The model of the possible structure of
Tc-DTPA core

The work was supported by RFBR grants 0908-00153-a and 09-02-12257-ofi_m

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2.P8.
THE BEHAVIOR OF THE ТECHNETIUM - HYDRAZINE - NITRIC ACID TBP SYSTEM IN PRESENCE OF THE COMPLEXING AGENTS
A.B. Melentev, A.N. Mashkin, O.V. Tugarina, K.E. German1, I.G. Tananaev1
FSUE “PA“Mayak”, Ozersk, melentev74@mail.ru
Institution of Russian Academy of Sciences – A.N. Frumkin Institute ofPhysical Chemistry and Electrochemistry of RAS, Moscow

1

The extraction properties of one of uranium fission products – technetium - are of a major
importance for the spent nuclear fuel reprocessing by PUREX-process. Tc(VII) possess significant
distribution coefficient in TBP/HNO3 system thus following the U and Pu at the first extraction
step. Later it may seriously interfere with the U-Pu reductive separation by catalyzing undesirable
red-ox reactions and increasing the decomposition rate of hydrazine, used as a stabilizer. Different
complexing agents may be used to reduce the negative influence of Tc and to control its extraction
behavior.
This paper presents the experimental results on the extraction behavior of Tc and thedecomposition of hydrazine in presence of complexing agents - DTPA and oxalic acid. It was
shown that DTPA did not render significant impact on the hydrazine decomposition in the modeled
hydrazine-containing nitric acid Tc solutions during the 6 hours hold out at temperature of 45 oC,
but the rate of the Tc(IV) reoxidation decreased in presence of DTPA. After the hydrazine wasspent, the yield of Tc(VII) as a result of reoxidation process was found to be significantly lower,
compared to the DTPA-free systems. Upon increase of acidity the chelating properties of DTPA
weakened, so this agent may have limited usability for stabilizing reduced technetium in fuelreprocessing.
Oxalic acid was shown to be more efficient protecting agent for both hydrazine and Tc(IV).
In presence of H2C2O4 hydrazine decomposition rate was slow; the remaining concentration of
hydrazine after 6 hours exceeded 50% of the initial quantity, and only insignificant oxidation of
reduced Tc(IV) was observed. It should be noted, that the initial reduction of Tc(VII) by hydrazine
was slower, than in solutions not containing the complexing agents. The ability to bind Tc(IV)increased for H2C2O4 with the rise of HNO3 content. It was also found, that azide products ofhydrazine decomposition play an important role in the process of stabilizing the systems both withand without complexing agents.
The authors are grateful to Prof. B.Ya. Zilberman for useful discussion of the results. The
work was supported by RFBR grant 09-08-00153-a.

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2.P9.
TECHNETIUM(VII) EXTRACTION WITH HYBRID PHOSPHORNIROGENATED DERIVATIVE LIGANDS
A.M. Safiulina1, K.E. German1, E.I. Goryunov2, I.B. Goryunova2, E.E. Nifantiev 2, I.G.
Tananaev1, B.F. Myasoedov1
1

Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Moscow, Russia)
2
Institution of Russian Academy of Sciences - A.N. Nesmeyanov Institute of Elementoorganic Compounds of RAS(Moscow, Russia)

A new simple “one-pot” synthetic method based on the reagents that are commerciallyavailable is elaborated as a rout to prepare hybrid phosphor-nirogenated derivative ligands likePh2P(O)CHRCHR’R’’ (I a-c; a R = Ph, R’ = R’’ = CN; b R = Ph, R’ = CN, R’’ = COOEt; c R = R’
= H, R’’ = 2-pyridyl), being the substances of potential bioactivity.
The synthetic rout is given by the sequence:

Ph2PCl

H2 O
20oC MeCN

RCH=CRR''[Ph2POH]

20oC THF

Ph2P(O)CHRCHR'R''(I a-c) (yield > 85 %)Thus obtained compounds were tested with respect to technetium liquid-liquid extraction(Organic phase: 0.05 M Ph2P(O)CHRCHR’R’’ in CCl3H, aqueous phase contained 10-5 M KTcO4
in 0.05-0.5M NaOH or 0.05-5.5M HNO3).
Very small distribution coefficients were measured for Tc(VII) extraction from the basic
solutions for the 0.05-0.5M NaOH concentration range studied .
Extraction
fromnitricacid
solutionswasnotable,with
2-[2(diphenylphosphoryl)ethyl]pyridine (I c) being the most effective for 0.7 – 1.5 M HNO3 range.
The data indicate that I-type phosphoryl-nitrirogeneted derivatives fonctionalization isprospective approach to Tc(VII) extraction.
Extraction tests for reduced Tc with the hybrid phosphor-nirogenated derivative ligands likePh2P(O)CHRCHR’R’’ (I b-c; b R = Ph, R’ = CN, R’’ = COOEt; c R = R’ = H, R’’ = 2-pyridyl)
indicate the necessity of temperature pretreatment and the importance of reducing reagent excess inthe aqueous phase.
The work was partially supported by the Program P-17 (Elaboration of new methods forchemical synthesis and design of new materials) of Presidium RAS.

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2.P10.
New materials for immobilization of rhenium, technetium containing waste forthe purpose of their isolation from environment
Murat Abdulakhatov1, Sergey Bartenev2, Mikhail Goikhman3, Alexander Gribanov3, Valery
Guselnikov1, Nikolai Firsin2, Yuri Novikov1, Yuri Sazanov3, Mikhail Zykov2
1

Petersburg Nuclear Physics Institute (PNPI), Gatchina, Russia, e-mail: amk@pnpi.spb.ru
2
V.G. Khlopin Radium Institute (KRI), Saint-Petersburg, Russia
3
Institute of Macromolecular Compounds (IMC), Saint-Petersburg, Russia

Summary
Conditions for immobilization of rhenium and technetium in carbon matrices were
investigated. It is shown that the carbon matrices incorporating the above elements can beproduced by carbonization of composites with ITA-31 polyimide binder, investigatedelements and carbon fabric as reinforcing component. The elements under investigation wereused both in the form of salts or oxides and in the form of their complexes with ion-exchange
resins. The produced composites were carbonized in inert gas (argon) or in vacuum. The
physical-chemical properties of the samples were studied. It was revealed that the resultant
matrices meet the requirements imposed on waste storage and disposal or for transmutation.
1. Introduction
Further development of nuclear power over the world depends to a great extent on solving two main
problems: safety of nuclear power and industrial facilities as well as ecologically reliable andeconomic disposal of radioactive waste (RAW) containing long-lived alpha-, beta- and gamma
radionuclides. Hence, the long-term isolation of RAW from biosphere is an important problem
responsible for further development of nuclear power. Of prime attention is the question on
management of long-lived radionuclides because of their serious hazard if they escape into theenvironment. The point is that the radioactivity of fission products (99Tc, 129I) and minor actinides
such as 237Np and 241Am remains practically at the same level over a period of thousand hundreds
years.
Two variants are best suited to handle these long-lived radionuclides. One of them consists inelaborating a method for immobilization of radionuclides into matrices of high thermal, chemical
and radiation resistance for subsequent long-term storage or final disposal [1]. Another variant istransmutation of long-lived radionuclides into short-lived or stable isotopes in special nuclear
reactors or Accelerator Driven Systems (ADS) [2-3]. It should be emphasized that the both variants
involve production of matrices possessing some properties suitable for prolonged storage or
disposal and transmutation of long-lived radionuclides. The different research centres carry out
research on the development of new techniques for production of reliable matrices. One of suchtechniques consists in production of carbon matrices. Carbon matrices can be obtained bycarbonization of organic substances. To meet the requirements placed on the properties of carbon
matrices being obtained, some composites on the basis of polyimide binder ITA-31 were developed[4]. By producing the carbon matrices it is extremely important to bind nuclides being immobilizedby ion-exchange resins (IER) and complexing agents, which may be used then as components insynthesis of polymer materials. For attaining the stated goal, different materials may be used. In thiswork several commercial IER with high thermal, chemical and radiation stability were chosen. The
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conditions for production of the carbon matrices incorporating rhenium, stable iodine and stableeuropium as the chemical analogues of 99Tc, 129I and 241Am, respectively, were investigated.
2. Methodology
2.1 Initial materials and reagents
Polyimide binder ITA-31 with the following composition was used: dianhydride of 3,3/,4,4/-benzophenonetetracarboxylic acid - 50% and tetraacetyl derivative of 4,4/-diaminodiphenyl ether - 50%.
During composite synthesis the binder was mixed with IER containing rhenium in the form of
perrhenate-ion (ReO4-), iodine in the form of iodide-ion (I-) and europium in the form Eu+3. The
strongly basic anionites like AV-17, VP-1AP, VPB, Amberlite IRA-400 and Dowex 1×4 were used
for preliminary sorption of rhenium and iodine. For preliminary sorption of europium the Russian
IER SF-5 and KB-10 were applied. The carbon fabric of ELUR type was used in composite
synthesis as reinforcing addition for higher strength of matrices.
2.2 Synthesis of composites and their carbonization
Synthesis of composites was carried out in two stages [5]. At the first stage the composite-1
incorporating ITA-31 binder and the IER containing a corresponding nuclide at the ratios of ITA31:IER 8:1 ÷ 1:1 was synthesized. ITA-31 and IER were mixed at 260 – 280°С. Then the carbon
fabric ELUR was added to the resultant composite-1 for its higher strength to afford its masscontent from 20 to 60% in end product (composite-2). The process for production and pressing ofcomposite-2 was conducted at 280-320°С and under excess pressure of 20 – 250 atm., while thecarbonization process proceeded at 600 – 650°С.
2.3 Determination of leach rates
The procedures recommended by International standards were used for determination of leach rates
of rhenium, iodine and europium from obtained matrices [6-7]. ICP MS and emission spectral
analysis was used for determining I, Re and Eu leach rates.
3. Results
3.1 Thermal stability of composites
Taking into account that the radioactive waste containing long-lived radionuclides may be heatedup due to radioactive decay, special attention should be given to thermal resistance of matrices used
for long-term storage or final disposal of RAW. In the previous works conducted by the authors it
was shown that the carbonization process of the composites containing polyimide binders is anefficient method for production of heat-resistant carbon-plastics and carbon-carbon materials on
their basis [4]. However, it was unknown which properties would be typical for the composites
based on ITA-31 and other components of produced matrices. Such components may involve, forinstance, the IER containing the elements under investigation. In the early stage of investigations
some experiments to measure thermal resistance of initial components and related composites were
performed. In Fig. 1 the data are given of differential thermogravimetric analysis (DTA) of VP-1AP
in different chemical forms, including that containing the stable iodine as I-. For correlation
purposes there are also presented the DTA individual results on the ITA-31 and composite
containing ITA-31 and VP-1АP in I- - form.

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The thermal experiments have demonstrated that the
IER containing chemical analogues of investigatedelements enter into chemical reactions with polyimide
binders like ITA-31 and it is possible in such a manner
to produce the heat-resistant matrices for incorporationof the above elements in the course of subsequentcarbonization process. In the range of 600 - 1000°С nosignificant losses of rhenium and europium are observed
and only some marked losses of iodine occur due tolower melting point of its compounds.
3.2 Synthesis of composites incorporating ITA-31
binder and elements under study
The technology for production of carbon-plastics
elaborated in the previous works [4] involved the ITA31 synthesis, the procedure for impregnation of arequired number of carbon-fabric layers, the pressing at
300˚С for 1 hour under excess pressure of 0.1 – 0.5 atm.
The mass ratio between binder and carbon fabric was
1:1.

Figure 1 Results of DTA
1 – ITA-31; 2 – VP-1AP (OH–); 3 –ITA-31+VP-1AP(OH–); 4 – ITA-31+
VP-1AP(OH–)+ELUR; 5 – VP-1AP(NO3–);6 – VP-1AP (I–)

The composite (prepreg) being converted into carbon-plastic state was then subjected tocarbonization in vacuum or inert medium in the temperature range of 20 - 600˚С at a rate of 7 ˚/min.
It should be noted that both prepreg and carbon-plastic produced in accordance with this technology
possess high mechanical and thermal strength. The properties of the carbon-plastics produced byincorporation of IER (for example VP-1AP) into their composition at various ratios between
components are shown in the Table 1.
As it is seen from the results obtained, the strength values of carbon-plastics remain rather high overa wide range of ratios between ITA-31 and IER. These values meet the requirements of the Russianand International standards for RAW incorporating matrices.
However, by using such carbon-plastic molding technique a partial loss of composite occurs due toits flowing out of press mold. In production practice of carbon-plastics containing no harmful
chemical and radioactive substances these losses can be collected and returned into the process
without any radioactive substances these losses can be collected and returned into the process
without any technical difficulties. However, in the case of producing the carbon-plastics (matrices)
containing radioactive substances the composite flowing from press-mold may lead to noncontrolled contamination of equipment and work places.
Other variants of molding matrices were elaborated in this work, which could prevent the noncontrolled losses of RAW during molding.
In the first case the preliminarily prepared prepreg containing ITA-31 and ELUR was crushed tosizes of 5 – 10 mm and mixed on heating with the resin saturated by element being investigated. At
the bottom of the heated press-mold the PM film (polyimide film) was placed and above it the
mixture of crushed prepreg and resin. Pressing was conducted at 5 - 250 atm.
Another variant envisaged mixing of crushed carbon with the resin containing the elements understudy; then, molten binder was added on heating and stirring; the resulting mixture was transferred
into the heated press-mold. Pellets were pressed at 300˚С for 1 hour.
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It was found that among three variants of matrix production the third one is most feasible; in thiscase no prepregs should be preliminarily prepared. This method allows to avoid the non-controlled
losses of investigated elements and to obtain sufficiently strong pellets. Besides, one can introduce
nuclides in a carrier (ion-exchange resin, fullerene soot) as well as in any other solid chemical form,
for example oxide.
Table 1. Properties of composites containing VP-1AP
Properties of С-С composite
Ratio of ITA-31:
VP-1AP

Compression strength,
MPa

Modulus of elasticity,GPа

Mass loss on
carbonization, %

8:1

84

90

12

6:1

79

82

14

4:1

80

81

16

2:1

54

57

17

3.3 Leach rates of investigated elements
Alongside the thermal and strength characteristics the leach rates of immobilized radionuclides ortheir chemical analogs are of significance in defining the chemical stability of matrices. In this work
the leach rate was determined in accordance with the recommendations of the International
standards. Distilled water was used as liquid phase; open surface area for different samples was 1.2– 2.0 cm2. It is determined that the leach rates of rhenium from sample prepared on the basis ofrhenium-saturated resin VP-1AP are 6.8×10-5 – 1.7×10-7 g/cm2×day upon leaching during 1 – 90
days; of europium from sample prepared on the basis of SF-5 resin saturated with europium are
2.5×10-5 – 1.6×10-7 g/cm2×day on leaching within the same time interval; of iodine from sample
prepared on the basis of AB-17 saturated with iodide-ion are 4.8×10-5 – 2.7×10-6 g/cm2×day.
3.4 Radiation stability of matrices.
It is shown that irradiation of the matriсes by neutrons and gamma-irradiation in research reactor
VVR-M in PNPI at neutron-flux density ~ 4·10 n/cm2·s and integral flow ~ 1018 n does not render
the essential influence on their mechanical properties and leach rates of investigated elements. The
values of these parameters for the samples after irradiation practically such, either as for samples
before irradiation.
4. Conclusions

The chemical analogues of such long-lived radionuclides as 99Tc, 129I, and 241Am were immobilized.
Rhenium, stable iodine and europium were used as the corresponding analogs, respectively. It was
shown that the samples carbonized at temperatures up to 600-650°С possess high thermal stability.
The produced samples exhibit high mechanical strength. Their compression strength varies from 47
to 84 MPa, the modulus of elasticity from 49 to 90 GPa. The leach rates of rhenium, iodine andeuropium for different samples range between 2.5×10-5 – 1.7×10-7 g/cm2×day. On the basis of theresults obtained in this work strong matrices of high thermal, chemical and radiation stability fordisposal of long-lived radionuclides can be developed. In our opinion the developed carbonization
method can be used for reprocessing of spent IER and other organic complexing components,
containing of radionuclides and hazardous heavy metals.
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5. Acknowledgments
The work was carried out under financial support of International Science and Technology Centre(ISTC), Moscow (Project #2391).
6. Proposals and Suggestions
The authors of this paper are open to cooperation on mutually acceptable terms.
References[1] «Management of radioactive waste and spent nuclear fuel», MINATOM, Information andAnalytical Collection, Moscow, 2000, issue 2, p. 90.
[2] A.Fernandez et al. "Fuel/Target Concepts for Transmutation of Actinides". Proc. 6thOECD/NEA
Information Exchange Meeting on Actinide and Fission Product P&T (Madrid, Dec. 11-13,
2000).
[3] Michael W. Cappiello, Dana C. Christensen «The Role of LANSE in the Nuclear Energy
Future», Los Alamos Science, Number 30, 2006
[4] M.Ya.Goykhman et al. "Study of the mechanism high-temperature curing of polyimide ITA
binders". Acta Montana, Series B , No 7 (1997) 9-19.
[5] Invention with the patent № 2340968 «Method of immobilization for long-lived radionuclides»
Patent holder - PNPI RAS (RU). Patent Application № 2007105656. Priority from February
14, 2007. Registered in State register Russian Federation at December 10, 2008. Period ofvalidity February 14, 2027. Authors: Abdulakhatov M.K., Bartenev S.A., Goikhman M.Ya.,
Gribanov A.V., Guselnikov V.S., Zykov M.P., Firsin N.G.
[6] ASTM Standard. C 1220-92, Standard Test Method for Static Leaching of Monolitic Waste
Forms for Disposal of Radioactive Waste[7]. ASTM Standard. C 1285-94, Standard Test Method for Determing Chemical Durability of
Nuclear Waste Glasses: The Product Consistency Test (PCT)

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2.P11.
TECHNETIUM SULFIDES –ROLE IN CHEMISTRY AND ECOLOGY
German K.E., Peretrukhin V.F., Tumanova, D.N., A.Yu. Tsivadze
Institution of Russian Academy of Sciences A.N. Frumkin Institute of Physical
Chemistry and Electrochemistry RAS, Moscow, Russia, e-mail: german@ipc.rssi.ru

Keywords: technetium-99, sulphide, environmental chemistry,
Abstract
Sulfur is an element of high of high environmental importance, especially for understandingof many different metals behavior. Tc – S system is not an exclusion in this respect. The sulfur, itsdifferent compounds and their derivatives are often present in the natural waters, minerals and rocks
and being leached by dissolution mechanism or microbiological transformation affect drastically the
Tc environmental dissipation or concentrating routs. For better understanding the Tc behavior in the
different natural environments we need quantitive data for the composition and properties of Tc
sulfide species that could be formed. This review is aimed to analyze the progress in the field of TcS system with the principle focus to its environmental value.

Historical data and its reconsideration.
So-called technetium heptasulfide was among the first synthesized Tc compounds [1-2]because it was considered as a convenient route for Tc separation from aqueous solutions. Alreadyin the first works its composition was established as Tc2S7, thus supposing that Tc is present in its
higher oxidation state. This experimental data were sufficiently precise although rather surprising inview of Tc(VII) redox potentials being in contradiction with those of S2-. Spitsyn and Kuzina in
IPCAS, Moscow, as well confirmed this composition [3]. Meanwhile the crystallographic
characterization of technetium heptasulfide was not possible as the precipitate was completely Xray amorphous. All the attempts of recrystallization in solution failed and no explanation of thecomposition and the structure was available for more than 45 years [4].
Lee and Bondietti in 1979-83 studied the effects of Fe(II) and of S2- on Tc solubility having
found out that, in the absence of S2-, the pertechnetate was reduced by Fe(II) and Tc(IV) hydroxide
precipitated from the solution [5-6]. Meanwhile, in the presence of S2-, Tc2S7 precipitated, and theauthors concluded that Tc(VII) was not reduced with this ion [6]. When both Fe(II) and S2- were
present, Tc was reduced and coprecipitated with a FeS phase as a carrier.
Amorphous Tc(IV) sulfide was also described by Boyd having been prepared while heating
Tc2S7 in the absence of O2 [7]. Crystalline TcS2 in turn was prepared by chemical transport reaction
along a temperature gradient (1423-1353 K) in a sealed tube. According to [8] the presence halogen
as a carrier gas, improved transport efficiency [8]. This TcS2 formed triclinic crystals.
Sodium thiosulphate or thioacetamide were shown being able to produce Tc2S7 in treatmentof acidic Tc(VII) solutions [9, 10].
Important Tc accumulation by some sulfide minerals was observed [11-13], the mosteffective sorbents being the sulfides with higher solubility or possessing reducing metal ions. The
mechanism for Tc sorption differed for different minerals [13].
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The Tc2S7 solubility was investigated based on the measurements of Tc concentration in the
aqueous solutions equilibrated with the previously precipitated and washed technetium sulfide [13].
No reasonable value was possible to establish because of its complicated hydrolyses behavior under
the applied conditions as described in [3, 13] and references therein.
Formation kinetics was studied spectrophotometrically [14] providing with the data on the
Tc(VII) reaction with sulfide reaction while the further colloidal particle size speciation studies
supported with ultramicrocentrifuge technics [15-16] provided with the reliable information on Tc
concentration dependences.
The TcO4- and S2- solutions have important absorbances in the UV region, being completelytransparent in the region of visible light. In course of the reaction of the pertechnetate with S 2-, thebrown color of the solution develops, the corresponding spectrum being attributed to the technetium
sulfide formation [14]. For the kinetic studies in [14] the = 450 nm was chosen (Fig.1 – 2). Somekinetic curves registered for solutions with different with initial [TcO4-]0 , [Na2S] and pH are
illustrated at Fig. 2-4.

Fig.1. Typical spectrum for technetium sulfide formed
after exposition for t = 4560 s, in the solution with initial[TcO4-] 0 = 1*10-4 M, [Na2S] = 0,27 M and pH = 11,8.

Fig. 2. Kinetic curves registered at 450 nm for the reactionof pertechnetate with sodium sulfide: [TcO4-] 0 = (0,5 – 2)*10-4 M, [Na2S] = 0,27 M, pH = 11,8.

As the pH of the solution could be affected by hydrolyses and sulfide oxidation, some tests
were conducted in buffer solutions [14]. In all cases the pH was kept within pH = 8 – 12 region as
lover pH are favorable for hydrolyses of sulfide and hydrosulfide ions and conversion of elementarysulfur formed in the reaction into disulfide ion. The typical kinetics for phosphate buffers isdemonstrated in the Fig. 3.
Three stages are characteristic for this reaction, the first one being induction period (from13500 and up to 35000 s (= 9.7 h) dependent on the pH) its duration being dependent on the initialaccumulation of disulfide ion, the second – intermediate reduction of pertechnetate to mixed Tc
oxosulfide(V,IV) (14000 – 50000 s dependent on the pH) and the third – final formation oftrinuclear Tc disulfide [14-15]. The colloidal solutions of the technetium sulfide thus formed wererather stable. Similar solutions were described by T. Sekine and co-authers in [16]. The compositionof the precipitate separated from this solution by 10 kD ultramirocentrifuge membranes wasdetermined by chemical analyses and by Rutherford back scattering (CENBG Bordeaux-Gradingan
in collaboration with Lab. Pierre Sue, Saclay) and was equal to Tc:S = 2 : 6,73(25) [15]. This
precipitate was analyzed by EXAFS studies at ESRF, Grenoble the results (see Fig. 4.) had
confirmed its identity with the technetium sulfide studied by different authors [17-18].
The rate constant K1 for the initial step of Tc(VII) reduction with sulfide (producing Tc(IV)and polysulfide ions) was determined as 7.0.10-6 сек-1 while K2 constant for the final formation oftechnetium sulfide (in fact trinuclear technetium(IV) polysulfide) as shown in [17]) was 2.0*10 -4
сек-1, being by 2 orders of magnitude higher than К1.

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Fig.4. Tc K-edge EXAFS spectra (left) and their
Fourier transforms (right) of the Tc sulfide colloidal
solution corresponding to the reaction ofpertechnetate with sodium sulfide for [TcO4-]0 =2,0*10-4 M, [Na2S] = 0,27 M, pH = 11,8.

Fig. 3. Technetium sulfide formation kinetics(registered at 450 nm) in the reaction ofpertechnetate with sodium sulfide at constant pH
provided with buffer solution:[TcO4-]0 = 1.57*10-4 M, [Na2S] = 0.09 M,
buffer solution [HPO42-]/[H2PO4-] =3/1,[PO4] = 0,19 M, pH = 8.2

The influence of initial technetium(VII) concentration (within the range of (0,57-2,66)*10-4
М KTcO4 and constant [Na2S] = 0.3M) on the reaction rate of Tc and sulfide was determined fromthe data shown in Fig. 2 . The rate constant was practically lineary dependent on the technetium
concentration within the range (0,57 - 2,66)*10-4M.
The kinetics data recalculated from concentration to conversion degree axes are presented at
the Fig5. Under the listed conditions the reaction of Tc(VII) with sulfide was also characterizedwith induction period and the kinetics dependent on the [Na2S] in the solution and the pH of thesolution. Reaction of NaTcO4 with 0,3M Na2S was completed within 2000 s, the further
development of the precipitate was due to aging effects. The S/Tc ratio in the sediment was
obtained by chemical analyses as 3.36(7) on a macroammount of the precipitate and confirmed by
RBS (Fig.6) [15].
1,0
0,9

4

[Tc], *10 M

Conversion degree

0,8

Tc2.66
Tc1.9
Tc1.52
Tc1.14
Tc0.57

0,7
0,6
0,5
0,4
0,3
0,2
0,1
0,0

0

2

4

6

8

10 12 14 16 18 20 22 24
Time, minFig.5. Reaction kinetics of NaTcO4 with 0,3M Na2S ,pH=11.8, t=20oC [15].

Fig. 6. RBS determination of S/Tc ratio intechnetium sulfide [10]Particle growing processes were investigated for technetium(VII) sulfide (Tc2S7) colloids produced
in a mixture of Na2S and TcO4- solutions by laser-induced photoacoustic spectroscopy (LPAS).
Analysis of the LPAS signal intensities indicated that the particle size increased in the solution withan increase of standing time, while the number of particles remained constant. It was revealed thatthe size of colloid particles increased by deposition of Tc2S7 on the particle surfaces, not by
coagulation of colloid particles. The formation mechanism and growing process of the colloids are
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discussed based on the LaMer model, which deals with nucleation processes. In the aging processof Tc-S colloid system, the size of colloid particles was shown to increase by deposition of Tc
sulfide on the particle surface, not by coagulation of the particles [11].
The final ideas for explanation of Tc – S system became possible only based on EXAFS
studies [12]. It was demonstrated that -S-S- disulfide ligands are present in the structure thus
explaining the reduction mechanism for Tc(VII) to Tc(IV) with no notable change in Tc:S
stoichiometric ratio that remained close to the value within the interval of 3,3 – 3,5.

Fig.7. Structure unit fragment
Tc3S13 for technetium sulfide acc.
to EXAFS studies[17]Fig.8. Concentration of free Tc species as fractionized withseparation of ionic or nanocolloidal particles with 5 kD
“Sartorius” ultramicrocentrifuge tubes [15]At the same time the presence of S22- ligand in the compound explains some other properties
that was not well understood before. The determination of the concentration of free Tc species as
fractionized with separation of ionic or nanocolloidal particles with 5 kD “Sartorius”
ultramicrocentrifuge tubes [15] gave evidence on the Tc3S10 nanosulfide formation (Fig.3) similar
to that observed in [17].
0,0004C(Tc) = - 9*10-5Ln[Na2S] - 2*10-5
R2 = 0.99

C(Tc), M

0,00030,0002

Fig. 9. Solubility of Tc sulfide at
= 75 - 110 h as evaluated for
different [Na2S] by separation of
nano-colloidal particles with 5
kD “Sartorius”
ultramicrocentrifuge tubes [15]0,0001
0
0

0,2

0,4

[Na2S], M

The stability of Tc3S10 in the resulting solution was dependent of the S2- concentration in it. Whenhigher than 0.06M Na2S, further grouth of Ts sulfide particles occurred for  ≥ 150 h similar toobservations made in [11]. For [Na2S] ≤ 0.04 M, the Tc3S10 was reoxidized by present air to Tc(VII)within 175-200 hours thus being resolubilized.

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Fig. 10. The scheme of Tc reaction with sulfide describing precipitation and ultracentrifugal
speciation tests the follows the ideas drawn based on the results of Lukens et all. , Sekine et all and German
et all [15 - 17].

The determination of the free Tc species concentration with separation of ionic or nanocolloidal
particles with 5 kD “Sartorius” ultramicrocentrifuge tubes [10] (Fig. 4) gave evidence on the
Tc3S10+x nanosulfide formation similar to that observed in [12]. The equation for the Tc sulfide
solubility based on these figures was evaluated.
The stoichiometry of technetium sulfide precipitated from aqueous solutions by sulfide action wasrecently confirmed by Liu, Tery and Jurisson in [18]. Some important data on the FeS effect onto
Tc environmental behavior was reported by the same authors in [19]. Although the proposed
technetium dioxide formula applied in [19] for the processing of the EXAFS data differs in thenumber of water molecule bounded to the TcO2 from the recommended value (that is 1.6 H2O
according to [4], and very similar to 1.5 H2O observed earlier for Re(IV) hydroxide), the results of[18,19] support in principle the evidence for the formulation of common technetium sulfide
established by Lukens and co-workers [17]. Also the results of [20] are not in contradiction with[17]. Therefore we consider that the latter work provide a correct and important description oftechnetium sulfide is the compound is formed from water solutions by reaction of pertechnetatewith sulfide\polysulfide source.
Acknowledgments:
The work was carried out in part as the statutory work of the A.N. Frumkin Institute of Physical
Chemistry and Electrochemistry of RAS within the grant No.8 with the Department of Chemistry
and Material Sciences (Russian Academy of Sciences). We also highly acknowledge the fruitful
discussions with Dr. W. Lukens and the provided supplementary EXAFS and XANES data on
Tc3S10.
References.
1. Cobble, J. W., Nelson, C. M., Parker, G. W., et all., J. Am. Chem. Soc., 74 (1952) 1852.
2. Rulfs, C. L., Meinke, W. W. J. Am. Chem.Soc., 74 (1952) 235–236.
3. Spitsyn, V. I., Kuzina, A. F., “Investigation of weighable amounts of technetium”, Proc.
Acad. Sci. USSR Chem. Sect., 124 (1959) 103–105.
4. Rard J.A., Rard M.H., Anderegy G., Wanner H. // "Chemical Termodynamic of
Technetium.", by Ed. Sandino M.C.A., Osthls E., OECD NEA, Data Bank , Issy-lesMoulineaux, France, 1999
5. Bondietti, E.A., Francis , C.W. Science, 203 (1979) 1337-1340.
6. Lee, S. Y., Bondietti, E. A., In: “Sci. Basis Nucl. Waste Manage. VI, held Nov. 1982 in
Boston”, (Brookins, D. G., ed.), New York: North-Holland, 1983, pp. 315–322.
7. Boyd, G. E., “Technetium and promethium”, J. Chem. Educ., 36 (1959) 3–14.
8. Wildervanck, J. C., Jellinek, F., “The dichalcogenides of technetium and rhenium”, J. LessCommon Met., 24 (1971) 73–81.
9. Eckelman, W. C., Levenson, S. M., “Radiopharmaceuticals labeled with technetium”, Int. J.
Appl. Radiat. Isot., 28 (1977) 67–82.
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10. Anders, E., The radiochemistry of technetium,Washington D.C.: Department of Commerce,
1960, 50 p.,
11. Winkler A., Bruhl H., Trapp, Ch., Bock W.D. Radiochim. acta , 44/45 (1988), 183-186.
12. K.E. German, V.F. Peretrukhin, L.I. Belyaeva, O.V.Kuzina. In: "Technetium and Rhenium
Chemistry and Nuclear Medicine 4, (Bressanone-Bolzano-Italy, Sept. 12-14, 1994, (Nicolini
M., Bandoli G., Mazzi U.- Eds.) SGEditoriali, pp. 93- 97
13. S.El-Waer, K. E.German, V. F.Peretrukhin. J. Radioanal. Nucl. Chem., 157 (1992) 3–14.
14. M. Simonoff, K. E. Guerman, G. Simonoff. In: Abstracts of the 2nd Japanese-Russian
Seminar on Technetium, Shizuoka, 1999, p. 25
15. M. Simonoff, K. E. Guerman, C. Sergeant et all. Journee Radiochimie 2000, Gif-surYvette, 28-29 September, 2000, France.
16. Y. Saiki, M. Fukuzaki, T. Sekine et all. J. Radioanal. Nucl. Chem. 255 (2003) 101–104.
17. W. W. Lukens, J. J. Bucher, D. K. Shuh, N. M. Edelstein. Environ. Sci. Technol., 39(2005) 8064-8070.
18. Y. Liu, J. Terry, S. Jurisson. Pertechnetate immobilization in aqueous media with hydrogensulfide under anaerobic and aerobic environments. Radiochimica acta. 95 (2007) 717 - 727.
19. Y. Liu, J. Terry, S. Jurisson. Pertechnetate immobilization with amorphous iron sulfide.
Radiochimica acta. 96 (2008) 823-833.
20. M.J. Wharton, B. Atkins, J.M. Charnock, F.R. Livens, R.A.D. Pattrick, D. Collison. An Xray absorption spectroscopy study of the coprecipitation of Tc and Re with mackinawite(FeS). Applied Geochemistry 15 (2000) 347-354.

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2.P12.
TECHNETIUM LIMNOLOGY AS FRAME FOR ITS ECOLOGY AND THE
KEY FOR UNDERGROUND STORAGE
K.E. German, T. V. Khijniak, V.F., Peretrukhin
Institution of Russian Academy of Sciences A.N. Frumkin Institute of Physical
Chemistry and Electrochemistry RAS, Moscow, Russia, e-mail: german@ipc.rssi.ru
Winogradsky Institute of Microbiology of RAS
Prospect 60-letiya Oktyabrya 7/2, Moscow, Russian Federation

Radionuclides’ accumulation by natural associations of microorganisms is important item forcomprehension of their behavior in natural and technogenic water ecosystems. Different
microorganisms are shown to exhibit different concentration factors from very low to very high,and the situation is complicated when we analyze the behavior of natural sediments composing of
the association of some about 100 microbial species with some mineral. Tc transfer factors fromwater to sediments were analysed in some works [1-3 and ref. therein].The influence of natural
water composition onto radionuclides sorption by lake sediments is not thoroughly studied.
Here we overview the results of model laboratory study of the bioaccumulation of the longlived radionuclides [4-5]. The isotopes were introduced as pertechnetate solution (99Tc (VII)) or
nitrate solution ( 234Th (IV) - as a tracer for typical behavior of four-valent actinides) into batch
samples containing lake water and sediments taken from the 3 eutrophic lakes 1) Beloye Kosino(Moscow reg.), 2) l. Kezadra and 3) l. Navolok, both - Udomlya reg., near from Kalininskaya NPP).
The initial concentrations of Tc have been adjusted to 10-6-10-7 M and that of 234Th (IV) to 3000
cpm per initial aliquote. Eutrophic lake Beloye Kosino sediment was mainly formless organic
detritus, gray colored, H2S odoriferous. Udomlya reg. lakes sediment were 30% organic detritus andhumics, 60% sand and 10% (Fe2O3 and other inorganic minerals).
Table.1. Main eutrophic lake Navolok sediment and water phase content
Cells’
Comments
Microorganism
numberRatio in batch: Vsediment : Vliquid = 1:3
N/ml
Microalgae
106
Total = 2*109 bacteria/g,
Bacteria:
4
pH = 7.0 (stable);
Sulphate reducing
1045
Eh = -0.20V NHE (inner sediment part);
Methanogenic
10 – 10
water phase: [HCO3- ] = 1 – 4 mg-C/l;
Nitrifying
103 - 104
[HSO4-] = 0 – 50 mg/l, [Cl-] = 35 mg/l.
Denitrifying
105

Two equilibration modes were modeled (overhead agitation and hipolimnionic Tc transfer tosediment). Centrifuge MPW-210 (48G, 15 min), and microfilterfuge tubes – (5 kD “Sartorius” )were used for phase separation. No more than 5 % of water phase was sampled during theexperiments in total. More than 95% of Tc-99 were truly dissolved species of TcO4- in water phaseall time through the experiment. The kinetics’ analysis of data from Fig.1 has shown that the halftime values of the initial content removal from the water-phase form 400h for Tc. Two different
uptake rates were characteristic for Tc sorption for some samples from Udomlya reg. : fast uptake
during the first 2 hours when 40% of initial input was sorbed by eutrophic river/lake sediment, anda slow bioaccumulation period when Tc uptake was completed in 11 days.
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Fig.1. Tc uptake by Lake Sediments: O – steril
sample; -Torfyanoe,  - Beloe; white points sedimentation; black points – agitated inoverhead

Fig.2.Tc uptake by Lake Sediments A1 – steril
sample; K1 – Kezadra, N1- Navolok; H1Homutovka

The Tc uptake rate differed for different lakes sediments, the time of half-uptake being ½
month for eutrophic lake Beloye Kosino (Moscow reg.) and much less (4-7 days) for the two lakesof Udomlya reg. Concentration factors at 1600 hours of equilibration of Tc with sediments andnatural water were 1710 ml/g for eutrophic lake Beloye Kosino and 1850 ml/g for the two lakes of
Udomlya reg. The complete Tc accumulation by sediment took place after 1.0 months and 0.8
month respectively. Speciation by centrifuging at 10000 rpm, ultrafilterfuging or filtration through0.05 - 0.22 m membranes, has shown that the Tc fraction remaining in water phase was present as
truly ionic species up to 90%. The microflora of lake played important role in the accumulation andreduction of radionuclides. Some microorganisms (being able of anaerobic respiration) had
competition relationships between SO42- or NO3- and TcO4- so that the additions of SO42- or NO3decreases the rate of Tc accumulation by the sediment.
Reduction of Tc(VII) to Tc(IV) and sorption of hydrolyzed species are the main
mechanisms for Tc accumulation in this biosystem. We suppose that Tc(VII) reduction and further
uptake by the lake sediment is due to microbial activity of the sediment components, most probably
to sulfate-reducing bacteria, that are known to reduce Tc(VII) [5]. The difference in the uptake rateis associated with the higher chemical stability of TcO4-. This mechanism is supported by Tc uptake
rate slowing down when concurrent anions like sulfate or nitrate are injected into the water phase.
The sediments from freshwater lakes have a considerable sorption capacity. The
consecutive sorption runs have demonstrated only small decrease of Tc uptake rate. The desorptionof technetium was carried out with H2O, 1M HCl, 1M NaClO4 or 15% H2O2 and gave thedesorption factors of 0.05, 0.05, 0.08 and more 0.99 thus indicating the oxidative stripping
mechanism and contrary - the bioreduction of technetium to be the main mechanism of its uptake.
Thorium (IV) uptake by the sediments of both types was complete in 3 to 5 hours due tomuch more important sorption affinity of four-valent elements. About 20 % was sorbed by
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microparticulated organic matter and were removed only by microfilterfuge tubes ultrafiltration (5kD “Sartorius”).
The analyses of the new experimental results and its comparison with the literature data
unambiguesly indicate that some important ideas well developed in conventional limnology could
be applied with success to the modeling and the forcast of radionuclide migration in the mixed
mineral-sediment-aquatic natural environment both surfacial and deep underground. The known
dependencies of season variations of temperature, oxic conditions and hydrodynamics could be
usefull for these purposes. Some chemosynthetic and thermophilic bacteria species impact could be
discussed also with respect to the recent accidents at the seaside environments (p.e. Fukushima
accident).
References
1. M.J. Keith-Roach, P. Roos. The transport of Tc to the sediments of stratified fjords. Int.
Conference Migration’2001.Bregenz, Austria, Sept 2001. Abstracts, PA5-05
2. Blaylock B.G., Frank M.L., Hoffman F.O., Deangelis D.L. Behaviour of technetium infresh-water environment. In: Technetium in Environment. Edited by G.Desmet,
C.Myttenaere. Elsevier Applied Science Publishers. London, New York, 1986, p.79-90.
3. G.M. Milton, R.G. Cornett, S.J. Kramer, A. Vezina. The transfer of iodine and technetiumfrom surface waters to sediments. Radiochimica acta, 58/59 (1992) 291-296. .
4. Lloyd, J. Khijnyak T.V., Macascie L., and Lyalikova N.N. Reduction of technetium byDisulfo-fibrio desulfuricans: Biocatalyst Characterisation and use in a flowthroughbioreactor. Appl. Environm. Microbiol.1999, v.65, No.6. pp.2691-2696.
5. Guerman K.E., Khijnyak T.V., Peretroukhin V.F., German E.S., Firsova E.V. Behaviourof technetium in eutrophic and dystrophic fresh water lakes. The second Japanese-Russian
Seminar on Technetium. Shizuoka, Japan, Nov. 29 - Dec.2. 1999. Abstracts, pp.50-51.

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2.P13.
KASSITERITE AS A DURABLE HOST-PHASEFOR TECHNETIUM IMMOBILIZATION
Yu.I. Korneyko, V.M. Garbuzov, B.E. Burakov.
V.G. Khlopin Radium Institute, 194021 Russia, Saint-Petersburg,
2nd Murinsky Avenu, 28,e-mail : yuliakorneyko@mail.ru

Kassiterite, SnO2, is well-known accessory mineral with high mechanical and chemical
durability.
Solid solution of Tc in kassiterite, (Sn,Tc)O2, was suggested as a durable host-phase fortechnetium immobilization. Starting precursor was obtained by co-precipitation from aqueous
solution (SnCl2 + KTcO4) using ammonium hydroxide.
Reduction of Tc valence state from (7+) to (4+) was observed during precursor preparation.
Then precursor was calcined in air at 800°C, ground in agate mortar and cold pressed. Ceramic
synthesis was carried out at 1100°C in argon.
No essential evaporation of Tc was detected during synthesis.
Crystalline ceramic doped with 5% wt. Tc was obtained. All the samples obtained werestudied using optical and scanning electron microscopy (SEM); powder X-ray diffraction (XRD)
and microprobe analysis (EMPA).
Ceramic physical and chemical properties are discussed.
It was concluded that Sn-Tc-containing precursor obtained in air might be used for synthesisof Tc-doped ceramic based on kassiterite.
This is in contrast with all other precursors obtained before in reducing or inert atmosphere
only.

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2.P14.
ELECTROCHEMICAL INVESTIGATION OF CORROSION AND
DISSOLUTION OF METALLIC TECHNETIUM AND
Tc-Ru ALLOYS IN 0,5 – 6,0 M HNO3
A.G. Maslennikov1, K.V. Rotmanov2, N.G. Kravchenko1, V.M. Radchenko2,
M.V. Kormilitsyn2, V.F. Peretrukhin1
1
2

A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS

Joint Stock Company “State Scientific Center – Research Institute of Atomic Reactors”, Dimitrovgrad, Ulyanovsk
region, ryabinin@niiar.ru

The electrochemical oxidation of metallic technetium and Tc-Ru alloys in 0,5 – 6,0 mol/l
HNO3 was studied. The quantitative characteristics of the corrosion and dissolution processes were
determined.
It was found that at the concentration of the nitric acid in the electrolyte less than 2,0 mol/l
and at potentials less than 650 mV / Ag/AgCl the metal surface is passivated due to the formationof the slightly soluble hydrated Тс(IV) dioxide. The potential increase leads to the transition of thetechnetium metal into the transpassive state. In solutions containing more than 2,0 mol/l HNO3
hydrated Tc(IV) dioxide looses its passivating properties.
It is shown that oxidation of Тс(IV)/Tc(V) is the main reaction that effects the corrosion rate.
The results of the corrosion rates obtained from the measurements suggest that technetium metal
can be quantitavely dissolved in nitric acid if its concentration exceeds 4,0 – 6,0 mol/l.
Comparison of the repassivation potentials of Tc-Ru alloys with the repassivation potentials
using the pure Тс and Ru electrodes shows that the values of the alloy repassivation potential areintermediate between the repassivation potentials using the pure Тс and Ru electrodes. As in thecase with pure metals, the values of the alloy repassivation potentials increase with increasing the
HNO3 concentration in the solution.

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2.P15.
Tc-99 DETERMINATION IN CONTAMINATED GROUNDWATER
R.A.Aliev1, S.N. Kalmykov1, I.G. Tananaev2, I.A. Ivanov3.
1- 1 Lomonossov Moscow State University,(Leninskie gory, 1, Chem. Dept., Moscow, Russian Federation)
2 - Institution of Russian Academy of Sciences A.N. Frumkin Institute of Physical
Chemistry and Electrochemistry RAS, Moscow, Russia,
3 - PA Mayak, Ozersk, Russia

As a result of long-term operation of industrial ponds V-9 and V-17 as reservoirs for liquid
nuclear wastes at PA “Mayak” the significant contamination of groundwater system byradionuclides occur. During several years the distribution and migration of 90Sr, 137Cs, 60Co,
3
H and long-lived alpha-emitting isotopes in subsurface horizons was studied while no data
is available concerning the behaviour of 99Tc. This study presents the first experimental
results on 99Tc distribution in groundwater near V-9 and V-17 reservoirs. The samples werecollected from different depths.
The analytical determination of 99Tc included precipitation of Fe(III) hydroxide to coprecipitate some of the interfering radionuclides that form cationic species, then technetium
was reduced to Tc(IV) by adding Fe(II) and co-precipitated with its hydroxide. The
precipitate was separated by centrifugation and then dissolved in diluted nitric acid withaddition of H2O2 to oxidize Fe(II). Finally technetium containing solution was purified byanion exchange. The radioactivity of 99Tc was determined using liquid scintillation
spectrometry, the chemical yield was determined using 99mTc tracer.
It is shown that 99Tc activity varies between 1 and 2300 Bq/l with the tendency of increaseof its concentration with depth. The last fact could be explained by the high density of waste
solutions in V-9 and V-17 and gravitational exclusion of groundwater by contaminatedsolution.

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2.P16.
SORPTION OF Tc-99 AND Np-237 BY DEPLETED UO2
O. Batuk1, S.N. Kalmykov 1, E.V. Zakharova2.
1

Lomonossov Moscow State University, (Leninskie gory, 1, Chem. Dept., Moscow, Russian Federation)
2 - Institution of Russian Academy of Sciences A.N. Frumkin Institute of Physical
Chemistry and Electrochemistry RAS, Moscow, Russia

Alteration of spent nuclear fuel (SNF) upon storage in deep geological repositories under oxidizing
conditions will likely result in formation of secondary phases on UO2 surface. This may influence
the solubility of SNF and release of radionuclides to the environment. On the other hand
precipitated phases may limit the leaching of other radionuclides and prevent SNF from furtheroxidation. The goal of this work was the study solubility, secondary phase formation and Np(V)retention on the surface of UO2+x sample during hydrothermal treatment in simulated oxic
groundwater.
The UO2 sample was characterized by X-ray powder diffraction (XRD) and X-ray photoelectron
spectroscopy (XPS) to determine bulk and surface phase composition that were UO2 and UO2.25
respectively. The hydrothermal experiments were performed at 25C, 70C and 150C during 6
months in the presence of about 1·10-5 M of Tc(VII) and Np(V). For room temperature experiments
the retention of Tc(VII) Np(V) by UO2 sample was also studied as a function pH in batch mode.
Solid phase and solution aliquots were taken periodically for various analyses: determination oftechnetium and neptunium concentrations in solutions, for XRD, XPS, SEM and TEM analyses ofsolid phases. Neptunium sorption was almost quantitative for all studied temperature conditions
after one week of equilibration while technetium sorbed only at pH<2. Uranium solubility increasedin time and reached the equilibrium values typical for U(VI) also in about one week. The
progressive oxidation of the sample with formation of U(VI) alteration phases were detected by
XPS, XRD and TEM for samples treated at 70 0C and 150 0C.
For Np sorption experiments that were done at room temperature the reduction of Np(V) to Np(IV)was observed at pH<4.5 while technetium stayed as Tc(VII) that explains its low sorption affinity
towards UO2+x. Neptunium reduction was possible either due to its interaction with the surface that
had a shoichiometry close to UO2 at low pH as determined by XPS or through the reduction by
U(IV) present in solution. Upon the increase of pH the UO2 surface became more oxidized and its
stoichiometry became close to UO2.25 as determined by XPS. At pH>4.5 neptunium was present inpentavalent and was sorbed by the surface complexation mechanism.
The work was partly supported by the ISTC project No. 2694.

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2.P18.
ReO4- AND TcO4- ION-SELECTIVE BUBBLE-THROUGHFLOW CELLS
Yu.I. Urusov 1, K.E.German 2, A.V.Kopytin 3, A.F.Zhukov 1
1

D.Mendeleev Russian Chemical-Technology University, Miusskaya sq.9, Moscow, 125047, Russia
Frumkin Institute of Physical chemistry and electrochemistry, Leninsky pr.31-4, Moscow, Russia
3
Kurnakov Institute of General and Inorganic Chemistry Leninsky pr.31-1, Moscow, Russia

2

Keywords: Flow system; Bubble-through flow cell; Chloride; perrhenate; pertechnetate;
Ion-selective electrodes.
Abstract
A fast-response flow cell with ion-selective electrodes was constructed for continuous-flow
measurements in air-segmented streams without debubbling. The flow system was optimized
for perrhenate and pertechnetate determinations. With a flow-rate of 4 ml min -1 a sampling rateof 480 h-1 was achieved for ion determinations; the average relative standard deviation in all
instances was better than 3%. In order to eliminate the operation of removing bubbles withdebubbler and to obtain the rapid sampling rates in conventional air-segmented system, bubblethrough flow cells without different bubble-gating methods have been proposed in this report for Tc
and Re tetraoxometallate anion determination.
Introduction
The object of present work is a development and an investigation of ion-selective
electrodes for ReO4- and TcO4- determination in flow continuous analysis. As electrode active
substances in ion-selective electrodes were used quaternary alkylammonium salts.
Quaternary alkylammonium and phosphonium salts are widely used for preparation of themembranes giving a response to different ions. The selectivity of ion determination depends on
hydration energy of ion and on the nature of membrane solvent.[1] With this approach to a creationof new ion-sensitive sensors some electrode membranes for different anions and acidocomplexes
determination have been developed [ 2-5 ].
The system with the rotary valve was used for studying the dependence of the cell responseon the flow-rate.[ 6]Experimental
Membranes preparation. The ionophore ((С12Н25)4NReO4), plasticizer (onitrophenyloctyl ether, Fluka) and high molecular weight polyvinylchloride (Aldrich) weredissolved in the appropriate volume of cyclohexanone and mechanically stirred. All membrane
cocktails were cast in glass rings placed on glass plates. Solvent from PVC membrane wasallowed to evaporate at room temperature. The thickness of the resulting membranes was about 0.2- 0.3 mm.
The electrochemical properties of the electrodes were investigated in the conventional
configuration. Small disks were punched from the cast membranes and mounted in electrodebodies. The external reference electrode was a double-junction Ag/AgCl reference electrode OP8020 P (Radelkis). The potential was measured using pH/ion analyzer OP-300 (Radelkis, Hungary).
Potassium perrhenate (pertechnetate) solutions in 1M Li2SO4 were used for the electroderesponse function determination. The selectivity coefficients were determined by the separate
solution method (SSM) using 0.01 M potassium or sodium salts of the anions.
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The influence of pH on the electrode response was examined by adjusting the pH of themeasured solution with 1M sodium hydroxide and hydrochloric acid.
Flow cell construction
All the measurements were done with a flow cell of modified wall-jet design (Fig. 1).

Fig. 1. Bubble-through flow cell. (1) Cell body; (2) membrane; (3) ion-selective electrode; (4) steel
spring; (5) inner reference solution; (6) sample guide.
The body of the cell is fabricated from a Plexiglas cylinder, 5 cm in diameter and 2 cm long. Two
Teflon sample guides are screwed into the bottom of the cell body, each having a narrow inlet channel(0.4 mm in diameter). The indicator and reference electrodes are supported in a vertical position bysteel springs serving also as connecting wires for the mV/pH meter. The electrodes rest on the flat
top surfaces of the sample guides, the diameter of sensing membranes being equal to that of thesample guides (5 mm). To reduce the pressure built up in the system, supporting springs are adjusted
so that the electrodes rest on the surface of the sample guides with 1-3 g force. The electrodes are
positioned so that the flow is introduced at the centre of the membrane face and is forced to exit
between the membrane face and the top surface of the sample guide around the membrane perimeter
into the reservoir. The liquid level in the reservoir is kept constant (ca. 0.5 mm above the membranesurface) by differential pumping. Air bubbles passing quickly between the membrane face and thesurface of the sample guide never collect under the membrane covering the whole sensing surface, so
the contact between indicator and reference electrodes is never broken. Reference electrode on thebasis of a composition of Ag2S-AgCl was used.
Apparatus
A Reihelt E 25/WM K10 peristaltic pump was used for pumping the solutions. The sampler wasContiflo OL-601/11 with a laboratory-made programming device, allowing different sampling rates
and sample-to-wash ratios to be maintained. The potentials were measured at room temperature witha Radelkis OP-208 pH/mV meter and recorded by an x-t recorder. Tygon tubing (0.7 and 1.65
mm i.d.) was used to construct the manifold.
A schematic diagram of the cell response rate measuring system is shown in Fig. 2.

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Fig. 2. Schematic diagram of the cell response rate measuring system. (P) Peristaltic pump; (V) rotary
valve; (D) flow cell; (M) mV/pH meter; (R) x-t recorder; (1), (2) standard solutions, flow-rate 1-12
ml min-1; (3) reference solution, flow-rate 2 ml mi n 1 ; (4) to waste, flow-rate 14 ml min-1.
A Teflon rotary four-way valve was used to interchange the solutions flowing through the cell. The
channels of the valve were 0.8 mm i.d.; the inlet port of the cell was connected to the valve outlet port
by a 1-cm length of 0.76 mm i.d. Tygon tubing. With manual operation of the valve, sharp
concentration jumps were obtained; in any event the dispersion of the solutions was kept constantthroughout all the measurements.
Figure 3 shows a schematic diagram of the automated analysis flow system. The analyzer includes
no special devices for either the air segmentation (air-bar) or the debubbling.

Fig. 3. Schematic diagram of the automated analysis flow system. (P), (D), (M), (R) as in Fig. 2; (T) Tconnector; (C) mixing coil; (S) sampler; (1) air, flow-rate 2.6 ml min-1; (2) buffer solution, flow-rate 2
ml min-1; (3) sample/wash, flow-rate 2 ml min-1; (4) reference solution, flow-rate 2 ml min-1; (5) wash
(distilled water), flow-rate 3 ml min-1; (6) to waste, flow-rate 7.5 ml min-1.
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Results and discussion
The response for ReO4- and TcO4- electrodes are shown in fig.4.

Fig.4 Responses ReO4- and TcO4- selective electrodes.
For all these electrodes response function is linear in the range 10-6 - 102 М with the slope equal to59±2 mV/pTc at 25°C.
Almost the same results have been obtained with tetradodecylammonium
perrhenate (pertechnetate).
High potentiometric selectivity to ReO4- and TcO4- of the ISEs against the main anions wasfound for all the ISEs developed (see Table 1).
Table 1. Selectivity of ReO4- and TcO4- electrodes.
ionelectrode

F-

SO42-

H2PO4-

Cl-

NO3-

BF4-

ClO4-

TcO4-

ReO4-

ReO4-

2.10-5

3.10-5

1.10-5

1.10-49.10-4

7.10-2

0.1

1.2

1

TcO4-

1.10-5

3.10-5

9.10-6

1.10-4

1.10-3

6.10-2

0.1

1

0.9

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Fig.4. Dependence of time of the response on speed of submission of a solution
1. 1.10-2М → 1.10-4М ; 2. 1.10-4М → 1.10-2М
Cell response rate
The system with the rotary valve (Fig. 2) was used for studying the dependence of the cell responseon the flow-rate.The cell response time т90, the time to reach 90% of the steady-state potential for both
the ReO4- and TcO4- electrodes, was observed to improve when the flow-rate was increased in therange 1-7 ml min-1, as shown in Fig. 4
Further increases in flow-rate had no significant effect on the cell response time; a flow-rate of 4
ml min-1 was chosen for operation of the automated analyzer. The increase in a range of determined
concentration leads to increase in a relative standard deviation.(fig. 5)

Fig. 5. Dependence of a relative standard deviation on a range of determined concentration
Automated analysis
The mixing coil dimensions and the air flow-rate were optimized during preliminary experiments.
Ten turns of a 50-cm length of glass tubing with i.d. 1.5 mm were sufficient for adequate mixing of thetwo streams, each having a flow-rate of 2 ml min-1. Changes in the air flow-rate from 2 to 3 ml min-1
had no effect on the noise level and the sample dispersion; an air flow-rate of 2.6 ml min-1 was chosen
for operation of the analyzer.
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Mixing between the sample and the wash slugs as they pass through unsegmented zones of the CF
system, i.e., from the tip of the sample probe through the pump to the T-connector, contributes
considerably to the dispersion in the flow system. To reduce this mixing effect in the sample line, theintroduction of two air segments at the leading edge of each sample and wash slug by rapid repetitive
insertion and withdrawal of the sample probe ("pecking") was used [7]. This pecked samplingtechnique significantly reduced carry-over and allowed the sampling rate to be increased.
With ion-selective electrodes used in flow analysis, the wash (or carrier) stream electrolyte isusually spiked with the ion to be measured to stabilize the baseline and improve the response [8,9].
More often this is adopted when FIA is used, as a variable baseline may affect significantly therecorded peak-height value. When the CFA technique is involved, i.e., a steady-state or close tosteady-state detector signal is measured, the baseline is not always necessary. For the automateddetermination of ReO4- and TcO4- 1M Li2SO4 was used as the wash electrolyte; this reduced the cell
wash time and allowed the sampling rate to be increased.
For Ion determinations the sampling and wash times were 4 s, the sampling rate being 450 h-1. A
typical recording for the analysis of aqueous Ion standards is shown in Fig. 6. The percentage of thepeak height observed with respect to the peak height of the steady-state response (98-99%) is
acceptable when the CFA technique with ion-selective electrodes is used [10-12]. The calibrationgraph is linear in the concentration range employed (0.001-0.0001 M) and has a slope of 59 mV,
which did not change during 3 months of continuous use.
For ReO4- and TcO4- determinations the sampling time was 3.5 s and the wash time was 4 s, thesampling rate being 480 h-1. Calibration runs and analysis standard samples for ReO4- are shown in
Fig. 7.

1
2
3
Fig.7. Renium determinations in standard solutions.
(1) A series of steady-state measurements (10-4-10-3 M);(2) calibration runs;(3) sequential analysis of aqueous standards containing 10-3 and 10-4 M.
The calibration graph is linear in the concentration range used (0.0001-0.001 M) with a slopeof 57.5 mV. The average relative standard deviation in all instances was better than 3%.
Changing the analyzer operation mode from ReO4- and TcO4- determination took less than 5min, involving only sampler reprogramming and replacement of electrodes and reagent bottles.
As an increase in the sampling rate is an important factor, this work was intended to demonstrate,using a simple example, the possibilities of the air-segmented technique and its advantages (higher
sampling rate with simpler equipment) compared with the non-segmented approach.
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Conclusion
Have been offered and studied electrodes for quantitative definition of ReO4- and TcO4-.
Electrodes can be applied to the analyses of ReO4- and TcO4- in some kinds of solutions flow
analysis. The system with the rotary valve was used for studying the dependence of the cell responseon the flow-rate.
References
1. N. Lakshminarayanaiah. Membrane electrodes. Academic Press. New York, San Francisco,
London. 1976.-360p.
2. Fu В., Bakker E., Yun J. H., Yang V.C., Meyerhoff M.E. Analytical Chemistry. 66, 2550
(1994).
3. T. Ito, H. Radecka, M. Kataoka, K. Tohda, E. Kimura, K. Odasima, Y. Umezawa. J. Am.
Chem. Soc. 120, №13, 3049 (1998).
4 A. Schwake, K. Cammann, A.L. Smirnova, S.S. Levitchev, V.L. Khitrova, A.L. Grekov, Yu. G.
Vlasov. Anal. Chim. Acta. 393,19 (1999).
5 Rakhimenko EM., Prilutskaya, Yakimenko T.M., Yakimenko O.V. II Proceedings of the
National Academy of Sciences of Belarus. Series of Chemical sciences, №1 (2000), 18-23.
6. J. Ruzicka and E.H. Hansen, Flow Injection Analysis, Wiley, New York, 1981.
7. C.J. Patton, M. Rabb and S.R. Crouch, Anal. Chem., 54(1982) 1113.
8. K. Toth, J. Fucsko, E. Lindner, Zs. Feher and E. Pungor, Anal. Chim. Acta, 179 (1986) 359.
9. J. Ruzicka, E.H. Hansen and E.A. Zagatto, Anal. Chim.Acta, 88 (1977) 1.
10. M. Vandeputte, L. Dryon and D.L. Massart, Anal. Chim.Acta, 91 (1977) 113.
11. P.W. Alexander and P. Seegopaul, Anal. Chem., 52 (1980)2403.
12.Т.К. Christopoulos and E.P. Diamandis, Analyst, 112(1987) 1293.

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Re Hydrometallurgy

The chairman of the 3rd section I.D. Troshkina and G.S. Schteinberg

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3.1.
RHENIUM IN NUCLEAR FUEL CYCLE
I.D. Troshkina

D. Mendeleyev University of Chemical Technology of Russia,(Miusskaya Sq. 9, Moscow, Russian Federation)

Keywords: rhenium, nuclear fuel cycle, uranium mining, rhenium alloys, rhenium –188.

Nuclear-power complex, as is known, includes a number of some production cycles: the recovery of
uranium from mineral resources, production of its pure compounds by using its chemicalengineering, isotope enrichment, nuclear fuel production, fuel use in nuclear reactors to generatesteam and electricity, as well as work on disposal of radioactive waste.
This review covers the following areas of location and use of rhenium in the nuclear fuel cycle(NFC).
1. Rhenium recovery in uranium mining and hydrometallurgical processing.
2. Rhenium-containing alloys – structural material of high-temperature nuclear reactors.
3. Rhenium as isotope production for nuclear medicine.
4. Rhenium - a simulator of technetium in research investigations.
1. Rhenium recovery in uranium mining and hydrometallurgical processing. Implementation of
the first stage of the nuclear fuel cycle (NFC) – uranium mining at the present stage is accompanied
by a strengthening of the role of complex processing [1,2].
Rhenium, an important strategic metal, has a special place among the other by-product metals dueto the high profitability of its recovery. Rhenium is usually obtained mainly from molybdenum andcopper ores [1]. In 2009, production of primary rhenium was more than 40 tons. Nearly two-thirdsof the primary rhenium was made in Chile, the other major producing countries are the UnitedStates, Poland, China and CIS countries (Kazakhstan, Uzbekistan and Armenia). Data on the
primary and secondary production of rhenium, the deficit and surplus, stocks and demand from2000 to 2009 are presented in the Fig. 1.

Fig. 1. The dynamics of the rhenium global market [3].

Stocks are not available. Demand for rhenium is higher than supply. The annual consumption ofrhenium in 2015 will reach more than 70 t under the influence of demand in the production ofrhenium-containing alloys for the aerospace industry.
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Rapid increasing demand of rhenium superalloys is the reason of intensive processing of uranium
ores.
Background. For the first time rhenium was obtained from uranium ores in 1969 in the UnitedStates of America. Beginning about 1969, significant quantities of rhenium were recovered as byproduct of the uranium ores produced in the Falls City, Texas area by Susquehanna Corporation.
The rhenium was recovered in dilute solution and shipped by railroad tank cars to Shattuck
Chemical in Denver. There it was integrated into the Shattuck system for production of ammonium
perrhenate. Rhenium was obtained up to 1974 [4].
In the former USSR rhenium was first discovered in 1978 during the operation of uranium deposits
in Central Asia (Bukinayskaya group) in the productive solutions of underground leaching [2].
Increased content of rhenium is observed in uranium deposits of the sedimentary type, as well as
stratum-infiltration exogenous deposits. For example in the USA the rhenium content is (0,5 - 3,0g/t) for the ores of sedimentary deposit situated at the Colorado Plateau and up to 50 g/t for
stratum-infiltration molybdenum-grade uranium ores in the South Dakota.
Geochemical relationship of rhenium with uranium and molybdenum is the characteristic feature ofuranium ores. The rhenium in the molybdenum-uranium deposits of the exogenous type present asgeptaoxide.
In the former Soviet Union stratum-infiltration exogenous epigenetic deposits, developed aprogressive method of underground leaching, are concentrated within a few ore-bearing provinces:Central Kyzyl Kum, Syr Darya, Chu-Sarysu, Ili, which form the largest uranium province of theworld – Prityanshanskaya [2]. Ancient reservoir zone of oxidation and the associated uranium
deposits with associated Re-known in the Turan plate complex platform within Prityanshanskoy Uore province. First of all, it is well-known deposits of Kazakhstan and Uzbekistan.
An important feature of polymetallic ores is a distinct correlation to the power of rhenium anduranium, which allows to predict the content of rhenium reserves, using parameters of the uraniumore.
In accordance with a reserve of rhenium per unit area in the deposit plan (the productivity) rheniumuranium ores are divided into very poor (up to 1 g/m2); low-productivity (1-5 g/m2), ordinary (5-10g/m2) and high-yield (10 g/m2) [2].
Leaching. Uranium ore, depending on the composition of processed according to the schemes ofacid or alkali leaching.
Assessment of the underground leaching of rhenium can be made based on the results ofthermodynamic calculations of dominance fields of its compounds in the liquid and solid phaseswith separation of geotechnical regimes of selection (Fig. 2).

Eh, V

Fig.2. Fields of rhenium predominance(temperature - 25 oC, pressure - 1 bar, concentration of
sulfate-ions – 10-1 mol/l, concentration of carbon dioxide –10-1.5 mol/l, concentration of rhenium –10-5.8 mol/l) [2]:1 - fields of solid phases;
2 - fields of liquid phase;3 - geotechnological fields

Interaction of leaching solutions with rhenium
disulfide – the most likely compound of rhenium inuranium ores, occurs in accordance with the reaction
ReS2(solid) + 4.75 O2(g) + 2.5 H2O 
ReO4- (liq.) +2 SO42- (liq.) + 5 H+ (liq.).
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The nature of the medium does not affect on the thermodynamic characteristics of this reaction. It
requires the presence of oxygen or other oxidants to its implement. As can be seen from Fig.2,
sulfuric acid and carbonate with an oxidizer geotechnological environment, located in a vast field of
perrhenate ion are favorable for the leaching of rhenium. Under these conditions, rhenium can berecovered from ores with molybdenum and uranium. The special role of oxidant to convert rhenium
from a solid to a liquid phase was confirmed.
Using chemicals and produced water without oxidizer degree of recovery of rhenium does notexceed 20-30%; in the presence of oxygen, regardless of the type of agent (including the applicationof produced water) - 50-60% or more. The use of hydrogen peroxide in an amount equivalent to theoxygen concentration of 100-500 mg/l, increases the degree of recovery up to 70-95%. The average
concentration of rhenium in output solutions, depending on the initial content in the ore varied from
0.15 to 2.5 mg/l.
Comparison of the leaching kinetics of rhenium and uranium shows that rhenium is recovered firstfrom uranium ore (Fig.3).
Fig. 3. Diagram of uranium (1) andrhenium (2) filtration leaching by using
bicarbonate solution with oxidant [2].
Theammoniumbicarbonate
concentration – 2 g/l, the concentrationof hydrogen peroxide – 0.6 g/l, theinitial content of uranium in the ore –
0.5%,initial content of rhenium – 1 g/t.
εU, εRe – the degree of uranium andrhenium leaching, %.
Liquid: Solid
Anion resin AM-p after desorption
U = 0,5 kg/t

Elution of rhenium
Anion resin AM-p
To the sorption of U and Re (au = 0,1 kg/t)

Eluate cRe = 10÷15 mg/l

Extraction of rhenium (1 stage)
ε = 60 – 70 %extract

Fig. 4. The process flow
diagram of rhenium recovery
from uranium ore leachingsolutions [2].

Re

CRe = 300 mg/l

Water

O : W = 1 : 20

rinse water
to the process

Washing of the extractant

Duringsulfuricacid
leaching rhenium begins toactively move to thec = 1 g/l
solution, as soon as theextractant
raffinate
Extraction of rhenium (2 stage) [TAA – 32%; saturated alcohols oxidizing agent (including
O:W=1:510%; CVS (kerosene) – 58%]
extract
ε = 60%atmospheric
oxygenC = 8 g/l
introduced
tothereagent)
25% ammonia
Solid re-extraction of rhenium
reaches the ore.
O : W = 10 : 1
Recovery of rhenium isRecrystallization of NH4ReO4considered economically
Washing of NH4ReO4 by alcohol
feasibleforcomplexprocessing of ore to
Product NH4ReO4produce molybdenum.
The process flow diagram of rhenium recovery from uranium ore leaching solutions is shown in
Fig. 4.
O:W=1:1
extractant[TAA – 32%; saturated alcoholsBack extraction of rhenium
pH 1 – 2- 10%; CVS (kerosene) – 58%]
reextract O : W = 7 : 1

5 - 6 M ammonia

Re

Re

Re

The recovery of rhenium from solutions of underground leaching of uranium is carried out by
sorption method. Rhenium and uranium are sorbed from productive sulfuric acid solutions by
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011strong-base anion exchanger (for example AM-p or other [1,2,5,6]). Selective desorption ofrhenium is carried out by acidic solutions containing nitrate ions (NO3-– 80-90 g/l, HNO3 – 44.5%). Rhenium is extracted from the eluates (10-15 mg/l Re) by the solution of trialkylamine
fraction of C7-C9 in kerosene with the addition of decanol as a modifier. Content of rhenium in theextract is up to 8 g/l, which allows to carry out the back extraction of rhenium in solid form by theammonia solution.
Rhenium can be precipitated from the nitrate-sulfate eluates by water-soluble polyelectrolytes [7].
The sorption of rhenium with uranium anion exchangers AN-21 and AMP is observed from thebicarbonate solution. In this case, the sorption of uranium anions is completed much earlier thanrhenium. Applied to fields in the Northern Bukinay (Uzbekistan) scheme for processing ofbicarbonate solutions using an oxidant includes: sorption of uranium and rhenium anions; solidphase desorption by solutions of sodium bicarbonate and ammonium carbonate; selective
desorption of rhenium by ammoniacal solution of ammonium thiocyanate (1-2 mol/l NH4SCN + 1%
NH4OH), precipitation of crystals of ammonium perrhenate by evaporation of desorbate (at 80°C)[2].
Under the scheme of acid leaching slightly carbonate ores (mine Ambrosia Lake, Gas Hills, etc.) areprocessed. 1 ton of rhenium per year was produced from sulfuric acid solutions at all US refineries.
And the degree of rhenium recovery was 50%. Scheme of alkali leaching is used for processing ofhigh carbonate uranium ore (mine Ambrosia Lake, Front Reynd, etc.) [1].
For the associated extraction of rhenium from productive solutions of underground leachingalternative biological methods are developed.
Along with uranium and rhenium molybdenum, vanadium, selenium, yttrium, rare earth metals,
scandium can be recovered from multicomponent solutions of underground leaching. Sorption andextraction methods are developed for processing of these complex composition solutions [2].
For the recovery of rhenium from sulfuric acid solutions obtained by underground leaching, alongwith well-known, synthetic granular nanostructured styrene-acrylate resins of new generation havebeen successfully tested [8].
The complex processing of productive solutions can increase profitability mining of low-grade ores.
Despite the low value of the share price of rhenium in the product, significant amounts of recycled
productive solutions allow to get tons of rhenium. Since the basic and operational costs forunderground leaching include the cost of extracted principal components - uranium, the cost of
associated rhenium and other metals will consist of operating and capital costs for their recycling,which reach 10-15% of the cost of the final product. Indicative techno-economic calculation ofcomplex processing of productive solutions allows justify the concentration of rhenium in waste
solutions after sorption: when the initial concentration of rhenium is 0.2 mg/l, residual
concentration may be 0.1 mg/l. In this case, the profitability of extraction of rhenium is very high 540%, indicating the possibility of an effective recycling of solutions with lower initialconcentrations of rhenium.
2. Rhenium-containing alloys – structural material of high-temperature nuclear reactors.
Tungsten-rhenium alloys as structural materials of equipment operate at high temperatures (1000–
1200 oC). W-alloys are used as plasma facing components in fusion reactors [9]. Neutron irradiationinduces significant transmutation of tungsten into rhenium and osmium. Precipitation of thesealloying elements could dramatically modify the properties of the initial material. Using atom-probe
tomography, it was showed that neutron irradiation could trigger the precipitation of nanoscaleprecipitates of the σ and χ phases in W-10 and 25 at. % Re alloy irradiated between 575 and 675 oC
to 8.6 dpa (Fig. 5).

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Fig. 5. 5 nm thick slices through atom-probe tomography reconstructions obtained from a W-25 at. % Re
alloy. Only Re atoms are shown. (a) Re is in solid solution before implantation (a) and (b) clustered after
implantation by 2 MeV W ions at 500 oC to 2.8 dpa. (b) The concentration distributions confirm the random
Re distribution before implantation and non-random one after implantation [9].

More observations of precipitation in irradiated tungsten alloys revealed the onset of phaseseparation at low doses. Fig. 5 shows 3D reconstruction of a W-25 at. % Re alloy before and after
implantation revealing the formation of nanometer-scale Re-rich clusters after only 2.8 dpa at
500oC. Understanding of irradiation –induced precipitation in W alloys is still inadequate, in greatpart due to the lack of knowledge of the phase diagram. While the high temperature part of the WRe phase diagram predicts complete solid-solution up to 22 at. % Re, the lower part of the diagram(T<1500oC) cannot be assessed experimentally for kinetic reasons. Systematic atomic-scale
experimental and theoretical work may pave the way towards a better understanding. Precipitationof these alloying elements could dramatically modify the properties of the initial material.
Rhenium is intended for use in high-temperature nuclear power plants to improve efficiency andsafety of their work. The interaction of nuclear fuel − uranium mononitride with the material
cladding − rhenium in the temperature range 1800-2200K was investigated [5].
Rhenium-molybdenum alloy large tubing was developed for nuclear reactor control [5].
3. Rhenium as isotope production for nuclear medicine. Actively being introduced into medical
practice a generator of rhenium-188 is obtained from the stable isotope of tungsten-188 produced atenterprises NFC. Isotope of rhenium-188 is used in nuclear medicine for diagnostics of someillnesses [5].
4. Rhenium - a simulator of technetium in research investigations.
This field of Re using in NFC is connected due to the similarity of rhenium and technetium
properties. So rhenium substitutes technetium in the modeling process to generate predictions of thenuclear fuel cycle. However it should be taken into account that investigation of technetium
behavior in a variety of complexes in multicomponent NFC solutions cannot be always possible.
According to modeling method for creating predictions for the nuclear fuel cycle, proposed byInternational Atomic Energy Agency, rhenium can substitute technetium in solid products, forexample, in sludge.
Conclusions.
In the implementation of the nuclear fuel cycle traditional features of associated recovery and use ofrhenium are being saved:- As a trace element rhenium is extracted from uranium multicomponent raw materials.
As a metal, having high refractoriness, it is used in the heat-resistant alloys for the
manufacturing of high-temperature reactors.
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References.
1. A.A. Palant, I.D. Troshkina, A.M. Chekmarev, Metallurgy of Rhenium, Science: Moscow (2007).
298 p. (rus.)
2. In-Situ Leaching of Ores, Academy of Mining Sciences, Publishing House: Moscow (1998). 446
p. (rus.)
3. www.roskill.com/reports/minor-and-light-metals/rhenium, 2010.
4. Proceedings of the International symposium on rhenium and rhenium alloys: TMS annual
meeting. Orlando (Florida), 1997. 826 p.
5. 7th International Symposium on Technetium and Rhenium – Science and Utilization. Book of
abstracts. July 4-8, 2011, Moscow, Russia. 204 p.
6. A. Zagorodnyaya, Z. Abisheva, E. Ponomaryova, V. Bobrova, Non-ferrous metals. 8: 59 – 62
(2010).
7. A. Chekmarev, I. Troshkina, Y. Nesterov et al., Chemistry for Sustainable Development. 1 (11):113-117 (2004).
8. I. Troshkina, N. Balanovsky, A. Shilyaev et al., Chemical Technology. 6: 337-341 (2011).
9. E. Marquis, J. Hyde, D. Saxey, S. Lozano-Perez et al., Materialstoday. 12 (11): 32 (2009).

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3.2.
RHENIUM OF KAZAKHSTAN(REVIEW OF TECHNOLOGIES FOR RHENIUM RECOVERY FROMMINERAL RAW MATERIALS IN KAZAKHSTAN)
Z. S. Abisheva, A. N. Zagorodnyaya
Centre of Earth Sciences, Metallurgy and Ore Beneficiation (Shevchenko, 29/133, Almaty, Kazakhstan)

Keywords: rhenium, sorption, desorption, wash sulfuric acid, underground leaching solutions
Abstract:

Results of the study on sorption technology development for rhenium recovery from newcomposition of wash sulfuric acid solution from Kazakhstan copper smelter and from undergroundleaching solutions of Kazakhstan uranium deposit using А170 and А172 weak basic anionites (byPurolite) are presented in the paper. Effect of parameters typical for rhenium sorption anddesorption was studied. Optimum parameters for rhenium recovery were selected. It was shown that
good performance for rhenium recovery from the solutions could be achieved with use of A170
ionite only. Flow sheet are proposed for the solutions.
Introduction
Rhenium in Kazakhstan has been recovered as a by-product during copper and molybdenum
concentrate processing obtained from Kounrad, Sayak and Zhezkazgan ore deposits. The firstcommercial production of rhenium in Kazakhstan was organized in the 1940s originally frommolybdenite concentrate roasting dust and later from solutions of the trapping system and fromwash sulfuric acid solutions of metallurgical gas cleaner after electro-smelting and matte conversion
at the Balkhash copper smelter. In early nineties rhenium production was suspended due to lack of
raw materials, at the smelter. Currently, it is recovered only from wash sulfuric acid of theZhezkazgan copper smelter during Zhezkazgan copper ore concentrate processing. Also rhenium
partially goes to dust and slime transferred to the lead smelter. It should be noted that rhenium
containing lead and zinc concentrates are also produced from Zhezkazgan copper ore. Leadconcentrate and dust from copper concentrate processing are used at lead smelter along with otherlead-containing materials. During lead processing rhenium goes mainly to the dust and partially to
the wash solutions. A number of technologies have been developed for rhenium recovery from dustleach solutions and from gas clean solution.
Thus, processing of copper and lead concentrates produces rhenium-containing solutions, dust andslime. Commercial production of ammonium perrhenate from the solutions has been organized at
the copper and lead smelters. Technologies for rhenium recovery from the dust and the slime havebeen developed and tested at the smelters. Although quite good results were achieved during thetests the technologies were not implemented in commercial production due to some reasons.
In 2008, Balkhash copper smelter recommenced processing of Zhezkazgan copper concentrates andresumed sulfuric acid production. So, it is necessary to resume production of ammonium perrhenate
at the smelter. Previously sorption technology by the Institute of Metallurgy and Ore Concentrationof Kazakh Academy of Sciences (now Centre of Earth Sciences, Metallurgy and Ore Beneficiation)
was used. Since composition of the wash solutions now is different from the wash solutions of
1970th - 1980th and new anionites available in the market it is necessary to study rhenium recovery
from the wash solutions.
Kazakhstan uranium ore also contains significant quantities of rhenium. The ore is mined with useof underground leaching method. No rhenium recovery from such solutions has been undertaken
yet, despite some readily available technologies.
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The issues of rhenium recovery from wash solutions of copper and lead smelters and from uranium
underground leach solutions were presented at the symposium and also discussed in detail in the
publications [1]. In this paper we present the results of sorption technology development forrhenium recovery from wash sulfuric acid of different composition and from underground uranium
ore leach solutions using weakly basic anionites (by Purolite). Optimum conditions for sorption anddesorption were selected and principal technologies for rhenium recovery were developed on thebasis of the study.
Experimental
Reagents. Anionites: AN-21 (Russia), A170 and A172 (Purolite). Industrial wash sulfuric acidsolutions (WSAS) from Balkhash copper smelter (BCS), underground leach solutions (ULS) andfiltrates after uranium sorption (UF) from a KAZATOMPROM enterprise. Sulfuric acid (chemicallypure, GOST 4204-77); hydrochloric acid (chemically pure, GOST 3118-77); nitric acid (chemicallypure, GOST 4461-72); sodium hydroxide (chemically pure, GOST 4328-77); and ammoniumhydroxide (chemically pure, GOST 3760-64).
Pretreatment of ionites. Anionites were cleaned from iron and synthesis products using sodiumhydroxide and hydrochloric acid solutions [2]. The A170 anionite was converted into chloride,sulfate, hydrosulfate and nitrate forms under dynamic conditions according to the conventional
method [2] by washing it with 2 mol/dm3 solutions of the acids. To prevent hydrolysis ofhydrosulphate ions, the saturated anionite was washed with dehydrated ethanol until negative
reaction to sulfate ions is achieved. Transformation of the ionite in HSOˉ4 form into sulfate form
was made by washing of the ionite with water.
Methods of analysis. Rhenium in solutions was analyzed using atomic emission spectrometry (AES
Optima 2000 DV, PerkinElmer, USA) and in column effluents using colorimetric method [3].
Uranium was analyzed using method [4]. Anionites in different salt forms were studied using IRspectroscopy method according to [5].
Experimental method. Experiments were carried out under dynamic conditions in temperaturecontrolled columns with fixed anionite layer. Flow rate of solutions was 2 - 6 specific volumes perhour during sorption phase and 1 specific volume per hour during elution phase. The flow rate of
the solutions was controlled every hour. Rhenium sorption was carried out at room temperature andelution at 40 C. Daily filtrates were put together, mixed and analyzed for rhenium and uranium.
Before elution the anionite was washed with distilled water to pH=4. Column effluents werecollected every hour in a separate container and analyzed for rhenium.
Results and Discussion
Rhenium recovery from wash sulfuric acid of Balkhash copper smelter. It was found earlier byscientists of the Institute of Metallurgy and Ore Enrichment (Kazakh Academy of Sciences) thatrhenium during concentrate smelting in Vanukov furnaces is distributed as follows: up to 70 % goesto the gas, 10 to 15 % - to the matte, 7 to 8 % - to the dust, and 16 to 17 - to the slag [6].
Due to absence of circulation the volume of wash sulfuric acid is growing, which affects adversely
rhenium concentrations in it. Monitoring of rhenium and H2SO4 concentrations in wash sulfuric acidsolution showed that concentration of sulfuric acid in the wash solution is from 30 to 192 g/dm3(mainly 60 to 80 g/dm3) and rhenium concentration is from 11 to 34 mg/dm3 (mainly 12 to 14
mg/dm3). The total quantity of rhenium is commercially viable. In the future rhenium quantity
would be increased due to processing of rhenium-bearing ores from Aktogai and Bozshekul
deposits. Similar solutions are used in Poland at KGHM plant for rhenium recovery using sorption
technology [7].
Previously rhenium was recovered from wash sulfuric acid solutions at the Balkhash copper smelter
using anionite AN-21 in the form of gel and later in the form of porous material [8, 9].
Concentration of rhenium in the solution was from 40 to 185 mg/dm3 and sulfuric acid - from 100 to
300 g/dm3.
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In this work weakly basic anionite А170 with macro-porous structure was used. Effect of solution
flow rate (2, 4 and 6 specific volumes per hour) and salt form of the anionite (hydroxide, chloride,sulphate, hydrosulphate and nitrate) were studied. Also, parameters of rhenium elution from theionite were studied. Rhenium sorption was carried out from industrial wash sulfuric acid solution
containing 13 mg/dm3 of rhenium, 60.5 g/dm3 of sulfuric acid and sediments of the lead-containing
slime. Therefore, the acid solution was filtered. Some times red sediment appeared in the solution.
It was established using different physical and chemical methods that the sediment is selenium of
red modification.
In order to reduce duration of the experiments with different flow rates and anionite forms affecting
sorption characteristics, some rhenium was added to the wash sulfuric acid solution to get rhenium
concentration at 186 mg/dm3.
According to the experimental data (Figures 1 and 2), rhenium is sorbed from the solution quite
well. This is confirmed by the quantity of the solution passed through the anionite and by the quantityof rhenium sorbed. After 3000 volumes of the solution per volume of anionite have passed through theanionite column rhenium concentrations in the column effluents is 95 % of the original one. One
cubic centimeter of the anionite sorbs 27 mg of rhenium.
Presence of selenium in kind of a halo ring on the surface of the anionite in the column was
detected in experiments. Similar selenium behavior was found in the past during rhenium recovery
with AN-21 anionite from wash sulfuric acid solutions at the Balkhash copper smelter.

Fig. 1. Rhenium sorption curves from industrial
wash solution on А170: 1 – Re share in filtrate, 2– Re concentration in filtrate

Fig. 2. Quantity of absorbed rhenium
from wash solution per 1 cm3 of theanionite

It was established that follow rate of the solution through the column in the studied interval (2, 4
and 6 volumes per volume per hour) affects rhenium sorption: share of rhenium in the filtrate after
the column and rhenium sorbed per 1 cm3 of the swelled anionite. However, when 150 volumes
Table1. Influence of the solution flow rate to sorption characteristics of А170 anionite
Specific
volumes
100
200
300
400
500
600
700
800
900
1000

2
Breakthroughof Re infiltrate, %
2.15
3.20
6.00
15.10
21.20
26.50
37.45
52.50
77.30
87.40

Re, sorbedbyanionite,
mg/sm3
18.37
36.39
53.91
69.94
84.70
98.69
111.02120.96126.24129.03

Flow rate of solution, sp.vol./h4
Breakthrough Re, sorbed byof Re in anionite,
filtrate, %mg/sm3
2.15
18.26
3.96
36.21
6.45
53.65
20.92
68.65
24.32
82.90
27.05
96.65
67.57
103.4380.40
107.5488.95
110.0095.50
111.09

6
Breakthroughof Re infiltrate, %
2.96
5.91
8.17
34.41
51.61
59.46
70.27
80.29
90.35
97.50

Re, sorbed byanionite,
mg/sm3
18.04
35.78
53.08
66,72
76.02
83.81
89.88
94.18
96.43
97.10

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011of the solution per volume of the anionite have passed through the column with flow rate 2, 4 and
6 volumes per volume per hour rhenium share in the filtrate is ~ 3 %, and the quantity of sorbed
rhenium is 27 mg/ cm3 approximately (Table 1).
Influence of flow rate became more obviously during increasing of quantity of solution passed
through anionite. When 1000 volumes of the solution per volume of the anionite have passed
through the column sorption characteristics depend on the flow rate. At 2 specific volumes per hour
flow rate rhenium share in the filtrate is 87.4 %, and quantity of the sorbed rhenium is 129 mg/cm 3;
at 4 specific volumes per hour flow rate rhenium share in the filtrate is 95.5 % and quantity of thesorbed rhenium is 111.1 mg/cm3; at 6 specific volumes per hour flow rate rhenium share in thefiltrate is 97.5 % and quantity of the sorbed rhenium is 97.1 mg/cm3. The revealed regularity isquite explainable: first rhenium sorption takes place at the surface of anionite grains. In this casesteric hindrances for diffusion of hydrated perrhenate ions to ionogenic groups of the ionite areminimal; therefore flow rate of the solution has no effect to the sorption characteristics. In time
sorption proceed in deeper layers of the grain, where access of perrhenate ions to ionogenic groups
is hindered. This is the reason for deterioration of sorption characteristics of the anionite withincrease of the flow rate.
It was established that the salt form of the anionite does not affect its sorption characteristics (Figure 3).
According to IR-spectra samples of А170
anionite were converted into the defined forms.
This conclusion was made on the basis ofcomparative analysis of the IR-spectra, in which
typical for inorganic acid and alkali anions
absorption bands were found: HSO4‾ (1200,
1080, 1000, 880, 840, 600, 550 cm-1), SO42‾(1100, 620 cm-1), NO‾3 (1380 cm-1), OH‾ (3400
cm-1). Since anionite in chloride form has no
typical absorption bands, completeness of its
conversion into the form was determined on thebasis of equality of chloride concentrations in theFig. 3. Influence of salt form of anionite on
filtrate and the original solution.
Re sorption:1 – hydroxide, 2 – cloride,
For all anionite form studied quantity of adsorbed
3 – hydrosulfate, 4 – sulfate, 5 – nitraterhenium (full dynamic capacity) is 111 mg/cm3(Figure 3). Therefore, all studied anionite forms are suitable for rhenium recovery from sulfur acidsolutions.
The results of rhenium elution with ammonia solution from the anionite containing 27 mg ofrhenium per 1 cm3 of swelled anionite (saturated with wash sulfuric acid solution from the Balkhashcopper smelter) demonstrate high performance of this process (Figure 4). Maximum concentrationof rhenium in the column effluent was 7.7 g/dm3, and minimum concentration - 0.022 g/dm3. Morethan 96 % of rhenium is recovered from theanionite with four specific volumes of the eluent.
The average rhenium concentration in 4 combined
volumes of column effluent was 5.44 g/dm3. It is
possible to produce ammonium perrhenate fromcolumn effluents with the above said rhenium
concentrations via evaporation of the solutions
factor 10 to 12 times. This technique is used insorption technologies for rhenium recovery fromsolutions of non-ferrous metallurgy [7, 9, 10]. For
almost complete elution of rhenium it is sufficient Fig.4. Rhenium elution profile for eluant (3to use six volumes of eluent per volume of ionite.
mole/dm3 ammonia): 1 – concentration in eluate,
2 – recovery from anionite.
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Rhenium recovery from underground leach solution and effluents of uranium sorption. Sorptionextraction technology for rhenium recovery from such solutions using highly basic anionite forsorption and eluents for uranium extraction are described in [11]. More effective sorption
technology with use of weakly basic anionite AN-21was also developed. It was reasonable todetermine if widely advertised weakly basic anionites by Purolite could compete with AN-21.
Experiments were carried out with А170, А172 and AN-21 anionites for comparison. Sorption
capacity of the anionites was evaluated when breakthrough of rhenium in the column effluent is at
100 %. The following criteria for comparison were used: quantity of wash sulfuric acid passed
through, time required for full saturation of the ionite, quantity of sorbed metals per ton of dry
anionite (full dynamic capacity (FDC) of anionite). Composition of the solutions is shown in Table 2.
Four volumes are intended forevaporation to produce ammonium
perrhenate and two volumes are
Setting
intended for preparation of effluent
Filtrate, Re
for subsequent rhenium elution. The
Filtration
3
study showed that rhenium could be< 0.5 mg/dm
recovered with high performance
To waste
Sorption on A170
H2O
from industrial wash sulfuric acidsolutions of the Balkhash smelter
Washingusing А170 anionite. Process flow
NH4OH
Wash water sheet for rhenium recovery including
Desorption
To waste rhenium sorption, anionite washing,elution, evaporation of ammonia
200 mg/dm3 < Re Eluate Re > 200 mg/dm3
column effluents, crystallization of
crude ammonium perrhenate andEvaporation
production of commercial salt using
re-crystallization or electro-dialysis
Crystalization
methods are shown on Figure 5.
Crude NH4ReO4According to the table the difference
Mother liquor
between ULS and UF uranium
Recrystallzation or electrodialysis
solutions is only in uranium
concentrationandslightlyinFig. 5. Flow sheet for recovery of Re from washing solutions ofconcentrationsofnitrate-,chlorideBCM
and sulfate ions. It is seen from Table
2 that rhenium and uranium aresorbed together from the solutions
with all the anionites.
Washing solutions

In accordance with the evaluation criteria the row of anionites is AN-21, А170 > А172 for uranium
sorption from the underground leach solution and А172 > AN-21, А170 for rhenium sorption fromthe same solution. Full dynamic capacity regarding to uranium is 26.66 (AN-21), 27.5 (А170), 8.73
(А172) kg per ton, and regarding to rhenium 1.67, 1.77, 6.74 kg per ton respectively. Saturation of
the anionites with uranium is achieved 14 – 25 times faster that that for rhenium. The number of
specific volumes of the solution per volume of swelled anionite is 200 (AN-21), 230 (А170), 770(А172) for uranium and 5100, 4900, 11344 for rhenium respectively.
According to the criteria the raw of anionites is AN-21, А170 > А172 regarding to uranium
sorption from the uranium filtrates. For rhenium the raw of anionites is the same for both solutions.
Full dynamic capacity of the ionites for sorption from column effluent is smaller for uranium (5.0kg per ton (AN-21), 5.6 kg per ton (А170), 0.8 kg per ton (А172)) and bigger for rhenium (3.76;
3.95; and 13.82 kg per ton respectively) as compared to that for the underground leach solutions.
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Table 2. Recovery of Re and U from solutions of UL and UF by anionites AN-21, A170, A172

Anionites
Parameters
AN-21
A170
A172
Re
U
Re
U
Re
U
Underground leaching solutions (ULS)
3
Concentration, mg/dm : 0.48 Re, 60 U, 14000 SO42-, 210 CI-, 150 NO3-, 144 SiO2, 264 Fe3+, 1156
Fe2+, 427 Ca2+, 547 Mg2+, 964 AI3Breakthrough of metals in filtrate, %
100
95.3
98.0
99.0
100.0
97.12
Time of ionites saturation, days
42
2
41.0
2
91
4
Average flow rate of solution, sp. vol./h
5.2
5.3
5.2
Quantity of passed solutions before
5100
200
4900
230
11344
770
breakthrough of metals in filtrate, sp.vol.
Full dynamic capacity (FDC) of anionite),
1.67
26.66
1.77
27.5
6.74
8.73
kg/per ton of dry anionite
Filtrates after sorption of uranium from underground leaching solutions (UF)Concentration, mg/dm3: 0.48 Re, 1 U, 13800 SO42-, 160 CI-, 120 NO3-, 140 SiO2, 260 Fe3+, 1150
Fe2+, 425 Ca2+, 550 Mg2+, 970 AI3+
Breakthrough of metals in filtrate, %
97.0
96.0
98.5
98.3
97.9
96.0
Time of ionites saturation, days
56
42.0
57
52
165
47
Average flow rate of solution, sp. vol./h
5.0
5.1
5.3
Quantity of passed solutions before
6740
5010
7020
6300 19820
2000
breakthrough of metals in filtrate, sp.vol.
Full dynamic capacity (FDC) of anionite),
3.76
5.0
3.95
5.6
13.82
0.8
kg/per ton of dry anionite
Due to low metal concentrations in these solutions (0.48 mg/dm3 Re and 1.0 mg/dm3 U) the volumeof the solutions passed through ionites is big and the saturation time is long (Table 2).
According to the experimental data А172 anionite is better than the others for rhenium sorption
from both solutions. AN-21 and А170 anionites are almost identical on their sorption
characteristics.
Preliminary experiments on rhenium elution from А172 with aqueous ammonia showed thatrhenium cannot be recovered from the ionite. Since AN-21 and А170 are practically identical intheir sorption characteristics all further experiments were carried out with А170 anionite saturated
from both solutions.
As it is shown above, rhenium and uranium are sorbed collectively from the solutions andcan be separated at elution stage. Referring to the literature data ammonia solution was selected aseluent for rhenium and sulfuric acid solution was selected as eluent for uranium. The eluents werepassed through anionite at flow rate 1 specific volume per hour. The experiments were carried out
with the anionites saturated from ULS containing 3.02 kg/ton of rhenium and 40.0 kg/ton of
uranium and saturated from UF containing 6.44 kg/ton of Re and 2.1 kg/ton of U.
Rhenium elution was carried out at 50 °C with 3 mol/dm3 ammonia solution concentration. Elution
was stopped when rhenium concentration in the column effluent is 8 mg/dm3. No uranium was
detected in the ammonia column effluents. The results are shown on Figure 6. Second specificvolume of effluent has maximum rhenium concentrations (330 and 187 mg/dm3). In eight specificvolume of eluent the concentration goes down steeply and then gradually. First eight specificvolumes of column effluent contain ~ 50 % of the total anionite capacity and 30 specific volumes,
from 70 to 80 % of the total anionite capacity. The remaining quantity of rhenium in the anionite isconsidered a circulating load. Different concentrations of rhenium in the column effluents dependon different rhenium content in the anionites.

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Fig. 6. Rhenium elution profile by ammonia (1) and recovery of Re from anionite A170 (2), saturated byrhenium from ULS and UF. Content of rhenium, mg/g: a – 6.44, b – 3.86

After rhenium desorption the anionite containing 2.1 kg per ton of uranium was washed with water.
Uranium elution was carried out with sulfuric acid solution (100 g/dm3) and with acidic solution ofammonium nitrate (pH – 0.45) at room temperature. It is shown (Figure 7) that uranium is almost
completely eluted with 8 specific volumes of nitrate-containing effluent and 15 specific volumes ofsulfuric acid solution.
Thus, solutions containing only rhenium or uranium can be obtained using different eluents. Due tothe low concentration of rhenium in the ammonia column effluents second phase of concentration isnecessary. Liquid solvent extraction with triallylamine and tributylphosphate mixture is described in[12, 13]. We used А170 weakly basic ionite for secondary concentration. Since weakly basic
anionites do not work in alkaline media
rhenium-bearing column effluents were
neutralized with inorganic acids to weakly
acidic state and ammonium was distilled off.
Referring to the fact that nitric and hydrochloric
acids are strong depressants for perrhenate ions,sulfuric acid was used for neutralization.

Fig. 7. Uranium elution profile by nitrate (1) andsulfate (2) solutions and recovery of U from anionite(3, 4) correspondingly

The ammonia column effluents contained 54
mg/dm3 of rhenium, 2370 mg/dm3 of nitrates,
170 mg/dm3 of sulfates, and 1 mol/dm3 ofammonia.

The flow rate was 4 specific volumes of solution per hour. Sorption was carried out at room
temperature.
Every 50 specific volumes column effluents were assayed for rhenium. Saturated anionites were
washed with water, collected together and rhenium was recovered from it in dynamic conditions
with 3 mol/dm3 ammonia solutions at 50 °C and one specific volume per hour flow rate.
The results of rhenium sorption from two types of neutralized ammonium column effluentsand Re desorption from the anionite are shown on Figures 8 (sorption) and 9 (elution).

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Fig. 8. Rhenium elution profile from evaporated(1) and neutralized (2) eluates

Fig. 9. Rhenium elution profile (1) and its
recovery from anionite (2)It is seen from Figure 8 that pretreatment of the solution does not affect sorption characteristics.
One ton of dry anionite absorb 83 kg of rhenium from the evaporated solutions and 78 kg ofrhenium from the neutralized solutions at 2200 and 1800 specific volumes of the solution
respectively.
Rhenium is eluted well with ammonia (Figure 9). Five specific volumes of ammonia recover 95 %of rhenium with maximum concentration of 22.3 g/dm 3. The average rhenium concentration in
combinedcolumnUranium sorption
Ammonia
effluents was 4 g/dm3.
Water
filtratCrude
ammoniumAmmonia
Sorption of Re, washing of saturated Poor eluate
perrhenatecanbeobtaineds desorption of rhenium
anionite,from such solution using
Preparation of eluent
evaporation and cooling
Filtrate Wash waterRich eluate
H2SO4
operations similar to theoperations
usedin
Ore leaching
Evaporation or neutralization
nonferrous metallurgy for
Ammoniarhenium recovery.
Water
Solution
A process flow sheet for
NH4OH production fromSorptionofRe,
washingofsaturated
Filtrate > 1 mg/L Re
anionite, desorption of rhenium
uranium sorption filtrates
olution(Figure 10) is proposed
Filtrate < 1 mg/L Re Wash water Rich eluate
Poor eluate
on the basis of the study.
The flow sheet is more
Evaporation
environmentally safe (dueto elimination of toxic
Crystallization
triallylamine and tributyl
phosphate,
flammable
Mother liquor
Crude NH4ReO4
keroseneandhigheralcohol), more efficient (2Recrystallization or electrodialysis
rhenium
concentration
operations instead of 3),
Fig. 10. Flow sheet for recovery of rhenium recovery from uranium sorption
ionite capacity regarding
filtrates
to rhenium is higher asrecompared to other options, it uses less aggressive eluent and cheaper.
Conclusionse

On the basis of the results of the study on rhenium sorption from industrial wash sulfuric acidsolutions from the copper smelter with low Re concentrations and from Kazakhstan uranium ore
underground leach solutions withrodia
ultra-low Re concentrations using А170 and А172 weakly basic
y
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anionites and rhenium desorption from А170 ionite depending on the criteria of the processes theflow diagrams were developed.
References

1.
Z. S. Abisheva, A. N. Zagorodnyaya, N. S. Bekturganov. Review of technologies for rhenium
recovery from mineral raw materials in Kazakhstan// Hydrometallurgy, 2011, vol. 109 N 1-2, Р. 1 - 8.
2. Ionites. Methods of test preparation. GOST 10897-64.
3. L. V. Borisova, A. V. Yermakov Analytical chemistry of rhenium. Moscow (1974), p. 319
4. Method for determination of uranium mass concentration. TU 640-38229886-ЗАО-02-2000.
5. K. Nakomoto, Infrared and Raman Spectra of Inorganic and Coordination Compounds,
Moscow (1991), p. 536
6. K. N. Scherban, V. V. Bobrova. In: Chemistry, technology and analytical control for rhenium.
Moscow (1990). p. 230 - 232.
7. A. Chmlearz Benke, G. Leszczynska-Segda, A. Anyszkiewicz, K. Litwinionek. Copper 2010.
Hamburg (2010). V. 5. p. 1803 – 1814.
8. A. A. Egizarov, L.I. Mekler. In: Extraction and sorption in metallurgy of molybdenum,
tungsten and rhenium. Moscow (1971). p. 17 - 24.
9. K.B. Lebedev, L. I. Mekler, E. I. Kryukova. Non-ferrous metals. Issue 2, p. 79 – 83 (1976).
10. Ionites in non-ferrous metallurgy / edited by K.B. Lebedev. Moscow (1975). 352 p.
11. A. N. Zagorodnyaya, Z.S. Abisheva, E.I. Ponomaryova, V. V. Bobrova. Non-ferrous metals.
Issue 8, p. 59 – 62 (2010).
12. I. S. Ortikov, V.P. Nebera. Non-ferrous metals. Issue 3, p. 72 – 75 (2010).
13. V. P. Volkov, N. V. Nikitin, M. A. Kikhailenko et al. In: Proceedings of the 5th International
Basic and Applied Scientific Conference. Actual issues of uranium industry. Almaty. 2008, p. 353.

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3.3.
DEVELOPMENT OF THE TECHNOLOGY FOR PRODUCTION OF HIGHPURITY AMMONIUM PERRHENATE AT BALKHASH COPPER
SMELTER, REPUBLIC OF KAZAKHSTAN
E.А. Ospanov, E.I. Gedgagov*, N.A. Ospanov, S.V. Zakharyan
BALKHASH COPPER SMELTER, REPUBLIC OF KAZAKHSTANFSUE “GINTSVETMET Institute”,
13, Acad. Korolyov Street, 129515, Moscow, Russia, e-mail: gin@gintsvet.msk.ru

The Republic of Kazakhstan is within five world’s largest rhenium producers. The main source ofrhenium in Kazakhstan is copper ore and Kazakhmys is virtually copper monopolist in Kazakhstan
The copper concentrate is processed in electric furnace (Zhezkazgan smelter) and Vanyukov
furnace (fluidized bed furnace, Balkhash smelter). During smelting and converting processes therhenium sublimates with the gas which goes through dry ESP, cooling and washing processes andfinally fed to the Acid plant to produce strong sulfuric acid. At this stage up to 70% of initialrhenium in the feed is reported to the washing sulphuric acid (weak acid).
The weak acid produced at Zhezkazgan copper smelter is supplied as a rhenium-containing feed toZhezkazganredmet (Zhezkazgan rare metals plant) being 50% owned by Kazakhmys and 50% by
the Government. The technology used at the plant is solvent extraction (SX) with followed bytrialkylamine re-extraction with ammonia solution and crystallization.
The weak acid produced at the Balkhash commissioned in 2007 acid plant is the primary potential
source of rhenium. It is the low rhenium grade at comparatively large flow determined the selectionof the extraction method – sorption in resin-based water-insoluble ion-exchangers. The weak acidproduced at Balkhash acid plant is featured by presence of selenium.
The purpose of this article is to give idea about the technology used for processing the sulfuric acidsolutions produced at Balkhash acid plant, based on industry tested sorption processes featuringhigh rhenium and selenium recoveries and producing high-grade ammonium perrhenate andmetallic selenium.
The total process flowsheet includes two stand-alone sorption sections. The first one provides forcomplete rhenium extraction. The rhenium-free solution containing the remaining selenium
produced by the main rhenium sorption is fed to the same stand-alone selenium sorption process as
well. The second stage sorption producing elemental selenium.
A special attention in the development of the sorption-based technologies should be paid topreventing the impurities from poisoning the ion exchanger as well as to development of the ion
exchanger regeneration technologies.
Thus, implementation of the developed Balkhash acid plant solutions processing flowsheet willallow significant increase in high-quality APR-0 grade ammonium perrhenate production.

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3.4.
USE OF ION-EXCHANGE RESINS FOR PRODUCING HIGH-PURITYAMMONIUM PERRHENATE IN PROCESSING OF CRUDE ORE AND
MANMADE RHENIUM-CONTAINING RAW MATERIALS
E. I. Gedgagov* and N. E. Nekhoroshev***GINTSVETMET Institute, ul. Akademika Koroleva 13, Moscow, Russia
e-mail: gin@gintsvet.msk.ru**ZAO VR, ul. Radio 7, Moscow, Russia
e-mail: nk@pzcm.com

Keywords: perrhenate, crude ore, rhenium wastes, rhenium sorbents

Introduction
The Flowsheets used for processing crude ore and manmade rhenium-containing raw
materials differ from those for processing the other metals by a wide variety of processes intended
for manufacturing commercial ammonium perrhenate for the following reasons. On the one hand,rhenium recovery is relatively easy because perrhenate anion is the major rhenium species inaqueous solutions almost over the entire range of hydrogen ion concentrations; and on the other,
this low-hydrated anion has no rivals in absorption, except for anions of the strongest acids known
hitherto. One more reason for diversified technologies is small production volumes, and a pilotscale sorbent batch of no more than several hundred liters in volume is sufficient for filling sorption
apparatuses. Another aspect of the problem is the selection of a sorbent to desorb the absorbed
perrhenate anion to a vanishingly low residual capacity easily and with a small volume ofammoniac solution. Such properties are intrinsic to low-basicity anion exchangers or amphotericsorbents, and to reach all required properties of sorbents is not an easy task. Before assessing therecent advances in synthesis of sorbents, it is expedient to carry out a retrospective review ofsorption recovery methods.
Retrospective review
The first industrial low-acidity styrene-divinylbenzene anion exchangers, for example, AN-21,
were unable to recover rhenium at high acidities, and it was recommended to dilute these acidsolutions with water. However, this was not the only drawback of the then-existing low-basicity
anion exchangers. Passage of considerable amounts of an ammoniac desorbent was required forrhenium to be desorbed from anion exchanger AN-21, so that eluates were diluted many times over.
The idea of crosslinking resins (that is, providing a polystyrene matrix with high divinylbenzene
percentage in the form of crosslinked chains) with the goal of causing a sieve effect at the ionexchange phase boundary, was first embodied in anion exchanger AN-21x14 (by K.B. Lebedev);
this anion exchanger was intended to be used in purifying rhenium from molybdenum inmolybdenum-rhenium concentrate processing flowsheets [1]. Upon sorption from scrubber
solutions, perrhenate anion easily penetrates the depth of ion-exchanger grains, while bulky
molybdenum polyanions remain in solution for the reason that the resin matrix has a rigid structure.
The Pobedit plant also employed resin AN-82x14 for recovering rhenium from molybdate
solutions; this resin was synthesized using the known idea of crosslinking to create a rigid ionexchanger framework [3]. At the All-Russia Research Institute of Chemical Technology (by N.G.
Zhukova and A.I. Zorina), a 2-methyl-5-vinylpyridine matrix was used to create a rhenium resin;
but unlike AN-21, this new resin belonged to the class of ampholytes, and this was only in order to
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improve the conditions for rhenium desorption by weak ammoniac solutions [9]. In this way, theplant in Dneprodzerzhinsk produced a pilot lot of VP-14KR (a known ampholyte) [3], and it waslater modified to VP-18KR. The major drawback of those resins consisted of acidity limitations;that is, they were low efficient at acidities above 100 g/l of sulfuric acid, but the ammoniac
desorption of rhenium was over after the passage of no more than two or three specific volumes ofthe desorbent. Despite a limited range of available resins, the practice of using ion exchangers inrhenium sorption finally culminated in commercialization at the Pobedit Plant [2], at the Chimkent
Lead Plant (in sorption from zinc–cadmium sulfate solutions) [4], at the Skopino Mining andMetallurgical Plant (in sorption from post-molybdenum-sorption solutions), at the Severonikel
Plant, at the Uzbekistan Plant of Refractory and Heat-Resistant Metals [3], and at the Kirgiz Ore
Mining Plant [5]. A characteristic example of employing a sorption method in the absence of alarge-scale production of special sorbents was the commercialization [7] of technology forreprocessing aluminum–platinum–rhenium spent catalysts at the Severonikel Plant (by N.E.
Nekhoroshev). Ampholyte VP-1K was employed for recovering rhenium; this ampholyte had been
designed for recovering tungsten polyanions, but was used for rhenium not only because of the low
basicity of its functional groups but also following the then-known principle of "being available off
the shelf." Despite this principle, the tungsten ampholyte demonstrated acceptable rhenium sorption
values, and this was not barred by the propensity of the ampholyte to swelling with a coefficient
exceeding 5.5 ml/g resin and the associated considerable dilution of rhenium-containing eluates.
Certainly, more recent studies carried out by scientists from the St.-Petersburg Technological
Institute (A.A. Blokhin) in collaboration with specialists from the Purolite company (M.A.
Mikhailenko) provided an optimal version of sorbent synthesis for recovering rhenium fromsolutions after leaching rhenium-containing catalysts, namely, anion exchanger Purolite A170 [8].
The range of resins for rhenium is not confined to low-basicity ion exchangers that have beenused in acid media. Neutral and alkaline solutions, for example, carbonate–bicarbonate systems ofunderground uranium leaching, can be reprocessed to recover rhenium only with the use of strongly
basic anion exchangers. These anion exchangers have high rhenium sorption capacities compared to
the low-basicity ion exchangers over a wide range of hydrogen ion concentrations, but inasmuch as
rhenium desorption from them was extremely difficult, the vector of research was redirected to theselection of reagents providing the most efficient sorption, frequently without worrying about
detrimental phenomena, such as chemical destruction and poisoning of ion exchangers. At different
times, proposed were solutions of ammonium thiocyanate, nitric acid, hydrochloric acid, andvarious combinations thereof, with or without heating, in a dynamic mode or under stirring in abatch mode. Moreover, a variant of extractive desorption has been proposed for separating rhenium
and molybdenum (at GINTSVETMET). According to this technology, a strongly basic resin
saturated with rhenium and molybdenum is contacted with a tertiary amine extractant. As a result,
the rhenium is quantitatively transferred to the extractant phase (from which it can easily bedesorbed by a weak ammoniac solution) whereas molybdenum, which is sorbed in the form of largepolyanions, practically all remains in the resin and can also be desorbed by ammonia--salt mixtures,
but without rhenium. The rhenium/molybdenum separation factors are very high, which helps
reduce hardware design and one-time downloads of resins used for the separation.
Processes with rhenium microconcentrations have become a very important line in rhenium
recovery technologies. In particular, this will help come close to solving the long-standing problem
of recovering rhenium from an unusual system such as fumarolic gases from the Kudryavy Volcano
on the island of Etorofu of the Kuril Chain, where the yearly rhenium amount is estimated at several
tons. Presumably, upon water entrainment of rhenium heptoxide from fumarolic systems, solutions
can form where rhenium concentrations will be such that to require the use of flowsheets withrhenium microconcentrations. Very important studies intended to find sorbents suitable for
operating with rhenium microconcentrations (these sorbents are necessary for finding otheralternative sources of rhenium) are now underway at the Russian University of Chemical
Technology (by I.D. Troshkina), at the St.-Petersburg State Technological Institute (A.A. Blokhin),
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011at GINTSVETMET (by E.I. Gedgagov), and at other scientific centers. Underground uranium
leaching solutions are a real source of rhenium. In this context, there are increasing suggestions tocarry out the associated recovery of rhenium by sorption from underground uranium leachingsolutions, where rhenium contents are less than 0.5 mg/l. Uranium–rhenium solutions are not a new
system. As early as in 1986, a sorption–extraction combination technology for undergroundleaching solutions of uranium ores was commercialized at the Fifth Mining Group of the Leninabad
Mining and Chemical Plant (by A.N. Zagorodnyaya). Strongly basic anion exchanger AM, which
was proposed for recovering rhenium from solutions containing rhenium in amounts of 0.25 mg/l
on average, provided a high degree of rhenium recovery (70%) along with extractive
preconcentration from eluates. Attempts have also been made (at GINTSVETMET) to recoverrhenium by sorption from the clarified portion of the sludge field of the Uzbekistan Plant ofRefractory and Heat-Resistant Metals, tailings of the Erdenet plant (in Mongolia), and settling
sumps of the beneficiation cycle at the beneficiation plant of the Dzhezkazgan Mining andMetallurgical Plant [6]. In all of these cases, evidently, processes for recovering rhenium fromsolutions with 0.1--0.2 mg/l have quite a different hardware design. Apparatus with a stationary
resin bed should have been substituted by pressurized columns with the highest linear rates hitherto
unknown in nonferrous metallurgy, and if it were so, rhenium recovery technology could havebecome a replica of underground leaching technology for uranium. And given the persistently rising
prices and shortage of supply, we cannot rule out that this scenario is quite realistic for rhenium.
Recent advances in synthesis of sorbents
The current situation in the synthesis of resins in Russia is such that, for rhenium, in the near
future here will be need to purchase ion exchangers produced by the leading companies abroad, andthis work has been already started. Studies on the synthesis of sorbents, specifically, for rhenium,
are now underway in other companies, too, for example, Lanxess (Germany), Rohm & Haas, and
Dow Ch. (both in the USA), and others.
The Russian Federation does not have significant sources of rhenium-containing ore material;
however, there are some measures that can help achieve a substantial progress in the provision of
Russia with rhenium (which is certainly the metal of future progress in aerospace science), namely:
careful attention to technologies for reprocessing all possible waste (superalloy, spent catalyst,
binary alloy, and other waste), solving the problem of reprocessing systems with rhenium
microconcentrations (volcanic eruptions, underground leaching of uranium solutions, and so on), as
well as attention from the government to the creation of the domestic industry for the synthesis ofsorbents and multilateral scientific and practical discussion of the achievements at various
conferences.
References.
[1]. Lebedev, K.B., et al., Ion Exchangers in Nonferrous Metallurgy, Moscow: Metallurgiya, 1975.
[2]. Korneeva, S.G., "Recovery of Rhenium in Processing of Molybdenite Concentrates at thePobedit Plant," in Collected Works of GINTSVETMET, 1990, pp. 85--87.
[3]. Rumyantsev, V.K., Vol'dman, S.G., and Kulakova, V.V., "Associated Rhenium Recovery inProcessing of Molybdenite Concentrates," Tsvet. Metally, No. 7, 1991, pp. 33--39.
[4]. Abisheva, Z.S., Zagorodnyaya, A.N., and Ponomareva, E.I., "The State and Prospect of RareMetal Industry in Kazakhstan," News of Science of Kazakhstan, 2000, No. 2, pp. 7--10.
[5]. Gedgagov, E.I., and Besser, A.D., "The Russian Federation as Part of the World's Market for
Refractory Metals Raw Materials," Khim. Tekhnol., 2000, No. 1, pp. 15--24.

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011[6]. Volk, V.I., Vakhrushin, A.Yu., and Besser, A.D., "Technology for Recovering Rhenium from
Solutions with Extremely Low Rhenium Concentrations," Tsvet. Met., 1999, Vol. 35, No. 6, pp.
16--19.
[7]. Gedgagov, E.I., "Development of Scientific Rationale and Commercialization of Molybdenum,
Tungsten, and Rhenium Sorption on High-Porosity Ion Exchangers," Abstract of Doctoral
Dissertation., 1989, 380 pp.
[8]. Blokhin, A.A., Mal'tsev, E.E., et al., "Ion-Exchange Recovery of Rhenium from MolybdenumContaining Sulfuric Acid Solutions," Tsvet. Met., No. 2, 2005, pp. 59--62[9]. Baskakov, A.N., et al., "Copolymers of Vinylpyridine, Divinylbenzene, and Vinylphenylacetic
Acid and Methods for Their Preparation," USSR Author's Certificate No. 969006, June 22,
1982.

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3.5.

PUROLITE® ION EXCHANGE RESINS FOR RECOVERY AND
PURIFICATION OF RHENIUM
Mikhaylenko, M.
Purolite International Limited, Representation office in the CIS, Lusinovskaya 36, Moscow, 115093, Russia,
purolite_mm@co.ru

Rhenium supply in the world market is fed from two main sources: processing ofdifferent ores and recycling of secondary materials.
Hydrometallurgical methods are used for processing the rhenium feed. Often the SX,
precipitation and membrane separation techniques are used to recover and purify rhenium
from other elements. However in many practical cases application of rhenium selective
resins provide the most direct and simplest, and consequently the most economical way to
produce ammonium perrhenate of high grade.
Purolite® manufactures two rhenium selective resins: Purolite® A170 and A172. Bothresins are weak base anion exchange resins made of polystyrene-divinylbenzene polymer,
but the first one is macroporous and the second is gel type. Effective desorption of rhenium
can be done by either sodium or ammonium hydroxide. Enrichment coefficient in desorbate
can be as high as 103 order of magnitude.
The A170 resin is perfect for recovery of rhenium from solutions comprising of 1 toseveral hundred ppm of rhenium, up to several hundred grams per liter of sulfuric acid, highchloride. The rhenium recovery is very selective in regards of common alkali, alkali earthand base non-ferrous metals. Such solutions are commonly generated by copper smelters
and two large smelters have already installed this resin.
The A172 resin is tailored for selective separation of rhenium from molybdenum. This
technical task is quite difficult due to very similar chemical properties of perrhenate andmolybdate compounds in aqueous solutions. Such solutions are obtained at processing ofmolybdenite concentrates.
Other application of the A170 resin is rhenium recovery from low grade solutions. An
example is sulfuric uranium PLS where rhenium concentration is typically 0.5 to 3 ppm.
This resin has been installed at Navoi GMK, Uzbekistan to recover rhenium from uranium
barren solutions, i.e. after sorption of uranium by strong base anion exchange resin, and has
been successfully operating for several years.
Finally, the A170 resin can be effective for recovery of technetium from acidic
solutions.

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3.6.
PHYTOMINING OF RHENIUM - AN ALTERNATIVE METHOD FORRHENIUM PRODUCTION
Ognyan Bozhkov1, Christina Tzvetkova1, and Ludmila Borisova2
1

Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences,
Acad. G. Bontchev str., bl. 11, Sofia, 1113 Bulgaria,
e-mail: bozhkov@svr.igic.bas.bg
2
Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygina str. 19,
Moscow, 119071 Russia

Keywords: rhenium, phytomining, plant hyperaccumulators, ammonium perrhenate
Abstract:

Phytomining is the uptake and preconcentration of bioavailable metal species from the environment
into the plant biomass in a natural way. Rhenium possesses the unique property to accumulate andconcentrate as perrhenate in the green parts of all terrestrial and aquatic plants in amounts manytimes exceeding its natural occurrence, which is a precondition for its phytomining. Our approachfor Re phytomining from soils and waters was as follows: a) carrying out regional investigations on
Re distribution in the vegetation around the copper mine „Asarel”- Bulgaria and locating areas withindustrial importance of Re concentration in the vegetation; b) discovering plant species, which arerhenium hyperaccumulators; c) developing a procedure for efficient Re extraction from the plantmass and obtaining pure NH4ReO4. As a result of the application of our approach: a) we found thepoints in the area around the copper mine „Asarel”- Bulgaria which are of industrial importance as
regards the Re concentration in the vegetation; b) we discovered four plant species as new
hyperaccumulators of Re suitable for its phytomining; c) we developed two procedures forquantitative extraction of Re from the plant mass and a simple procedure for purification of theleachate from the main ash elements such as K, Ca Mg and Cu. The final solution contains 98.2 %of Re and only 1.8 % of impurities as a sum of the main ash elements.
Introduction
The phytoextraction of metals or mining with plants (phytomining) is the uptake andpreconcentration of water-soluble metal compounds (bioavailable species) from the environment
into the plant biomass. The plants absorb metals through the root system and store them in the root
biomass and/or transport them up into the stems and/or leaves [1, 2]. A living plant may continue toabsorb substances until harvested. The main advantage of phytoextraction is its environmental
friendliness. Another benefit of phytoextraction is that it is less expensive than any other method forrecovery of metals from polluted soils without damage of the environment [1, 2]. Enough is thecontaminated area to be plants with the crop and after plant development to harvest the green mass. The
further step is to extract the metal from the plant mass, usually by incineration of the latter.
In our previous studies it was found that the plant biosphere is a natural extractor and concentratorof rhenium from soils and waters [3]. A basic feature of Re is that this metal is preferably
accumulated (more than 98%) in the green over ground parts of all kinds of plants. It wasestablished that the plant biosphere in the vicinity of copper mines and copper processing factories
was enriched with rhenium in amounts exceeding its natural abundance in Earth’s crust by a factorof 214 to 1.98x106 [3,4]. Therefore, phytomining is appropriate to be applied in those areas, whereconventional methods for extracting the metals are not cost-effective. We also proved that thedifferent plant species have different capacity for rhenium accumulation and that the bioavailable
species of rhenium in the surface environment is the ReO4- ion [3, 4 and 5].
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Our approach for Re phytorecovery from soils and waters [4] was as follow: a) carrying out
regional investigations on Re distribution in the vegetation of the copper mine „Asarel”- Bulgaria;b) locating the areas with industrial importance of Re concentration in the vegetation; c) discovering
plant species, which are rhenium hyperaccumulators (able to accumulate 1000 g Re/t dry mass ormore; d) developing a procedure for efficient Re extraction from the plant mass and obtaining pure
NH4ReO4.
In this work we summarize the results of the application of our approach for Re phytorecovery
from soils and waters of copper mining areas with alfalfa.
Experimental
The Re content in all plant samples was analyzed by incineration of the dry plant mass, followed by Re
extraction from theashwith alkaline solution and its determination according to thespectrophotometric catalytic method for determination of ng amounts of Re with N,Ndimethyldithiooxamide (DMDTO), developed by us [6]. For field determination of the Re content in thevegetation we used the DMDTO spot test after Re extraction from the plant mass with ethanol [6, 7].
The spectrophotometric determination of Re was carried out on the double beam UV-VIS
spectrophotometer Evolution 160, Thermo Scientific. Flame AAS determinations were carried out
on the Thermo SOLAAR M5 Dual AA Spectrometer, Thermo Scientific. The samples (copper
concentrates, a soil sample and a solid sample from the tailings) were analyzed by melting with anoxidation mixture of Na2O2 and Na2CO3 at 520oC and treating the melt with water for leaching ofRe [8]. In the obtained alkaline leachates the Re content was determined according to the highly
selective and sensitive catalytic method using DMDTO [6].
Results and discussion
Regional investigation on Re distribution in the vegetation in the area around the open-air coppermine „Asarel”
Our preliminary autumn investigations in October 2006 on the degree of rhenium accumulation in
the vegetation of soils from the „Asarel” mine were insufficient to throw light on the real Re
distribution in plants from this region [3]. Nevertheless, the experiments showed that Re was not
uniformly distributed in the vicinity of the „Asarel” mine and helped us to mark several sampling
points for the subsequent regional summer investigations, e.g., close to the open mine, at the spoils,
at the installation for copper concentrate production, at the shore of the lake collecting the waste
mining waters, etc. The autumn investigations showed that acacia and birch were good collectors ofrhenium. To find the best plant biocollector of Re it was necessary to expand the plant species
sampling. The summer sampling was carried out in the second half of June 2007 [4]. We analyzed
the Re content of 22 samples, collected from 5 main points in the vicinity of the „Asarel” mine:
15 plant samples from 10 different plant species, 3 water samples, 2 samples of copper concentrates
produced in the enrichment installations of the „Asarel” mine, 1 soil sample and 1 solid sample
from the tailings [4]. The Re content in the vegetation was analyzed according to the procedures
described above [7]. The sampling points of our summer regional investigation are marked on Fig.
1 and the results of the analysis are shown in Table 1.
The summer regional investigation on rhenium distribution in the vegetation [4] showed that thecontent of rhenium in plants growing on the territory of restored spoils was lower than that in thevegetation growing near the open-air mine „Asarel” (compare the results in Table 1, points S1 andS5). These results could be explained by the lowest concentration of rhenium in soils of the spoils
because of their restoration. Analysis of the vegetation growing on the shore of the Gelev Chuchur
Lake confirmed our previous findings [4] that waterside plants can extract and concentrate rhenium
from waters [3]. On the other hand, it is apparent that different plants have a different capacity for
Re bioaccumulation (the sampling distance between the different plant species from the shore was
maximum 15 m). It could be presumed that plant species with a well developed root system would
suck more water from the lake and hence, accumulate more rhenium (see the results in Table 1, S2,
leaves of oak and bush).
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Table1. Highest rhenium concentrations found invegetation in vicinity of mine „Asarel”

S5 „Asarel” mine
S1 Restored Spoil
S2 Side of the lake
Gelev Chuchur
Chuchur
S4 Depot of Cu
concentrates
S3 r. Maresh

Panagyurishte town

Fig.1.Map of the surroundings of „Asarel”
coppers mine.

Sampling site, Sample
type

CRe g/g
ash

S1, leaves of flowering
clover
S1, leaves of acacia
S2, leaves of oak
S2, leaves of bushS2, drainage waterfrom lake
S3. river water
S3. elder leaves
S4, flotation copper
concentrate
S4, cementation copper
concentrate
S4, leaves of acacia,
5 m from depot
S4, soil – 5 m fromdepot
S4, waste water withbacteria, pH=1.5
S5, leaves of acacia
S6, tailing sample

2.30

Ratio
CRe/Clark
*
3 286

0.59
7.20
2.44
0.12 g/ml

843
10 286
3 491
171

0.04 g/ml
30.8
1.0

57.1
44000
1 429

135

192 8571686

2.41x106

5.0

7143

0.06

86

13.2
0.05

18 857
71*The Clark of Re in the Earth’s crust is 0.7 ng Re/g
The rhenium concentration in the lake water was about three times higher than that in the Riverflowing from the lake (see S2 and S3 water samples) because of the high water of river Maresh near
the town of Panagyurishte. The results of the sampling points in the area of the installation forcopper concentrate production and the depot of copper concentrate (see S4 in Table 1) are very
interesting. The concentrate which contains more than 50 g Re per ton is of industrial importance.
The average Re content in the copper concentrates varies between 1 and 3 g Re/t [9]. „Asarel” mine
produces two kinds of copper concentrates: flotation and cementation concentrates. The flotation
concentrate contains the expected amount of rhenium (1 g Re/t) while the cementation concentratecontains an extremely high amount of rhenium (135 g Re/t) [4]. It is known that the molybdenum
concentrate has the highest rhenium content [9]. What is more interesting, is that the vegetation(acacia) growing close to the depot of cementation copper concentrate is able to bioaccumulate inits leaves up to 1686 g Re/t ash in a natural way [4]. This value is of industrial importance and iscommensurable with the richest in Re molybdenum concentrates (USA, state Nevada -1030 g Re/t,South-West Africa – 2300 g Re/t, ex USSR territory-1930 g Re/t and Stavanger, Norway-3100 g
Re/t [9].
It is very probable that part of rhenium in the cementation concentrate is in the form of the easily
assimilated by plants ReO4- species. Since oxide copper concentrate is produced by bioleaching ofCu from poor copper ores with the aerobic bacteria Acidithiobacillus ferrooxidans in H2SO4
solution in presence of Fe3+ ions, it is very likely that during this process part of ReS2 is alsooxidized to ReO4-. The role of the bacteria consists of oxidation of Fe2+ to Fe3+, as well as sulphur tosoluble sulphate [10].
As the cementation copper concentrate is stored under atmospheric conditions, it is probable thatthe rainfalls wash out part of the perrhenate ions from the concentrate and thus rhenium penetrates
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the soil and is then extracted by plants. The results also evidence that the Re concentration in leavesof acacia growing 5 m away from the store concentrate is 12.5 times higher than that in theconcentrate [4]. As a result of the regional investigation [3, 4] we found the points of industrial
importance of rhenium content in the vegetation – the one close to the installation for producing
cementation copper concentrate and the other - to the depot of copper concentrate (Table 1., S4).
The regional investigation showed again that the acacia leaves are the best plant biocollector of
rhenium. However, to develop a procedure for real Re phytorecovery from soils we need a plantbiocollector which should:
 be unpretentious for cultivation and grow fast with a well developed root system; have a great quantity of green mass which is a precondition for hyperaccumulation ofrhenium; be easy for harvesting and grow again after cutting.
Taking into account these considerations, we chose alfalfa (Medicago), white clover (Trifolium
Repens), mountain-spinach (Atriplex hortensis) and buck-wheat (Polygonum Fagopyrum) for ourfurther experiments [12, 13].
Study of the capacity of the abovementioned four plant species for Re phytoextraction fromsoils spiked with ReO4- at laboratory conditions
The experiments were carried out as follows [13]. In four portions of 2.5 kg dry soil (in pots), we
put seeds of alfalfa, white clover, mountain spinach, buck-wheat and regularly watered them. After
two weeks, the seeding plants grew and developed leaves. Then each soil was spiked with 0.3218 g
Re as KReO4 solution. The concentration of Re in the soil was 128.72 µg/g soil. The plants wereregularly watered. Monitoring of the bioaccumulated Re in the samples of vegetation was carriedout in different periods after the spiking of soil. The plant samples were dried to constant weightunder atmospheric conditions. An exactly weighed quantity of dry plant mass was incinerated at
480oC and the rhenium content was determined according to the procedures described above [6, 7].
The results of the analysis showed that alfalfa is a new efficient plant hyperaccumulator of Re fromsoils [11]. It was established that after 7 days the content of Re in alfalfa growing on soil spiked
with ReO4- (CRe= 128.72 µg Re/g soil) increased up to 46 586 µg Re/g dry mass (4.66% Re) alfalfa,
respectively 294 289 µg Re/g ash (29.43% Re) and did not further increase with time. The
enrichment factor was 362 for dry mass, respectively 2286 for ash. In this way, for the first time we
prepared rhenium phytoconcentrate at laboratory conditions. The investigations showed that also
white clover (Trifolium Repens) is hyperaccumulator of rhenium from soils spiked with perrhenate[12, 13]. It was established that 22 days after spiking the soil with ReO4- (CRe= 128.72 µg Re/g soil)
the content of Re in the clover growing on this soil increased up to 35 090 µg Re/g dry clover(3.51% Re), resp. 226 553 µg Re/g ash (22.66% Re). The enrichment factor was higher than 272 fordry mass, respectively 1760 for ash. The other two plant species - mountain-spinach (Atriplex
hortensis) and buck-wheat (Polygonum Fagopyrum) accumulated up to 3150 µg Re/g dry mass or
9130 µg Re/g dry mass, respectively, which is a low capacity for rhenium bioaccumulation. Hence,these species are not perspective for practical rhenium phytoextraction from soils [13]. The
significance of rhenium hyperaccumulation by alfalfa and white clover is evidenced by the Re
content in them - 4.66% of Re in the dry mass of alfalfa, respectively 29.43% of Re in the ash and3.51% of Re in the dry mass of white clover, respectively 22.66% of Re in the ash. For comparison,
the Re concentration in the richest molybdenum concentrates is maximum 0.1-0.2 % of Re [9].
Another significant difference between these two Re containing materials is that thephytoconcentrates are obtain in a natural way (only through watering of the plants and using their
metabolism) with minimum resources, while the ore concentrates, are obtain by sophisticated highcost technologies.
As a result of our experiments we found four plant species, which are new Re hyperaccumulators.
For all further experiments, we chose the alfalfa with known Re content obtained at laboratory
conditions [13].
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Purification of the Re containing leachate from the main ash elements
In our previous study [14] we developed two procedures for 100% rhenium extraction from thegreen mass as follows: Direct incineration of the plant mass at 480oC in oxidation atmosphere, followed by alkaline
extraction of rhenium from the ash;
 Ethanol extraction of rhenium from the green mass, evaporation (or distillation) of theethanol followed by incineration of the dry organic residue at 480oC and extraction ofrhenium from the remaining ash by an alkaline solution.
The concentration of Re in the leachate was determined according to the catalytic DMDTO method[6]. The concentrations of K, Ca, Mg, and Cu in the leachate were determined by FAAS. The
experiments showed [14] that the alkaline leachate obtained after direct incineration of alfalfa
contains 52.79% of Re and 47.21% of K, Ca, Mg, and Cu (sum of the main ash elements). The
leachate obtained after ethanol extraction of Re from alfalfa contained 67.4% of Re and 32.6% of
the above mentioned main ash elements [14]. It is evident that the leachates obtained according tothese two procedures are not sufficiently purified from the main ash elements and are not suitablefor obtaining pure ammonium perrhenate. In our previous studies, we found that the rhenium
species in the alkaline leachate was ReO4- [5, 7]. On the other hand, the main ash elements - K, Ca,
Mg and Cu, are cations. The usual way for removing cations from solutions is via cation exchange
resins [15]. We chose the strongly acidic cation exchange resin Dowex 50W×8 in H+ form with a
total capacity of 5.2 ± 0.3 meq per dry gram [11]. In our experiments, we used the batch method ofsorption because of its simplicity of performance. To find the optimal time for sorption of thecations on the Dowex 50W×8 resin we carried out preliminary experiments with rhenium
containing alfalfa obtained at laboratory conditions. The investigation showed [11] that after 1 hourof dynamic contact between the liquid phase and the resin, the degree of sorption of the cations was
about 89%, after 2 hours the degree increased up to 95% and after 3 hours, it reached 99%. In all
further experiments with alfalfa for purification of leachates, the batch method was performed for 3
hours. The experiments were carried out as follows [11]:Two portions of raw alfalfa (1 g each) were treated by the two methods developed by us for
extraction of rhenium from the plant mass: by direct incineration of raw alfalfa and by ethanol
extraction of rhenium from the green mass [14]. Both 20-ml ammonia leachates were analysed for
the Re content by the catalytic DMDTO method and for K, Ca, Mg and Cu by FAAS [11].
Two portions of dry Dowex50W×8 (1 g each) were soaked in distilled water overnight to allow theresin to swell. The swollen resin was separate from the water and was add to the 20-ml alkalineleachates containing rhenium and the main ash elements. The experiments were carrying out in 50ml polypropylene flasks with stoppers. The sorption was performing by the batch method on ashaking mаchine for 3 hours. The resin was separating from the solution by filtration through apaper filter. The resulting solutions were analysed for Re, K, Ca, Mg and Cu [11].
Results and discussion
The results of the experiments [11] showed that the leachate obtained after direct incineration of theplant mass, purified by treatment with Dowex 50W×8, contains 95.3 % of Re and only 4.7% of thesum of main ash elements. The leachate obtained after ethanol extraction of Re from alfalfa and its
purification with Dowex 50W×8 contains 98.2 % of Re and only 1.8 % of impurities of main ash
elements. The comparison of the results of the two procedures for Re extraction from the plant mass
revealed that after ethanol extraction of Re from alfalfa a higher degree of purification of the Re
containing leachate from the main ash elements was achieved than after direct incineration of alfalfa[11]. These results are in accordance with our previous study [14]. As a result of our experiments,
we developed a simple procedure for purification of the Re containing leachate from the main ash
elements such as K, Ca, Mg and Cu by cation exchange on the Dowex 50W×8 resin. NH4ReO4 is
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easily obtaining from the final solution after its alkalization with NH4OH, preconcentration byevaporation and crystallisation of NH4ReO4 [16].
Conclusions
As a result of our investigations we developed a low-cost and environmentally friendly
technological scheme for real phytorecovery of Re dispersed in the soils of ore dressing areas byalfalfa which includes:
1.

Regional investigation of Re distribution in the vegetation of the copper ore dressing areas
and finding the points with industrial importance for Re phytomining;
2. Cropping these areas with alfalfa and obtaining of Re phytoconcentrate;
3. Harvesting the alfalfa and extraction of Re from the green mass;
4. Purification of the Re containing leachate by a simple procedure developed by us andobtaining of NH4ReO4- - the commercial product of Re on the world market.
Acknowledgments:
The authors acknowledge the financial support of the National Science Fund of Bulgaria (National Centre
for New Materials UNION, Contract No DCVP-02/2/2009).

References:
1. M. M. Lasat, Journal of Hazardous Substance Research, 2: 5-25, 2000.
2. V. Sheoran, A. S. Sheoran, P. Poonia, Minerals Engineering, 22, 1007-1019, 2009.
3. O. Bozhkov, Chr. Tzvetkova and T. Blagoeva, Proceedings of the1st International
Conference on Waste Management, Water Pollution, Air Pollution, Indoor
Climate(WWAI’07), Published by WSEAS Press, ISBN: 978-960-6766-09-1, Arcachon,France, October 13-15, 2007, pp. 257-261.
4. O. Bozhkov, Chr. Tzvetkova and T. Blagoeva, Proceedings of the 2nd WSEAS International
Conference on Waste Management, Water Pollution, Air Pollution, Indoor Climate,(WWAI’08) Published by WSEAS Press, ISBN:978-960-474-017-8, Corfu, Greece,
October 26-28, 2008, pp. 262-265.
5. O. Bozhkov, Chr. Tzvetkova, L. Borisova, V. Ermakov and V. Ryabukhin, Trends in
Inorganic Chemistry, review, Vol. 9, 1-10, 2006.
6. O. Bozhkov and L.V. Borisova, Anal. Communications, 33, 133-135, 1996.
7. O. D. Bozhkov and L. V. Borisova, Intern. J. Environ. Anal. Chem, vol. 83,
N 2, 135-141, 2003.
8. O. D. Bozhkov, N. Jordanov, L. V. Borisova, Yu. I. Fabelinskii, Fresenius Z. Anal. Chem.,
321, 62- 64, 1985.
9. L. Borisova and A. Ermakov, Analytical Chemistry of Rhenium (in Russian), Nauka,
Moscow, 1974.
10. M.A. Askari Zamani, N. Hiroyoshi, M. Tsunekawa, R. Vaghar, M. Oliazadeh,Hydrometallurgy, 80, 23–31, 2005.
11. Chr. Tzvetkova and O. Bozhkov, Proceedings of the 2nd International Conference on Waste
Management, Water Pollution, Air Pollution, Indoor Climate(WWAI’08) Published by WSEAS
Press, ISBN:978-960-474-017-8, Corfu, Greece, October 26-28, 2008, pp. 82- 85.
12. Chr. Tzvetkova and O. Bozhkov, Proceedings of the 7th WSEAS International Conference on
Environment, Ecosystems and Development (EED ‘09), Published by WSEAS Press, ISBN: 978960-474-142-7, Puerto De La Cruz, Tenerife, Canary Islands, Spain, December 14-16, 2009, pp.
123-126.
13. O. Bozhkov, Chr. Tzvetkova, Proceedings of the 7th WSEAS International Conference on
Environment, Ecosystems and Development (EED ‘09), Published by WSEAS Press, ISBN:
978-960-474-142-7, Puerto De La Cruz, Tenerife, Canary Islands, Spain, December 14-16,
2009, pp. 127-131.
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14. Chr. Tzvetkova, O. Bozhkov and E. Russeva, Proceedings of the 1st International
Conference on Waste Management, Water Pollution, Air Pollution, Indoor
Climate(WWAI’07), Published by WSEAS Press, ISBN: 978-960-6766-09-1, Arcachon,France, October 13-15, 2007, 253-256.
15. N. Petrov, M. Pavlova, O. Bozhkov, Method for Extracting Rhenium and Tungsten from
Wastes of Rhenium-Tungsten Alloys, United States Patent, 4, 278, 641, Jul. 14, 1981.
Z.S. Abisheva, A.N. Zagorodnyaya, Hydrometallurgy. 63 55–63, 2002.

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3.7.
INDUSTRIAL SORPTIVE RECOVERY OF RHENIUM FROMCIRCULATING SOLUTIONS OF URANIUM IN SITU LEACHINGOPERATION
V.P. Volkov, N.M. Mescheryakov
ZAO NPO “GPS”, Moscow
npogps@mail.ru

There are many researches devoted to the problem of the incidental sorptive recovery of Rhenium
from the situ leaching solutions of Uranium. However due to the set of techno-economical reasons
they didn’t have any industrial use. Until 2002 Navoi Mining-Metallurgical Combine (NGMK) has
periodically attempted to recover Rhenium from the Ionite AMP after its striping from Uranium.
Though the very expedience of this method remains questionable for the reason of the low sorptive
capacity of AMP Ionite for Rhenium, inconvenient conditions of its regeneration (composition of
the stripping solution – 3,0 - 3,5% HNO3 + 6 - 7% NH4NO3, regenerate commodity output makes
20 volumes to one of Ionite, with 10-15 mg/l Rhenium concentration, temperature amounting 50C°) and the complexity of further extraction of Rhenium from the desorbates (2 cycles of extraction– re-extraction).
In 2003 the research workers of ZAO NPO «GPS» carried out preproduction tests of the Purolite
Int. Ltd.’ Ionite KEP-100 during the Rhenium sorption from the model solutions, imitating thecomposition of manifold after Uranium sorption from PV RU-5 NGMK solutions [1]. The results oftests show high sorptive properties of the Ionite: Rhenium capacity accounts for 1,86 mg/ml (AMP
capacity in the conditions is 0,3 – 0,55 mg/ml).
On the ground of the received results the decision was made to set up an experimental-industrial
plant on the RU-5 NGMK. It is designed to provide the test cycles of the Rhenium sorption
processes from the industrial in-situ leaching solutions and the regeneration of the Rheniumenriched Ionites.
This experimental-industrial plant was worked out by the research workers of ZAO NPO «GPS».
It was mounted by 2004. It consists of two columns, connected by the pipelines, feeding thecolumns on the poor Uranium solutions (bottom-up) and stripping (bottom-up) with corresponding
pumps and valving fittings
There were conducted 5 cycles of sorption and regeneration altogether in the column with Ionite
KEP-200. Ionite KEP-100 tests were suspended since the productivity for solutions reduced (finegranulation) and the capacity of Rhenium fell considerably in further cycles.
The composition of solutions before the sorption (concentration given in mg/L): Re – 0,95; Mo –0,56; U – 2,0; P – 44,0; Fe – 400,0; Al – 377,0; Si – 48,4; SO4 – 9627; NO3 – 54,0; pH – 2,0. Test
results are given in the table below*№ Technological properties

Unit

KEP-100 KEP-200

1
2
3
4
5
6

m3
hour
g/L
kg/m3
kg/m3
kg

5500
735
0,16
6,88
1,21
14,52

Volumes of the solution treated for one cycle
Elapsing time of a sorption cycle
Re concentration in the solution after sorption
Capacity of Rhenium-enriched Ionite
Re concentration in the end product regenerates
Quantity of Re recovered in the product regenerate* - average rates during the tests

7340
790
0,40
5,95
1,42
20,87

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The composition average rates of the product regenerates from the KEP-200 Ionite’ regeneration(concentration given in g/m3): Re – 1,43; Mo – 1,74; U – 4,1; P – 2,52; Fe - < 0,15; A; - < 0,25; Si –96,0; Cr - < 0,5; Mn - < 0,2.
According to the test results basic data was developed for the creation of the industrial plant by
mounting of two sorptive columns with 30 m3 of Ionite in each [2].
The production of the high-clean ammonium perrhenate of AP-0 brand after the launch of the firstcolumn exceeded the quantity of 3 tones.
The technology described above is protected by the patent of the RF [3].
References:
1. Report on the subject: «The development of the new technology of Re recovery from the in-situ
leaching solutions of Uranium, using the compositional extract polymer KEP-100».
Moscow. 2003, ZAO NPO «GPS» funds
2. Report on the research on the subject: «The development of the technology of Re recovery fromthe in-situ leaching solutions using the composite extract polymer KEP-100. The
development of the methods of the experimental-industrial test on a section of in-situ
leaching». By the contract of KEP-100, 30.10.2002
3. Volkov V.P, Mescheryakov N.M. et al. «The method of Rhenium recovery from solutions».
Patent of the RF № 2294392, 24.05.2005

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3.8.
RHENIUM(VII) SOLVENT EXTRACTION BY MIXTURES OFTERTIARY AMINE AND OXYGEN-CONTAINING EXTRAGENTS FROM
SULPHATE MEDIA
A.G. Kasikov, A.M. Petrova
Institution of Russian Academy of Sciences – I.V.Tananaev Institute of Chemistry and Technology of Rare Elements
and Mineral Raw Materials of the Kola Science Centre of RAS
Akademgorodok, 26а, Apatity, Murmansk reg., Russian Federation

Keywords: rhenium, solvent extraction, tertiary amine, aliphatic alcohol and ketone
Abstract
Solvent extraction of rhenium(VII) from sulphate media, involving mixtures of tertiary amines andoctyl alcohol or ketone in an aliphatic diluents, has been investigated. Increasing H2SO4
concentration from 0.5 to 7 mol/L was noted to diminish the rhenium(VII) distribution coefficients
DRe regardless of both the mixture composition and temperature. Maximum DRe values wereobserved at pH=1-2. It was found that in response to octyl alcohol addition to the extraction mixture
the DRe diminished slightly. As for octyl ketone, it somewhat promoted rhenium(VII) extraction.
The latter was probably due to different solvatation effects of alcohol and ketone on TiOA.
Introduction
Tertiary aliphatic amines R3N with hydrocarbon radicals of the С8-С10 fraction are widely used inrhenium technology. In particular, they can be turned into commercial agents to extract rhenium
from scrubbing sulphuric acid solutions of the gas purification system at copper smelters(Zhezkazganredmet, Kazakhstan).
At the same time, efforts are being made to develop new extracting compositions to improverhenium recovery. In this work, we have examined parameters affecting the process ofrhenium(VII) extraction from sulphate media by solutions of different-structured tertiary amines ina solvent containing octyl alcohol or ketone as modifiers.
Experimental
In this work, the reagents were tri-n-octylamine (TOA) solutions of the “pure” grade, a technicalgrade mixture of tertiary amines with hydrocarbon radicals of normal structure С8-С10 (TAA) or an
imported technical-grade reagent tri-iso-octylamine (TiOA) of Hostarex A324 brand (no less than
95% of the main substance and up to 5% of primary and secondary amines) in the Escaid 100
diluent with addition of 20-70 vol.% aliphatic alcohols (2-ethyl-hexanol-1) or ketone (2-octanone)of pure grade.
The extracting agent was first converted into a salt by bringing in contact with a H2SO4 solution of
the same concentration as a solution of rhenium, from which the extraction was performed. Modelrhenium-containing solutions were prepared by dissolving ammonium perrhenate in distilled water,
adding a certain amount of chemically pure sulfuric acid.
The extraction process took place in separatory funnels at a volume ratio of the organic to aqueous
phase equal to 1:25, at room temperature for 5 min, which allowed to attain equilibrium in thesystem.
Rhenium(VII) content in the aqueous phase was determined by using spectrophotometry, tracing
the changing color intensity of the rhenium(IV) thiourea complex formed in the presence of Sn(II)as reducer. The light absorption was measured with a KFK-3 photoelectric colorimeter at awavelength of λ = 390 nm [1] or by the atomic-emission method on a Plazma 400 spectrometer.
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The content of rhenium in the organic phase was calculated from the difference of its contents in the
aqueous phase before and after extraction.
Results and Discussion
The parameters essential for the process were the type and concentration of both amine andmodifier, as well as acidity of the aqueous phase. In terms of structure and extractive ability towards
rhenium, these amines can be arranged in the following series: TiOA>TOA>TAA. Most of theexperiments involved TiOA as the best reagent for rhenium(VII) extraction.
Fig.1 shows that the distribution coefficients of rhenium(VII) extraction diminish considerably as
the aqueous phase acidity increases in the interval of 0.5-6 mole/L. The latter is usually associatedwith the competitive process of sulphuric acid extraction.

5

lgDRe

4,5
4
3,5
3

1
2
3
4
5

2,5
2
1,5
1
0

1

2

3

4

5

6

7

C(H2SO4)в.ф., mole/L
Fig. 1 the effect of H2SO4 concentration and extractant composition on rhenium(VII) extraction.
Cinit.(Re)=10-3 mole/L, O/W=1/25, extractant composition, v/v %:1, ∆ – 30% TiOA+20% 2-ethylhexanol-1 in kerosene; 2, ○ – 30% TiOA in 2-ethylhexanol-1;
3,● – 5% TiOA in octanone-2; 4, ▲– 5% TiOA +20% octanone-2 in kerosene;
5, □ – 5% TiOA+20% 2-ethylhexanol-1 in kerosene.

In inter-phase distribution studies, the pH region has revealed an extraction maximum by tertiaryamines at рН=1-2 (Fig. 2). When the рН increased to 7-9, rhenium(VII) extraction by an aminealcohol mixture becomes totally suppressed. By using amine-ketone mixtures, rhenium(VII) can beeffectively extracted at рН~5-7.
lgDRe
4

1

3,5

23
2,5
2
1,5
1
0,5
0
0

1

2

3

4

5

6

7

8

9

10

pH
Fig. 2 Effect of pH and extractant composition on rhenium(VII) extraction.
Cinit.(Re)=10-3 mole/l, O/W=1/25, extractant composition, v/v % :1,● – 5% TiOA in octanone-2;2, ○– 5% TiOA+20% 2-ethylhexanol-1 in kerosene.
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It is also obvious from Fig.1 that both the type and concentration of a modifier in the extragent
affect its extractive properties appreciably. In the case of ketone as modifier, a synergetic effect wasobserved (Fig. 1, 2), and also differently directed effects of increasing modifier concentration in theorganic phase when using alcohols and ketones (Fig. 3). In the case of increasing octyl alcohol
concentration in extragent, the rhenium(VII) distribution coefficients diminished, whereas withoctanon-2, these coefficients increased.
lgDRe

2

1

Cmodif.., v/v %Fig. 3 The effect of modifier type and its concentration on rhenium(VII) extraction with a TiOA-based
extragent.
Cinit.(Re)=10-3 mole/l, O/W=1/25, extragent composition, v/v%:
1, х – 30% TiOA+2-ethylhexanol-1; 2,  – 5% TiOA+octanone-2.

The fact that alcohol and ketone influence dissimilarly the amine extraction ability may be
explained by the difference in their solvatic behavior when interacting with TiOA. Being anelectron-seeking reagent, alcohol solvates the anion part of the amine salt producing relatively
stable solvate of the (R3NH)2SO4∙2ROH [2] type, thus reducing its basicity and, consequently, its
extractive ability. Unlike alcohol, ketone is a more nucleophilic reagent solvating the electronacceptor component of the extragent, i.e. the amine salt cation. This enhances the electron densityof the amine functional group and improves its extraction ability.
Conclusions
It has been found that, by varying the modifier nature, it is possible to affect the extractive ability oftertiary amine-containing extragents. For commercial applications, mixtures of a tertiary amine ineither ketone or aliphatic alcohol can be recommended, depending on the nature and composition of
the feed rhenium-containing solution.
References
6. L. V. Borisova, A. N. Ermakov, Analytical chemistry of rhenium (Rus), Nauka: Moscow(1974).
1.
Shmidt, V.S., Solvent Extraction with Amines (Rus), Moscow: Atomizdat, 1970.

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3.9.
INTERPHASE SUBSTANCES OF RHENIUM EXTRACTION CIRCUIT ARE
A SOURCE FOR PRODUCTION OFRHENIUM AND RADIOGENIC OSMIUM
A.N. Zagorodnyaya, Z.S. Abisheva, S.E. Sadykanova
Centre of Earth Sciences, Metallurgy and Ore Beneficiation, Almaty, Kazakhstan
e-mail: alinazag39@mail.ru

Keywords: interphase substances, composition, rhenium, isotope osmium-187, technology.
Abstract:

It has been determined that the reason for the formation of interphase substances (IS) duringrhenium extraction is the presence of a black-colored fine precipitate in the feed solution. The
elemental composition of the interphase substances has been determined, including the content of
trialkylamine (ТАА). The behavior of a IS in solvent extraction technology of rhenium is studied.
The technology of complex recovery of TAA and osmium-, rhenium-containing deposit from IS
and rhenium from TAA has been developed and introduced in manufacture. The combined methodof selective recovery of rhenium from the deposit resulting in production of ammonium perrhenate
and osmium-, rhenium-containing concentrate suitable for obtaining from it of isotope osmium-187
by a known technology has been developed. It was established that in 3% rhenium and osmium is lostwith IS (from entering with the charge in copper production).

Introduction
Sorption or solvent extraction technology of rhenium recovery from solutions of Kazakhstani
metallurgical enterprises is accompanied by the formation of black sediment, which differs in theirconsistency. Sediment of sorption technology - friable, solvent extraction - the dough-like or black
oil-like [1, 2]. At the one of the copper plants in Kazakhstan, rhenium is recovered from acidic
solutions resulting from the washing of metallurgical smelter gases (sulfuric wash acid). A schematic
flow-chart consists of the following
operations:
rhenium
solvent
extraction, solid-phase stripping [3](Fig. 1).
The extractant is a mixture, %Extractant(vol.): 15 TAA, 2-ethylhexanol,and 75 kerosene. Stripping was
performed by ammonia at highratios of organic and aqueous
phases giving a basic amount ofrhenium precipitates in the formof ammoniume perrhenate, which
partly captures the extractant andmother liquor (pulp). The studyof the rhenium extraction
technology over many years has
Fig. 1. Schematic flow-chart of rhenium extraction from washdemonstrated that a black-coloredsulfuric acidfine precipitate accumulates in an
extract. At the stage of the solidphase stripping, the precipitate distributes between the salt of NH4ReO4, the mother liquor and theorganic phase. During the isolation of ammonium perrhenate from the pulp, the black precipitate is
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recovered as an independent fat dough-like or black oil-like product (hereinafter referred to asinterphase substance IS). It is established that the IS contained up to 10 % (wt.) of rhenium and 0.5% (wt.) of isotope osmium -187. The lost of rhenium and osmium with IS is in 3 % from enteringwith the charge in copper production [4].
A significant amount of IS of different consistency has accumulated in the enterprise because oflack of processing technology of IS. It was a matter of considerable interest to determine theelemental composition of this product and develop technology for it processing.
Experimental
Study of the composition of IS: for several years, samples of IS of various consistency
were taken from the ammonium perrhenate production cycle for the analysis. During this time,some processes and the composition of the raw materials had changed. This paper presents thesummarized findings of the long-term production monitoring (Tabl 1).

Table 1. Characteristic of probes
Number of probe
Technological change
1
The operation of the sulfur afterburning unit
2
None unit
3
None unit, new raw material
4None unit, new raw material

Consistency
Fat dough-likeFat dough-like
Oil-like
Oil-like

Color
Black
Black
Black
Grey

A weighed sample of interphase substance was thoroughly washed out with hot distilled water toremove rhenium-containing solution. Rhenium cleanliness was controlled by qualitative reaction
with ammonium thiocyanate [5]. Then the precipitate of IS was repulped in heptane at room
temperature at the ratio of S:L=1:20 and vacuum filtered [1]. The filtered residue was washed withthe heptane until color was eliminated. The content of TAA in IS and concentration of Re in TAA
was calculated based on the TAA concentration in heptane. After removing TAA from theprecipitate, its consistency changed to become fluffy, crumbly and easily ground. The washedprecipitate was dried until it reached the constant weight, weighed and examined with various
physicochemical methods of analysis.
The composition of IS was determined by infrared — spectroscopic, X-ray diffraction (XRD),
spectral and chemical analyses. Infrared Fourier spectrometer “Avator CsJ 370” was used forreading infrared spectra. A Bruker D8 Advance diffractometer using Co radiation at 40 kV and 35
mAwas used to performXRD characterization. The compoundswere identified based on
spectrograms and X-ray photographs according to [6, 7]. The concentrations of rhenium were
determined by the well-known methods [5].
Development of technology for processing of IS: recovery of extractant from IS was
performed by repulpation in sealed sells with a jacket, mixing was performed with a mechanicalstirrer; the temperature was supported by a thermostat. On the same set of experiments onhydrometallurgical leaching of precipitate recovered from the IS, and leaching of sintering cakewere conducted. Experiments on the sintering of the precipitate with calcium oxide (charge) was
carried out in a muffle furnace at 650 0C. The charge was prepared by thoroughly mixing of the
precipitate with CaO at a given ratio.
Results and Discussion
IS and precipitate. The samples washed by water were initially analyzed by infrared
spectroscopy. The interpretation of spectrograms demonstrated that all interphase substances
contained the following: TAA (absorption bands: 2968, 2932, 2875 cm−1); ReO4− (912 cm−1),
ReO2 and ReO3 (1400 cm−1), BiO3 (312, 430, 470 cm−1), Bi2O3 (360, 410, 450, 534 cm−1);
PbSO4 (600, 625, 969, 1055, 1108, 1170 cm−1), H2O (3440 cm−1), crystalline hydrate H2O (1616cm−1); OsO4 (960, 322 cm−1); H–N groups (3490 cm−1), C=O (1800 cm−1), C=C (1513 cm−1),
rings of aromatic hydrocarbons contained in humateions. Samples No.3 and No.4 contained
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kerosene (CH3, CH2 — 2956, 2998, 2284, 2800, 1380, 1450–1468 cm−1); sample No.4 contained[Cd(NH3)4](ReO4)2 (3339, 3263, 1598, 917, 902 cm−1], [Cu(NH3)4]Cl2 (3263, 1598, 1241 cm−1).
The presence of Hg(CH3)2 (551 cm−1) is also possible.
In the IR-spectra of precipitates washed by heptane, the absorption bands of TAA, kerosene andReO4 were absent. But they were present in the heptane solutions after washing the precipitates.
The absence of absorption bands for ReO4, and the high concentration of rhenium in TAA,
indicates that during the dissolution of the pulp, rhenium transfers to solution and is extracted by thereleased TAA. The presence of TAA and kerosene is the result of the extraction reagent captured byammonium perrhenate during rhenium stripping. When the pulp was subjected to thermal
dissolution in water or in rheniumcontaining solutions, a suspension consisting of the extraction
reagent and the fine precipitate was recovered in an independent phase. When solutions were
evaporated until the required concentration of rhenium was obtained, kerosene and heptane
volatilizes and TAA remains in solution (Table 2).
Table 2. Content of TAA and Re in of probes of IS
Fat dough-likeContent
Number of probe
1
2
3
TAA, mole in 1 kg IS
1.2
1.0
0.6
Re in TAA, g/dm3
80.0
86.2
86.1
Output of precipitate, %
35.2
13.4
20.8

Oil-like
4
0.6
75.6
18,5

The quantitative content of elements in IS was specified by chemical analyses (Table 3). The data in
Table 3. Chemical composition of IS
NumberContent, % (mass.)of probe
S
Bi
Re
Cd
Fe
Ca
Zn
Se
Pb
Hg
Si
Os
1
66
1.2 8.00 2.00 2.30 1.10 1.20 0.80 0.50 0.01 0.41 0.212
9.1
24.8 6.75 1.70 1.65 1.10 0.80 1.10 0.77 0.01 0.37 0.42
3
9.1
25.1 5.65 1.58 1.00 0.76 0.98 0.73 0.80 0.01 0.38 0.37
4
8.5
3.25 5.70 4.45 1.50 1.00 0.98 0.92 0.80 13.6 0.40 0.52
Notes: content, % (mass): Mg, Ti, Ni, Na — ≤02; Mn, Cr, K — ≤0.06; Ag, Sn — ≤0.01

As
0.45
0.28
0.28
0.42

Table 3 show that all IS are identical respect to the elements present, irrespective of some processchanges. IS, containing the whole percentages of rhenium and tenth parts percentages of osmium
could be considered as additional raw material for the production of rhenium and isotope osmium187. However, the quantitative amounts of some of the individual elements vary substantially. The
content of sulfur varies from 66 to 8.5 % (mass.); bismuth varies from 1.2 to 25.1 % (mass.);
cadmium from 1.7 to 4.45 % (mass.); mercury from 0.01 to 13.6 % (mass.).
The cause of the high content of sulfur in sample No.1 is a carryover of elemental sulfur from theafterburning unit into the gas scrubber whilst that of bismuth and mercury is caused by thecomposition of raw materials. The cause of higher content of cadmium (as a complex salt
[Cd(NH3)4](ReO4)2) is an insufficient washing of the extract and the conditions of pulp dissolution.
It is well-known that cadmium and zinc contained in the solution are extracted in the form ofchloride anions and are stripped with ammonia. The complex salt [Cd(NH3)4](ReO4)2] is white,
therefore its presence has influenced the color of sample No.4.
Based on these data, it was assumed that the precipitate comes from the leaching solution of sulfuric
acid. A careful visual examination of acid indicated on the presence of very small amounts of blacksludge in the form of a light mist.
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The content of the precipitate and its distribution generated in rhenium solvent extraction in theoriginal solution, raffinate, extract, and extraction reagent after rhenium stripping was determinedby the methods we developed [8]. Table 4 shows the average values over three years.
Table 4. Content of precipitate and its distribution through the products of rhenium recovery fromwash sulfuric acid by solvent extraction
Name of productContent, g/sm3
Recovery of precipitate, %Note
Initial solution
0.0160100.0
Content
inprecipitate: Os Raffinate
0.00148.7
0,63, Re – 10.4 %Extract
0.4732
91.3(mass.)
Extractant
0.0494
9.5
Pulp
22.921
47.5
Mother liquior
2.320034.4
As it was shown from table 4 content of precipitate in wash sulfuric acid is 0.016 g/dm3. Duringrhenium extraction 91 % of the precipitate is accumulated in the extract and its content in theextract 0.4732 g/dm3, the stage of rhenium solid phase stripping 81,8 % of the precipitate isrecovered, 47,5 % of which co-precipitates with ammonium perrhenate and 34,4 % passes intomother liquors. Its content in the ammonium perrhenate pulp is 22.921 g/dm3, in the mother liquiore-2.32 g/dm3. Content of Os in the precipitate is 0,63, Re - 10.4 % (mass). Causes of osmium,rhenium-containing sediment formation are described in [9].
Osmium-, rhenium-containing precipitate is extracted from the mother liquors by water-solublecompounds with production from them a metallic osmium isotope-187 and ammonium perrhenate
according the technology, described in [10].
Development of technology for processing of IS. Our investigations have shown that IS - avery valuable by-product with high content of isotope osmium-187, rhenium, extractant, which canbe considered as an additional source of Re and Os-187. In addition, up to 10 % of the volume ofextractant involved in the process have lost with IS monthly. The presence of the extractant in the
IS is not permit to process IS according the technology [10]. In this regard, it was necessary todevelop a universal technology permitted to recover the extractant and contained in it rhenium andproduce a powdery residue suitable for production from it ammonium perrhenate and metal
osmium-187 isotope. In the base of technology laid the ability of TAA dissolved in organic
solvents. This permit to recover TAA from IS by repulpation. When choosing an organic solvent
guided by the following criteria: time of phase separation, filtration, sediment texture, theconcentration of rhenium. Ketones, alcohols, paraffin hydrocarbons, mixtures of a paraffinhydrocarbons and alcohol in different ratios, mixture of ammonia and organic solvent, a mixture ofa solvent with polyethylene polyamine (PEPA), a mixture of the ketone with ammonia, a mixture ofa solvent with ammonia solution and PEPA were tested as solvents. The effect of S:L (1:2 ÷ 10, S weight of sample of IS, L - solvent,), duration (0.5 - 5 h) and temperature (30 - 60 0C) of
repulpation, volume ratio of ammonia to the solvent (0.5 - 4) on the process indicators by chosen
solvent has been studied. The optimal conditions that enable to extract TAA from IS and produce
powdery residue has been established. Experiments on the release of ammonium perrhenate fromammonia solution by combination of processes of evaporation and crystallization have been carriedout. Extraction of rhenium from industrial solutions by TAA, recovered from IS has been conductedunder the conditions stipulated by the technical documentation of company. The resulting crude saltof ammonium perrhenate is identical to salt of the existing technology. Multicyclical experimentson the extraction-stripping of rhenium have shown the possibility of circulation of the TAA in themain process.
A complex of experiments on the recovery of rhenium and osmium from precipitate resulting in
repulpation of IS has been performed. As it mentioned above, the rhenium and osmium are present
in precipitate as slightly soluble compounds in acid solutions (do not have oxidizing properties),and alkaline solutions. On the basis of research on the interaction of rhenium oxides and sulfides
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with hydrogen peroxide in sulfuric acid and ammonium media [11, 12] as leaching reagent was
selected aqueous solution of hydrogen peroxide. According to the experiments on the effect ofhydrogen peroxide concentration (2 - 16 mol/dm3), the ratio S:L (1:2 ÷ 20), time (1 - 6 h),temperature (20 - 90 0C) was chosen optimal conditions under which in the solution is extracted
only 80 % of rhenium, , and 40 % of osmium distilled into the gas phase. As it was established by
XRD method rhenium is found in the precipitate in the form of Bi3ReO8. The unsatisfactory resultsof hydrometallurgical methods have led to development of combined method, the essence of whichis concluded in sintering of precipitate with calcium oxide at 650 0C, followed by leaching the cakewith water (S:L = 1:4, temperature 80 0C, time (1 h). At the optimum content of calcium oxide in
the mixture in the solution is extracted 93 % of rhenium, the cake is almost completely Bi 3ReO8.
Osmium is practically completely left in the cake, from which it can be recovered by the technology[10]. Rhenium-containing solutions can be either send to the dissolution of the pulp or processedindependently with production of ammonium perrhenate. Based on the complex of conductedinvestigations theSolvent
IS
Ammonia
technology
ofprocessing of IS
REPULPATION
(Fig.
2)
was
ФИЛЬТРАЦИЯ
proposed, which
FILTRATION
was tested in pilotindustrial scale at
Precipitate
Solution
Organic
a
plant
in
To
extraction
Kazakhstan.
EVAPORATIONWASHING
Eight operations withcumulativeandCrude ammonium Mother liquor of rhenium
Washing water
current IS of different
To production of complexes
perrhenate
texture with some
Precipitat
correction of regimeerhenium saltof repulpation was
SINTERING
LEACHING
Sinterсonducted.
Solution Cake To production of osmium-187 Ammonia solutions
Fig.2. Technological flow sheet for processing of IS with production of ammoniumof all the operations
perrhenate, TAA and osmium-, rheniumcontaining precipitate
were combined andevaporated
threetimes. after cooling was obtained.
Crude ammonium perrhenate of white colour after cooling was obtained. Extractant from all
operations have been also joined, corrected for the concentration of the TAA and on the equipmentof shop in accordance with the existing technological regimes had been conducted multiple solvent
extraction-stripping of rhenium. Results for repulpation of IS presented in Table 5.
The following results were obtained: TAA and rhenium are extracted from IS almost completely. The concentration of rhenium inthe extractant is 0.026 - 0.104 g/dm3;
 concentration of TAA in the solvent is 0.117-0.287 mol/dm3;
 concentration of rhenium in an ammonia solution is 17.9 – 42.2 g/dm3; osmium 0.0025 – 0.0042;
 yield of precipitate is 10.65 - 23.5 %; rhenium content in the sediment is 2.0 - 4.64 % (mass.), Os - 0.53 – 2.0;
 the crude ammonium perrhenate with rhenium content 67.9 % (by weight) and very low
content of potassium 0.001 was obtained from ammonia solutions. The pure salt of trade
mark AR-0 was produced by recrystallization of crude ammonium perrhenate; trialkylamine selected from IS extracted and re-extracted rhenium without complications.
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Table 5. - The results of pilot-industrial scale test of technology IS processing
Organic solution

Re,
g/dm3
0.043
0.029
0.026
0.096
0.054
0.061
0.048
0.104

Ammoniasolutionconcentration,
g/dm3

Cake

conet ТААcontent,
concentration
output,in 1 kg% (mass.)
precipitate,
Os,
ТАА,
%
Re
Os
Re
Os
mol/dm3
мg/dm3mol/dm3
Content in fat dough-like, % (mass.):Re – 12,6, Os – 0,064
0.0002
0.166
0.83
24.0
0.0028
13.50
4.00
1.28
0.0001
0.179
0.86
28.8
0.0031
14.20
3.85
1.76
0.0001
0.287
1.43
35.0
0.0025
13.80
4.19
1.42
0.0002
0.206
1.03
32.0
0.0030
14.40
4.64
2.00
00001
0.127
0.84
36.6
0.0025
13.55
3.94
1.98
0.0001
0.152
0.76
42.2
0.0042
10.65
3.75
1.34
Content in oil-like, % (mass.): Re – 4,63, Os – 0,091
0.0001
0.117
0.59
27.20
0.006621.9
2.15 0.56
0.0001
0.132
0.66
17.90
0.0050
23.5
2.00
0.53

Content ofsolubleRe in IS,% (mass.)

8.00
7.20
8.75
8.00
9.15
1.55
7.55
6.71

Currently, technology of IS processing introduced into production, resulting in increasing ofrhenium recovery from wash sulfuric acid on 2 % and to reduce consumption by of TAA on 10 %.
Recovery of rhenium and osmium from precipitate by combined method will be carried out
periodically as precipitate accumulates in such quantities that capable to support the productivity ofshop equipment.
Conclusions
Qualitative and quantitative compositions of IS was determined. The technology of recovery oftrialkylamine, rhenium and osmium-, rhenium-containing precipitate from IS has been developedand implemented in production. A combined method for selective recovery of rhenium and osmium
concentrate, suitable for production of metal isotope osmium-187 according the previously
developed and implemented technology was developed.
References
1. A. N. Zagorodnyaya, Z. S. Abisheva, E. I. Ponomareva, V.V. Bobrova, A. S. Sharipova.
Kompleksnoe ispol'zovanie mineral'nogo syr'ya, 1: 52 – 31 (2000).
2. S. E. Sadykanova, A. N. Zagorodnyaya, Z. S. Abisheva, V.V. Bobrova. Abstracts of the international
conference on chemical technology, 17 - June, 2007. Moscow. - 2007, Vol. 4, p. 229 - 232.
3. A. A. Palant, I. D. Troshkina and A. M. Chekmarev; Metallurgy of Rhenium. Nauka: Moscow,
2007, 298 p.
4. A. N. Zagorodnyaya, Z. S. Abisheva, S. E. Sadykanova, V.V. Bobrova, A. S. Sharipova. Nonferrous metals, 11: 74 – 77 (2005).
5. L.V. Borisova, A.V. Yermakov; Analytical Chemistry of Rhenium. Nauka: Moscow, 1974, 319 p.
6. K., Nakamoto;. Infrared and Raman Spectra of Inorganic and Coordination Compounds. Mir:
Moscow, 1991,536 p.
7. Powder diffraction file, Search Manual. Hanawalt Method. Inorganic. International Center for
Diffraction Data. 1987.
8. S. E. Sadykanova, A. N. Zagorodnyaya, Z. S. Abisheva. Kompleksnoe ispol'zovanie
mineral'nogo syr'ya, 1: 75 – 80 (2005).
9. A. N. Zagorodnyaya, Z. S. Abisheva, S. E. Sadykanova, V.V. Bobrova, A.S. Sharipova. Hydrometallurgy
104: 308 – 312 (2010).
10. Z. S. Abisheva, A. N. Zagorodnyaya, T. N. Bukurov. Platinum Metals Review, vol. 45, 3: 132 – 135(2001).
11.
S. E. Sadykanova, A. N. Zagorodnyaya, Z. S. Abisheva. Proceedings of the international
practical conference, 18 – 19 May, 2006. Karaganda, 252 – 255.
12.
S. E. Sadykanova, A. N. Zagorodnyaya, Z. S. Abisheva, V. V. Bobrova. Kompleksnoe ispol'zovanie
mineral'nogo syr'ya, 6: 54 – 66 (2010).
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3.10.
ELECTRODEPOSITION OF RHENIUM ALLOYS IN FORM OF POWDERS
AND COATINGS FROM WATER SOLUTIONS BY MEMBRANE
ELECTROLYSIS
L. Ya. Agapova, Z. S. Abisheva, S. K. Kilibayeva, I. A. Sapukov

Centre of Earth Sciences, Metallurgy and Ore Beneficiation,(Shevchenko str. 29/33, Almaty, Republic of Kazakhstan)

Keywords: rhenium alloys, electrolytic coatings, powders, complexes of rhenium, tungsten andnickel, membrane electrolysis, microhardness
Abstract:

Alloys on the basis of refractory rhenium have a number of unique physicochemical and mechanicalproperties allowing essentially improve parameters of some devices. Homogeneous structure ofrhenium alloys obtained from water solutions by electrolysis under given conditions with properties
essentially differ from properties of these alloys produced by thermal methods. Electrochemical
processes in water solutions differ by their high efficiency and need neither aggressive reagents norhigh temperatures. The basic problem is stability of anodes. All materials, except platinum, may
decompose and contaminate deposited alloys during electrolysis. Application of ionite membranes
in electrolyzers allows to prevent of cathodic and anodic reactions’ products mixing and to obtain apure final product without application of expensive platinum electrodes. The possibility of Re-W,
Re-Ni, Re-W-Ni alloys deposition in the form of powders and coatings on the copper and steel baseplates in membrane electrolyzer with the graphite anode has been shown. As electrolytes sulfateammonium and sulfuric solutions with citric acid, sodium fluoride and glycerin additives were used.
The Re-W, Re-Ni, Re-W-Ni coatings are alloys in the form of solid solutions on Re, W and Ni base.
Alloys are nanostructured because their crystallization occurs with isolation of fine-dispersed phases
having 2-20 nanometers size of grains. Microhardness of the coatings deposited on copper plate canreach 8270 MPa for Re-Ni, 35000 MPa for Re-W, 14808 MPa for Re-Ni-W coatings depending onelectrolysis parameters. Re-W coatings corrosion resistance is higher than Re-Ni coatings corrosion
resistance.
Introduction

This paper is devoted to electrodeposition of rhenium alloys in the form of powders and coutingsfrom water solutions in conditions membrane electrolyses. Alloys of rhenium with tungsten andnickel have especially valuable properties: a fusion heat, chemical firmness at heats and are used in
the space-rocket techniques, aircraft, atomic engineering, instrument making, radio electronics [1].
The scientists in the former USSR execute the big complex of researches of physical and chemicalinteraction of rhenium with the metals formed a theoretical basis of creation of new alloys with theset properties [2-5]. The basis for carrying out of these investigations was our researches on
recycling of a technological waste of the electronic industry formed in the course of manufacture oftungsten- rhenium alloys and products them have served. This waste alkaline solutions obtained
after electrochemical processing, in our opinion, can serve as a basis of electrolyte for deposition bya method electrolyses of tungsten- rhenium coverings or powders. The electrolyses method enables
to obtain alloys of homogeneous structure with the set properties. In the case of drawing of coatings
provides uniformity of a coating, its strong coupling with the basic metal and possibility to have a
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coat layer of a necessary thickness. The properties of electrolytic alloys essentially differ from theproperties of the same alloys obtained by thermal methods. Micro hardness, plasticity, thermal
stability electrolytic alloys can be above several times [6]. It is connected by that formationelectrolytic deposits passes in no equilibrium conditions. As a result on the cathode met stable
crystal phases are formed. Many works devoted to electrolytic deposition of rhenium alloys withtungsten are known. In all these works, as a rule, for of rhenium alloys obtaining the process ofelectrolyses conduct at high density of a current (5000-20000 А/m2) with use of platinum anodes.
The electrochemical processes are highly effective in water solutions requiring neither aggressive
reactants nor high temperature conditions. The most challenging problem consists in anodes
stability. All materials, platinum excepted, may be attacked in electrolysis process resulting incontamination of deposed alloys. This problem may be solved using ion-exchange electrolyze
membranes which prevent potential mixing of cathode and anode reactions products when the superpurity alloys are produced without application of expensive platinum electrodes [7].
Experimental
Properties of electrolytes containing ions of rhenium, tungsten and nickel studied byconductometry, voltammetry, infrared spectroscopy, electrodialysis. For obtaining of rhenium
containing powders and coverings four-chamber membrane electrolyzer with graphite anode wasused. During process current density, temperature of solutions, their structure and a cathode material
were changed. As a substrate material stainless steel, copper are used. The cathode with a deposit
washed out with distilled water, dried with alcohol, weighed on analytical scales, counted a thickness ofa covering. Alloys sediments are analyzed by electron-spectroscopic, X-Ray and chemical methods.
Microhardness of rhenium containing coverings measured by microhardness meter PМТ-3, pressing a
diamond pyramid by loading of 50 or 100g.

Current dens ity, А/m2

Results and Discussion.
The introduction of additives in electrolyte pulls together potentials of metals restoration (see Table1). It does possible their joint deposition on the cathode in the metal form in an alloy.
Kinetic studying of cathodes restoration
1200
of ions Re, W and Ni from ammonium5
1
sulfate citric acid and fluoride-sulfate
24800electrolytes by themethods of3
voltampermeter(Fig.1)and
6400volumemeter has shown, that process of
7
restoration irrespective of electrolyte
0
structure is accompanied by competing
-1
-0,6
-0,2
0,2
process of allocation of hydrogen.
Potential, V
Speed of process of metals ions
restoration is defined by the chemical
Fig.1. Cathodic polarization curves on apolarization passing in concentration
Pt-electrode in Re-,W-containing solutions. The
3
and then in the phase. The speed ofelectrolyte, g/dm : 1 –5 Re; 2 – 9 W; 3 –5 Re, 9 W, 40
H2SO4; 4 –5 Re, 9 W, 40 H2SO4, , 5 NaF; 5 – 5 Re, 9 W, process, as a whole, is limited by the
80 H2SO4, 5 NaF; 6 – 5 Re, 9 W, 100 (NH4)2SO4; 7 – 5 slowest stage - electro crystallization ofRe, 9 W, 100 (NH4)2SO4, 100 citric acidcathodes sediment.

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Table 1. Measurement data on the equilibrium potential of Pt-electrode in Re-, W-, Ni- containing solutions(25оС)The electrolyte, g/dm3
Potential,
The electrolyte, g/dm3
Potential,
V (n.h.e.)V (n.h.e.)
NH4ReO4 (5 Re)+0,806 Na2WO4 (9 W)+0,441NH4ReO4 (5 Re), 100 (NH4)2SO4+0,687 Na2WO4 (9 W), 100 (NH4)2SO4+0,397
NH4ReO4 (5 Re), 100 citric acid
+0,848 Na2WO4 (9 W), 100 citric acid
+0,756
NH4ReO4 (5 Re), 100 (NH4)2SO4,+0,767 Na2WO4 (9 W), 100 (NH4)2SO4,+0,795100 citric acid100 citric acid
NH4ReO4 (5Re), 5 NaF+0,607 Na2WO4 (9 W), 5 NaF+0,459NH4ReO4 (5 Re), 40 H2SO4+0,938 Na2WO4 (9 W), 40 H2SO4+0,911NH4ReO4 (5Re), 40 H2SO4, 5 NaF+0,901 Na2WO4 (9W), 40 H2SO4, 5 NaF+0,884NH4ReO4 (5 Re), Na2WO4 (9 W), 100 +0,773 NH4ReO4 (5Re), Na2WO4 (9 W),+0,866(NH4)2SO4, 100 citric acid40 H2SO4, 5 NaF
NH4ReO4 (5 Re), 40 H2SO4, 10 NaF+0,906 8,4 H2WO4, 40 H2SO4, 10 NaF+0,659NH4ReO4 (5 Re), 40 H2SO4,+0,651 8,4 H2WO4, 40 H2SO4, 10 NaF,
+0,65010 NaF, 8,4 glycerin
8,4 glycerin
20 NiSO4, 40 H2SO4+0,673 20 NiSO4, 40 H2SO4, 40 H2SO4, 10 +0,659
NaF, 8,4 glycerin
20 NiSO4, 40 H2SO4, 40 H2SO4, 10 NaF +0,651

The formation of anion complexes of tungsten and rhenium with citric acid and sodium fluoride inammonium-sulfate citric acid and fluoride-sulfate ammonium-sulphate electrolytes was shown by
the methods of conductor meter, the IR-spectroscopy, an electro dialysis. The stekhio meter
structure of rhenium and tungsten complex ions is defined; free energy of formation and instability
constants are calculated (see Table 2). It is shown, that process of formation of complexes passes insteps through intermediate, less steady complexes. Tungsten and rhenium with citric acid andsodium fluoride form anionic complexes, presumably [WO2C6H5O7]-, [ReO3(OH)F2]2- или[ReO2(OH)(HF2-)3]-, [ReO(H2Cit)-(OH)4]2-, HWO3F2-. Tungsten Rhenium more than inclined toform complexes, and the formation of fluoride complexes of tungsten can pass through theintermediate sulfate complex, presumably [WO3SO4]H-. The fluoride complexes of rhenium andtungsten are steadier, than citric acids ones, and complexes of tungsten stronger the rhenium ones
[8].
The mechanism of cathodes restoration
Table 2. The values of the instability constants (Ki) and free
process of Re and W anions fromenergies of formation (G) complex ions of Re and W
ammonium- sulfate citric acid and
The ratio of
RheniumTungstenfluoride-sulfate
ammonium-sulfate
Me: ligand
G, kJ
G, kJ /electrolytes can be presented as follows.
in the
Ki
Ki
/ mol
mol
The surface-active cations, present atcomplex
Fluoride complexes
solutions, are adsorbed on the cathode,
1:1
3.80×10-3 13.79 1.33×10-4 22.11
facilitating the approach of anion
1:2
6.22×10-7 35.39 2.20×10-8 43.66
complexes Re and W to the cathode
1:3
2.00×10-8 43.90 3.88×10-9 47.91
First of all, at the electrode there is a
Citrate complexes
primary discharge of less strong
1:1
7.20×10-3 12.22 1.29×10-3 16.48
rhenium complexes. At decrease of their
1:2
1.33×10-4 22.11 1.90×10-6 32.62
concentration in a double layer there is a
1:3
6.22×10-7 35.38 2.38×10-8 43.47
discharge of complexes of tungsten thatis besiege, taking root in a crystal lattice of rhenium. The double layer concentration decreasing
with complex ions of tungsten leads to sedimentation rhenium and so on. Two variants ofelectrolytic obtaining of W-Re coatings of high quality on stainless steel cathode are proposed
based on the carried out experiments [9]. The first variant includes productions of these types of3
coatings from electrolytes of the following composition, g/dm : 7.2 NH4ReO4; 16.0 Na2WO4 ; 3.02
о
8.0 NaF; 30-80 H2SO4, at current density of 1000-2000 A/m and 20-25 C of solution temperature.
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According to the second variant, thin bright covers are produced from electrolyte composing of,
g/dm3: 5.0-20.0 NH4ReO4; 8.0-16.0 Na2WO4; 100 (NH4)2SO4; 100 citric acid. This electrolysis
2
process is carried out during 3 hours with graded increase of current density of 500-750-1000 А/m
per 1 hour. The glycerol additive in fluoride-sulfate electrolyte positively influences on the qualityof Re-W and Re-Ni coverings, as it was shown by our subsequent researches. The glycerol ispreferable because of its well dissolution in water, formation complexes with some metals andsurface-active properties that are why we have chose it as the additive. It is established, that influoride-sulfate and ammonium-sulfate electrolytes with glycerol additives rhenium does not form,
and tungsten and nickel form with glycerol cat ion complexes. The stehiometer structure and valuesof constants of instability of W and Ni
with glycerolTable 3. The values of the instability constants (Ki) and free energies
complexes are defined (seeof formation (G)of complex compounds of Ni and W with glycerolTable 3).The steadiness of
The ratio
NickelTungstencomplexesofglycerolof
Na2WO4·2H2O
H2WO4
increases
in
the
line:
Me: ligand(complexes
with
W
in
solutionsin theG,
G, kJ /G, kJ /Na2WO4 < complexes with W
Ki
Ki
Ki
complex
kJ /
mol
mol
in solutions of H2WO4<
molcomplexes with Ni). With
3:4
1.70·10-8 44.32
increasingof
glycerol3:6 (1:2) 2.07·10-8 43.84
concentration in solutions ofsteadinessNi-complexes
3:8
5.78·10-8 41.29
decreases, and W, on the
1:2
0.44
2.03
contrary, raises. The estimated
1:3
0.18
4.25
composition of the complexes:2+-6
Ni(Glyc)2] ;
4:2 (2:1)
2.60·10 31.86
2+[Ni(H2O)3(Glyc)3] ;4:3
2.58·10-6 31.88
2+[(H3O)3(WO4·H3O)(Glyc)3] ;2+[(H3O)2(H2WO4)2(Glyc)] .Kinetic laws of cathodes restoration Re, Ni and W from fluoride-sulfate
and ammonium-sulfate electrolytes with glycerol additives are revealed. The calculated values ofseeming energy of activation (6,9-54,6 кJ/mol) testify diffusion-kinetic mode of restoration processproceed. As a whole the speed of cathodes metals restoration process at investigated electrolytes
raises among: nickel-rhenium-tungsten. Higher speed of formation of a cathodes deposit underthese conditions is marked for rhenium, the greatest influence of the glycerol additive render for
speed of cathodes restoration of tungsten. The mechanism of process of cathodes restoration of ionsof rhenium, nickel and tungsten to alloy from fluoride-sulfate solutions with glycerol additives isoffered. First of all on the cathode cat ion glycerol tungsten and nickel complexes, and then anion
fluoride rhenium and tungsten complexes are discharged. It is established, that glycerol additives in
the fluoride-sulfate solution at parity in it of concentration rhenium, tungsten and the glycerol 1:1.2
3: (1.5-1.9) ratios (g/dm ) lead to increase of microhardness of besieged coatings [10]. The glycerol
additive influences on the quality of the coating. Its surface becomes more dense and fine-grained.
The chemical analysis of deposits of coatings has shown that the glycerol additive in fluoridesulfate electrolyte promotes increase of the maintenance of tungsten in the alloy. The results ofmeasurements of micro hardness of the Re-W-coverings besieged from fluoride-sulfate ofelectrolyte without and with additives of glycerin, and the calculated values of their thickness
depending on concentration of glycerin in electrolyte are presented in Table 4. The microhardnessof coverings Re-W (Fig. 2) besieged from fluoride-sulfate of

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electrolytes on the basis oftungsten acid (H2WO4) with theadditive of glycerol makes
35851 МPа. In the Table 5 thespeed of anode corrosion ofdepositsofcoverings
in
0
4.2
8.4
12.7
16.9
ammonium-alkaline
solutionsThickness, μm
17.24
21.77
23.08
23.86
21.51
depending on structure ofelectrolytesof
theirMicrohardness, 15407 16860 35851 32769 10946
sedimentation is shown. The
Mpa
obtained data enables to draw aconclusion on direct interrelationof the microhardness values of the coverings with their corrosion steadiness. The investigations on
Re-W coverings obtaining under the conditions of membrane electrolyses made in modeling of ReW-containing solutions. However the researches carried out by us testify to possibility of
Table 4. Effect of the glycerin added in fluoride-sulfate electrolytes
based on tungsten acid (H2WO4) on the thickness and microhardnessof deposed Re-W coatings
Glycerol concentrations in fluoride-sulfate
Re-W coatings
3
properties
electrolyte, g/dm

Table 5. Effect of electrolyte composition on the thickness, microhardness and corrosion resistance of
deposed Re-W coatings (current density 1500 А/m2, temperature 20°C, duration of electrolysis 5h)
The electrolyte, g/dm3
Re-W coatings
10NaF;
10NaF;
10NaF;
10NaF;40H2SO4
properties
40H2SO4
40H2SO4
40H2SO4
2Na2SO4;
7.2 H4ReO4;
7.2 NH4ReO4;
2Na2SO4;
7.2NH4ReO4;
8.4 H2WO4
8.4 H2WO4;
7.2NH4ReO4
8.4H2WO4;
8.4 glycerol
8.4 H2WO4
8.4 glycerol
Thickness, μm
17.24
23.08
19.28
19.48
Microhardness, MPa
15407
35851
19896
30952
Corrosion resistance,
7.18·10-5
5.7·10-5
7.22·10-5
8.04·10-5
g/sm2·minsedimentation of Re-W of coverings from the solutions obtained at recycling of W-Re of a waste of
the electronic industry. The updating of the solutions’ structure after anode dissolution W-Re ofwaste under certain conditions enables to besiege from these solutions the qualitative W-Re
electrolytic coverings at low density of a current (to 3000 А/m2). The coverings Re-Ni in conditionsof membrane electrolyses on the copper cathode fromsulfate acid ammonium-sulfate solutions with glycerol are besieged.
Under conditions of membrane electrolyses with use of notplatinum electrodes double and threefold alloys on a basis of Re as
in the form of powders, and coverings can be obtained. The densebrilliant thin coverings of Re-Ni-W on a copper substrate from citricacid ammonium-sulfate electrolytes with the maintenance in themof citric acid 100 g/dm3 at graduate increase of density with acurrent from 500 to 1000A/m2 are besieged. At the smaller
maintenance of citric acid the covering are thicker, but porous. The
expediency of carrying out of the coverings heating operation inоFig. 2. The microphotography argon atmosphere at temperature 400 С, when the corrosion
firmness leads to increase and microhardness of coverings on 8-10
of Re-W alloy surfac,% is established. By data X-ray analysis of the cathodes deposits
deposited on copper platefrom fluoride sulfuric solution represent the alloys in the form of firm solutions on the basis of Re,
with additional of glycerol

W and Ni. The firm solutions on the basis of Re have hexagonal lattice, on the basis of Ni - cubic.
In the Re-Ni-W alloys as a result of complicated isomorphic replacement of rhenium atoms on theNi and W atoms the firm solution which has hexagonal lattice is formed. The character of X-ray
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analyses enables to speak about crystallization of the Re-Ni, Re-W and Re-Ni-W alloys withallocation of the small disperse phases with the size of grains 2-20 nanometers. The size of particles
makes a great impact on microhardness that is connected with the Hall-Petcha law [6]. In crystal
coverings the growth of micro hardness with reduction of the size of grain is explained by theincrease of the total area of the borders of grains which are the obstacle for dispositions. The
crystallization of the Re-Ni alloys from ammonium-sulfate sulfate acid electrolytes occurs withallocation of small disperse phases with the size of grains of 16 nanometers, therefore themicrohardness of Re-Ni coverings is lower (7871 МPа) in comparison with the coverings on thebasis of Re-W alloys (to 35851 МPа), with the size of grains from 1,7 to 2 nanometers. For
comparison, the microhardness of pure heated Re, W and Ni makes accordingly 1300, 2100 and 1000
МPа [6].
Conclusions.
The possibility of Re-W, Re-Ni, Re-W-Ni alloys deposition in the form of powders and coatings on
the copper and steel base plates in membrane electrolyzer with the graphite anode has been shown.
As electrolytes sulfate-ammonium and sulfuric solutions with citric acid, sodium fluoride andglycerin additives were used. The Re-W, Re-Ni, Re-W-Ni coatings are alloys in the form of solid
solutions on Re, W and Ni base. Alloys are nanostructured because their crystallization occurs withisolation of fine-dispersed phases having 2-20 nanometers size of grains. Microhardness of thecoatings deposited on copper plate can reach 8270 MPa for Re-Ni, 35000 MPa for Re-W, 14808
MPa for Re-Ni-W coatings depending on electrolysis parameters. Re-W coatings corrosion
resistance is higher than Re-Ni coatings corrosion resistance. Possibility of electrodeposition fromwater solutions electrolytes of nanostructured alloys on the basis of refractory rare metals (rhenium,
tungsten) in the form of coatings with the improved constructional and physicochemical properties
was established.
References.
1. Proc.Inter.Symp.on Rhenium and Rhenium Alloys. 9-13 Feb., 1997. Orlando, Florida / Ed. B.
D. Bryskin. – Orlando (Fla.): TMS, 1997.
2. Physical and chemical properties of rhenium alloys. Ed. Е. М. Savitsky, М. А.Тylkina. –Nauka: Moskow, 1979. p. 215.
3. Е. М. Savitsky, М. А.Тylkina, A.M. Levin, Rhenium alloys in electronics, Energya: Moskow,
1980. p. 216.
4. Yu.V. Lakhotkin, A.I. Krasovskiy, Rhenium-tungsten coatings. Moskow,1989. P.120-122.
5. V.V. Povetkin, I.M. Kovenskiy, Yu.I. Ustinovschikov, Electrolytic alloys structure andproperties, Moskow, 1992, p. 255.
6. Yu. D. Gamburg, Electroplating. Guide to use, Теkhnosfera: Moskow, 2006. p. 216.
7. E.I. Ponomareva, L.Ya. Agapova, Z.S. Abisheva, S.K. Kilibayeva, S.N. Aitekeeva, Tsvetnie
metalli, 4: 39-44 (2010).
8. S.K. Kilibayeva, L.Ya. Agapova, Z.S.Abisheva, Komplexnoe ispolzovanie mineralnogo cyria,
Almaty, Kazakhstan, 3: 95-106 (2010).
9. L.Ya. Agapova, S.N. Aitekeyeva, E.I. Ponomaryova, Z.S.Abisheva, Method of rheniumtungsten coatings electrodeposition. Patent #10216, 2004, Republic of Kazakhstan.
10. L.Ya. Agapova, Z.S.Abisheva, S.K. Kilibayeva, V.V.Bobrova, Method of rhenium-tungsten
coatings electrodeposition. Patent #22227, 2010, Republic of Kazakhstan.

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3.11.
APPLICATION OF ELECTRODIALYSIS METHOD FOR HIGH PURITY
METAL RHENIUM OBTAINING
Z.S. Abisheva, L.Ya. Agapova, E.I. Ponomareva, Z.T. Abdrakhmanova

Centre of Earth Sciences, Metallurgy and Ore Beneficiation,(Shevchenko str. 29/33, Almaty, Republic of Kazakhstan)

Keywords: ammonium perrhenate, electrodialysis, membranes, rhenium acid, temperature
reduction, powder, metal rhenium
Abstract:

High-temperature reduction of ammonium perrhenate by gaseous hydrogen is widespread method
for powdery metal rhenium obtaining. Purity of metal rhenium produced by this method is generally
determined by purity of initial ammonium perrhenate obtained by re-crystallization of crude
ammonium perrhenate or by electrodialysis of its solutions. Metal rhenium produced frommarketable АR-0 grade ammonium perrhenate (weight %: Re - 69,2; K – 3.0·10-3; Na – 1.1·10-3; S< 2.0·10-4; P < 1.0·10-3; Si < 4.0·10-5; Mg – 4.0·10-5; Mn – 2.0·10-5; Al – 2.0·10-4; Fe – 6.0·10-5; Ca– 2.0·10-3; Mo – 1.0·10-4; Ni – 1.0·10-4; Cu <5.0·10-5) by method of high-temperature reduction
with gaseous hydrogen at 800-900о С contained no more than 99.981 % of the basic metal. Initialammonium perrhenate purification was carried out on industrial electrodialysis apparatus with using
specially purified water for increase of metal rhenium purity in industrial conditions. In the processof electrodialysis was obtained rhenium acid. The content of impurities in ammonium perrhenate
besieged from this acid was on 1-2 order lower than in initial salt. Metal rhenium powder, producedby high-temperature reduction with gaseous hydrogen of ammonium perrhenate, preliminary
purified by electrodialysis method, exceeds on degree (order) by basic metal content (not less than
99.9970 %) the rhenium, obtained by reduction of АR-0 grade ammonium perrhenate.
Introduction

On copper manufacture in Zhezkazgan a method of recrystallization crude ammonium perrhenate acommodity product of mark АR-0 is producted. It is thus formed rhenium containing productenriched with potassium less than 1 %. The outcome of this salt makes 6 - 10 % from a commodity
output. Earlier this salt directed to a process head on solvent extraction, and now processes byelectrodialysis method [1-3]. The electrodialysis method favourably differs by its simplicity fromknown methods of clearing [4-5]. However its use for rhenium acid obtaining restrained in theabsence of corrosion-proof anode materials. The most stable anode material is platinum, at anodepolarization in solutions of rhenium acid it is exposed to destruction and pollutes a final product.
Besides, a high cost and deficiency of platinum limit its application. In the Institute of Metallurgy
and ore Benefication (now “the Center of sciences about the Earth, Metallurgy and ore
Benefication”) the theoretical and applied researches on electrodialysis application to technologies
of Re were carried out for many years [6-8]. The device is designed and regime parameters ofrhenium acids production, the basic product for other rhenium products are worked out [7-9]. In themethod and an electrodialyzator design for high pure rhenium acid obtaining the difficulties with achoice of an anode material have been overcome at the expense of application of isolating chambers
and barrier membranes. Such design of the device enables to use the cheap anode materials
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(graphite, alloys on the basis of the lead, etc.), excludes pollution of acid by an anode material thatis the important condition for obtaining of its solutions of high purity. For expansion of the let out
nomenclature commodity rhenium production at the “Center” the investigations of metal rhenium
obtaining from commodity ammonium perrhenate АR-0 carried out by a method of its hightemperature restoration by gaseous hydrogen at 800-900оС. The obtained metal Re contained no
more than 99.981 % of the basic metal. For higher purity metal Re obtaining the initial ammonium
perrhenate of mark АR-0 was cleared from present impurity industrially on industrial installation
with use of specially cleared water.
Experimental
The investigation was carried out in a seven-chamber electrodialyzer with a graphite anode andstainless cathode. The electrodialyzer consists of three sections: first section includes anodic, firstbarrier chamber and separating them cation-exchange membrane; second – includes second barrier,concentration and buffer chambers and separating them cation-exchange and anion-exchange
membranes; third – cathodic, demineralization chambers and separating them cation-exchange
membrane. The design of the seven-chamber electrodialyzer eliminates the usage of platinum
electrodes. MK-40 and MA-40 ionite heterogeneous membranes used for this study were producedby firm “Azot” (Russia). The cation-exchange membrane MK-40 and anion-exchange membrane
MA-40 have the change capacity 2.6 meg/g and 3.8 meg/g correspondingly. Solutions ofhydrochloric acid with concentrations of 10 and 1 g/dm3 were fed into the anode and cathodechambers.. The essence of electrodialysis method of rhenium acids production consists in thefollowing. To the electrodialysator desalting chamber submit a solution of rhenium salts. The
cations of salt and impurities contained in a solution migrate under the influence of an electric
current to cathodes space, and perrhenate ions through anion exchanging membranes - to thechamber of concentration (Fig.1). The process has been made continuously. The obtained rheniumacid with certain speed is constantly deduced from the chamber of concentration to special vessel
for storage. The concentration acid degree depends on a speed of carrying over of perrhenate-ions tothe chamber of concentration. The rhenium acid should satisfy not only purity requirements, butalso concentration - not less than 20 % of Re. The more Re concentration in acid, the purer salt ofammonium perrhenate it is possible tobesiege from rhenium acid [9]. Fromobtained rhenium acid by an ammonia
solution neutralization the ammonium
perrhenate salt besieges. The salt
washed out and dried up in the portions
processed on laboratory installation forrestoration of ammonium perrhenate byhydrogen.

Results and Discussion.
The researches of the concentrated
Fig.1. Scheme of ion transport of rhenium from the desalting
rhenium acid obtaining process arechamber (6) through the buffer chamber (5 )in a cellcarried out by the electrodialysis
concentration (4) rhenium acid.
method [9]. The laws of rhenium acid
Membranes: A - anion, and K - cation.
concentrating process depending on acurrent density (Fig.2), temperature (see Table 1), rhenium concentration in an initial solution(Fig.3), speed of a channel of an initial solution for the rhenium acid concentration speed in sevenchamber electrodialyzer with ionic heterogeneous membranes МК-40 and

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1

16

2

14

2

Rate of Re transport, g/m h

2520

1890

12
1260
10
630

8

0

Specific electric power
consumption, kWh/kg Re

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

6
0

100

200

300

400

Current density, A/m2

МА-40 are defined. The reaction
temperatures of solution in the firstand second barrier chambers are
increased at 200, 300 and 400 A/m2
current densities and were on average47, 64 and 870C, respectively. To
determine optimal current density
three factors were taken into account.
They were the rate of rhenium ionstransport, specific power consumption
andmaximum
permissible
temperature of solutions in barrier
chambers.

Fig.2. Effect of current density on rhenium transport
to concentrating chamber (1) and specific electric
power consumption (2)For successful membrane operation the optimum solution temperature in electrodialyzers has not tobe over 500C. Taking into account the degree of rhenium ions' transport, the best parameters of theelectrodialysis process were obtained at 400 A/m2 current density. However, at this current density
the specific electric power consumption is high and the solutions temperature is high, requiring
significant heat removal from the system. Taking all these factors into account the optimum current
density was identified as 300 A/m2. One of the basic factors influencing transport of rhenium
through membranes in the process of electrodialysis is solution temperature. The results ofinvestigation of temperature effect on rhenium ions transport using electrodialysis of a saturated
solution of potassium perrhenate are presented in Table 1. Rhenium transport into the concentrationchamber increases significantly withincrease of temperature. However, as noted, the increase of solutions temperature higher than 500C
is undesirable because ionite
Table 1. Effect of temperature on rhenium transport formembraneselectivity
electrodialysis of potassium perrhenate solution (experiment timedecreases and mechanicalis 60 minutes)
strength is abruptly decreased.
Current
Solution
Rhenium transport toRhenium
Fall in solutions temperaturedensity,temperature,
the electrodialyzer
current2
о
to 250C and lower leads not
A/mС
concentration chamber, efficiency,
only to decrease of rhenium
g/m2 .h%ions' transport into the
250
30
114.0
6.3
concentration chamber but
250
40
169.0
9.4
also o precipitation of
250
50
389.0
22.4
perrhenate
salts
in
350
30
415.0
16.8
electrodialysis
chambers
350
40
468.0
18.8
becauseofdecreaseof their
350
50
630.0
25.2
solubility.
Solubility
of
400
30
428.0
15.0
ammoniaandpotassium
400
40
477.0
16.8
perrhenates
decreases
two400
50
640.0
22.4
fold with the decrease of thetemperature from 500C to 300C [10]. Experiments on production of rhenium acids by electrodialysis
were carried out at current density of 100 A/m2 from solutions of ammonia perrhenate within therange of 5-45 g/dm3 concentration. Effect of rhenium concentration in initial solution of ammonia
perrhenate on specific electric power consumption and current efficiency is shown in Fig. 3.
Specific electric power consumption abruptly increased and current efficiency decreased insolutions with less than 15 g/dm3 rhenium concentration. Concentration polarization, electricalresistance of solutions and quantity of heat are increased during the process of electrodialysis at low
rhenium content in solutions. Concentration polarization of membranes was not observed at
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Rhenium current
efficiency, %Specific electric power
consumption, kWh/kg Re

rhenium concentration of higher than 15-17 g/dm3. Inconsiderable increase of current efficiency anda slight decline of specific electric power consumption is only explained by increasing specificconductivity of solution and therefore by decrease of electric power consumption for heating.
Characteristics of the electrodialyzer under these conditions are near their extreme values limiting
the rate of rhenium transport from the demineralization chamber into the concentration chamber forthe given electrodialysis parameters. Thus, the best conditions of rhenium acid concentration are
obtained when the process is carried out with saturated or close to saturated solutions of rhenium
salts. However, it is necessary to note that the selectivity of ion exchange membranes is decreased
with the increase of concentration of external solution [11]. It has been identified that the optimum
conditions of perrhenic acidconcentration by electrodialysis ofammonia and potassium perrhenate
solutions are the following: 300 A/m2
50
40
оcurrent
density,
50 C
solution
2
40
30
temperatureinelectrodialyzer's
chambers, 35-40 g/dm3 rhenium
30
20
concentration in initial solution, 0.6720
100.83 volume of chamber/min flow rate
1
of initial solution in a demineralization
10
0chamber [9]. Concentration of rhenium
0
10
20
30
40
50
acid in these conditions is 300 g/dm3
Re concentration, g/l
andhigher.
However,higherconcentration of produced rhenium acidFig.3. Effect of rhenium content in initial solution ofis inadvisable because the selectivity
ammonia perrhenate on specific electric power consumption
and mechanical strength of ionite(1) and current efficiency (2)membranes
aredecreased.
The
transformation of rhenium in rheniumacid from the initial quantity rhenium
has been 99 %. The basic rhenium losses (0,2 %) with anode and cathodes chambers waste
solutions occur. The outcome on a current of rhenium has made 60 %, the expense of the electric
power on 1 kg Re - 6 кVt/h. From obtained rhenium acid by an ammonia solution neutralization theammonium perrhenate salt besieges, weights, containing. %: Re - 69,2; K<1.0·10-3; Na –1.0·10-4; S– 2.0·10-3; P <1.0·10-4; Si <1.0·10-4; Mg <1.0·10-4; Mn <1.0·10-4; Al <1.0·10-4; Fe <5.0·10-4; Ca<1.0·10-3; Mo <5.0·10-4; Cu <5.0·10-5 and corresponding ammonium perrhenate of mark АR-0. For
higher purity metal rhenium obtaining the initial ammonium perrhenate of mark АR-0 was cleared
from present impurity industrially on industrial installation with use of specially cleared water.
Produced rhenium acid contained, weight %: Re -27,5; K– 4.0·10-5; Na – 8.0·10-5; Fe – 2.0·10-4;
SO4-2-0.01; Cl—0.06; mechanical impurities were not determined. The ammonium perrhenate
besieged from this acid by ammonia contained, mass. %: Re-69.2; K<2.0·10-4; Na – 6.0·10-5;
S<2.0·10-4;P<1.0·10-3; Si< 4.0·10-5; Mg – 8.0·10-6; Mn – 4.0·10-6; Al – 1.0·10-4; Fe –5.0·10-6;Ca –3.0·10-4; Mo – 1.0·10-4; Ni <1.0·10-4; Cu <5.0·10-5. The maintenance in ammonium perrhenate ofsuch impurity as potassium, sodium, magnesium, manganese, iron were on 1-2 order lower than ininitial salt. The salt washed out and dried up in the portions processed on laboratory installation forrestoration of ammonium perrhenate. The products of high-temperature ammonium perrhenate
restoration process by hydrogen were: a powder metal of rhenium, the absorbing solutions
containing rhenium, a deposit on a quartz pipe. The extraction of rhenium in a metal powder has
made from 93.4 to 98.2 %. Rhenium transformation in absorbing solutions was from 0.07 to 0.37%. The X-ray analysis of the obtained metal powder has shown full rhenium restoration to metal
and absence of oxides in it. The maintenance of impurity in a powder metal rhenium was defined by
the quantitative spectral method. The rhenium maintenance is calculated as a difference of the
impurity sum and has made not less than 99.9962-99.9970 % (see Table 2, tests № 2-6).
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Table 2. The maintenance of impurity in metal rhenium *The maintenance,
Tests metal rhenium
weights. %
1
2
3
4
-3
-3
-3
K
9.0·10<1.0·10<1.0·10<1.0·10-35<1.0·10-36<1.0·10-3Na

2.5·10-3

3.0·10-4

3.0·10-4

7.0·10-4

1.0·10-3

3.0·10-4Ca

5.0·10-3<1.0·10-3<1.0·10-3<1.0·10-3<1.0·10-3<1.0·10-3Si

4.2·10-4

3.2·10-4

2.2·10-4

1.8·10-4

2.8·10-4

2.4·10-4Al

4.3·10-4

1.8·10-4

1.3·10-4

1.0·10-4

5.0·10-5

8.0·10-5Fe

6.0·10-5

8.0·10-5

5.0·10-5

5.0·10-5

6.0·10-5

5.0·10-5

Mg

7.0·10-4

1.8·10-4

1.0·10-4

1.5·10-4

1.7·10-4

2.0·10-4

Ni

1.0·10-4

1.0·10-4

1.0·10-4

1.0·10-4

1.0·10-4

1.0·10-4

Mo<1.0·10-4<1.0·10-4<1.0·10-4<1.0·10-4<1.0·10-4<1.0·10-4Cu

6.0·10-5

2.0·10-5

2.0·10-5

2.0·10-5

3.0·10-5

1.0·10-5

Re not less than

99.9806

99.9967

99.9970

99.9969

99.9962

99.9969*1 test metal rhenium is obtained from ammonium perrhenate of mark АR-0;
2-6 tests metal rhenium are obtained from the cleared ammonium perrhenate.

Thus, electrodialysis clearing branded ammonium perrhenate АR-0 before its high-temperature
restoration by gaseous hydrogen enables to raise 10 times cleanliness of the obtained powder ofmetal rhenium.
Conclusions.
The seven-chamber electrodialyzator and technology of electrodialysis clearings, concentrating andobtaining of rhenium containing products (rhenium acid, perrhenate salts) from industrial rhenium
containing solutions are developed [12-13]. The device design enables to use the cheap anodematerials (graphite, alloys on the basis of lead, etc.), excludes pollution of rhenium acid by anodematerial that is the important condition for the obtaining solutions of high purity. The technology ofrhenium acid electrodialysis obtaining has been introduced in manufacture at Zhezkazgansky
copper factory in 1991 and it functions at the present time. The electrodialysis method for obtainingof a commodity output from sub-standard ammonium perrhenate which went earlier to a process
head is used. The rhenium maintenance in a sub-standard product fluctuates from 66.5 to 69.2 %,potassium - from 0.1 to 0.85 %. From these products by electrodialysis method the rhenium acidwith rhenium concentration from 25.5 to 30.5 %, potassium - less than 0.001 % is made. The
transformation of rhenium in rhenium acid from the initial quantity rhenium was 99 %. The basic
rhenium losses (0.2 %) with anode and cathodes chambers waste solutions occur. The outcome on acurrent of rhenium has made 60 %, the expense of the electric power on 1 kg Re - 6 кVt/h. The
optimum conditions of electrodialysis rhenium acid concentration process conducting from theammonium perrhenate and potassium solutions are: the density of a current - 300 A/m2,
temperature of solutions in electrodialyzators chambers - 50ºС, rhenium concentration in an initialsolution - 35-40 g/dm3, speed of an initial solution channel in the desalting chamber – 0.67 -0.83
volumes/minutes. Under these conditions the 300 g/dm3 and above of rhenium acid concentration isreached. Metal rhenium produced from marketable АR-0 grade ammonium perrhenate by methodof high-temperature reduction with gaseous hydrogen at 800-900оС contained no more than 99.981% of the basic metal. Metal rhenium powder, produced by high-temperature reduction with gaseoushydrogen of ammonium perrhenate, preliminary purified by electrodialysis method, exceeds on
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011degree (order) by basic metal content the rhenium (not less than 99.9970 %), obtained by reductionof АR-0 grade ammonium perrhenate.
References.
1. Z.S.Abisheva, A.N. Zagorodnyaya, N.S.Bekturganov, Hydrometallurgy, 109(N 1-2): 1-8(2011).
2. Z.S.Abisheva, A.N. Zagorodnyaya, Tsvetnie metalli, 5: 70-73 (2005).
3. Z.S. Abisheva, E.I. Ponomareva, L.Ya. Agapova, A.M. Bikineev, Z.T.Abdrakhmanova,
Tsvetnie metalli, 5: 73-75 (2005).
4. K.V. Marunova, M.A. Stepanova, Rhenium. Chemistry, technology, analysis, М.: Nauka, 1976,
P. 87-89.
5. K.V. Marunova, A.V. Stepanov, Tsvetaya metallurgiya, 18: 25-27 (1977).
6. N.A.Chokanov, A.M. Bikineev, L.V. Olenina, M.T. Dgumagaziev, Komplexnoe ispolzovanie
mineralnogo cyria (Combine usage of mineral resources), Almaty, Kazakhstan, 11: 91-93(1988).
7. S.N. Orazbaev, I.Ya. Sadchikov, Ch.T. Masenov, E.I. Ponomareva, Komplexnoe ispolzovanie
mineralnogo cyria, Almaty, Kazakhstan, 10: 57-61 (1990).
8. E.I. Ponomareva, A.M. Bikineev, Z.S.Abisheva, L.Ya. Agapova, News of Science of
Kazakhstan. Express information. Series: The development of modern science. The future ofscience. Almaty, Kazakhstan, 3: 35-36 (1996).
9. L.Ya Agapova., E.I. Ponomareva , Z.S. Abisheva, Hydrometallurgy, 60: 117-122 (2001).
10. K.B.Lebedev. Rhenium (in Russian). Metallurgizdat, Moscow ( 1963) 208 p.
11. Demineralization by electrodialysis, Edited by J.R.Wilson. Butterworths scientific publications,London (1960) 351 p.
12. L.Ya Agapova., Z.S. Abisheva, Z.T.Abdrakhmanova, T.N. Bukurov, Patent RK № 15026,
Method of producing metal powder of high purity rhenium, publ. 15.09.2007, Bulletin of
Inventions № 9.
13. A.M. Bikineev, Z.S.Abisheva, E.I. Ponomareva, L.Ya. Agapova, V.V. Bobrova, Patent RK №
20323, Method for production of rhenium acid in multiple electrodialyzers, publ. 17.11.2008,
Bulletin of Inventions № 11.

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3.12.
THE ELECTROLYTIC SUBSIDENCE OF RHENIUM
FROM ACID ELECTROLYTES
E.A. Salahova, V.A. Majidzade, F.S. Novruzova, A.F. Qeybatova, P.E. Kalantarova
M. F. Nagiyev Institute of Chemical Problems of Azerbaijan NAS
e-mail: elza_salahova@mail.ru

The future development of science and technology is possible through the study of materials
with new features and development of new equipments that would meet up-to-date requirements
based on these materials. From this view point the electrochemical acquisition of rhenium covers isof great importance. The fact that rhenium has high melting temperature and anti-corrosion
durability allows utilizing these covers in various fields of modern technology. There are numerous
electrolytes for the subsidence of rhenium in acid solutions. The main feature of the below abstract
include the methods on the electrochemical acquisition of thin layers of rhenium covers fromvarious electrolytes, as well as the selection of the optimal regime and electrolyte for the utilizationof the acquired covers in the technology. For this purpose the process of the electrolytic subsidenceof rhenium from sulfate, chloride-sulfate and chloride-borate solutions has been studied through theapplication of modern electrochemical methods. Platinum, rhenium and copper electrodes havebeen utilized as cathodes and platinum electrode has been utilized as anode; silver-chlorine
electrode has been utilized as comparison electrode. The affects of thickness, temperature, acidity ofsolution, currency density, thickness of active surface elements, change speed of the potential,
stirring, etc. on the process of electrolytic subsidence of rhenium have been studied. Through thecontrolled potential and cycle polarization curves revealed that the rhenium reduction in sulfate andchloride-sulfate solutions happens in several stages alongside with the acquisition of interim
products (Re oxides). In this regard, each stage is characterized with certain electrode potential.
Because rhenium reduction happens in acid environment the potential grade of its reduction depend
upon the acidity as well. The impact of the electrolytic acidity on the electrolytic subsidence process
shows that as the acidity increases the interim elements passivate the surface of the electrode tocertain degree which hinders the subsidence of rhenium. With the change of the acidity of theelectrolyte the yield of rhenium as per currency changes as well and its value ranges between 5060%. In order to clarify the kinetic and mechanical features of the subsidence process the cathodeand anode curves of rhenium were drawn and their nature of their polarization in the given
electrolytes was studied. It was determined that under smaller values of the currency rhenium
subsides through electrochemical polarization, under the barrier currency through diffusion andunder next densities through mixed polarization.

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3.P1.
SORPTION RECOVERY OF RHENIUM FROM ACIDIC SULFATE AND
MIXED NITRATE-SULFATE SOLUTIONSCONTAINING MOLYBDENUM
A.A. Blokhin1, E.E. Maltseva1, М.А. Pleshkov2, Ju.V. Murashkin1,
M.A. Mikhaylenko3
1

Saint-Petersburg State Institute of Technology (Technical University),Saint-Petersburg, blokhin@list.ru;
2
Science Research Center Hydrometallurgy, Saint-Petersburg,
pleshkov@gidrometall.ru;
3
The Purolite representative office in the CIS, Moscow, purolite_mm@co.ru

Keywords: rhenium, molybdenum, molybdenites, sulfuric acid, nitric acid, solutions, anion
exchange resins, sorption, stripping, separation, concentration

Abstract:
The possibility of rhenium recovery from the molybdenite concentrates processing solutions
by means of macroporous and gel anion exchange resins Purolite A170 and Purolite A172 (referredbelow as A170 and A172) has been investigated. It has been found, that A170 macroporous resin,unlike A172 gel resin, loaded both rhenium and significant amounts of molybdenum. Due to thiseffect, the rhenium capacity of A170 lower than that of А172 by 20–30% on terms of the sorption
from the molybdenum containing solutions. At the same time, ammoniac solutions readily striped
rhenium from A170 resin for any resin saturation of rhenium, as in the case of A172 resin
acceptable stripping occurred only for high resin saturation of rhenium. Rhenium stripping was notcomplete when low rhenium saturation of A172 resin obtained. Therefore, A172 resin is proposed
for the rhenium recovery from the acidic sulfate solutions from the roasting gas treatment system,
and A170 is proposed for the rhenium recovery directly from the pregnant solutions of autoclave
leaching molybdenite concentrates with nitric acid. Both A170 and A172 resins are applicable forthe secondary concentration of rhenium from primary eluates if optimal pH conditions would be
provided. Above recommendations have been experimentally proved on the model and real
solutions.
Introduction
Molybdenites are the richest natural source of rhenium. Oxidizing roasting and leaching in
nitric acid (usually pressure leaching in the presence of oxygen) are the most common ways for the
molybdenite concentrates processing [1]. Acidic sulfate solutions from the roasting gas treatment
system contain, g/l: Re – 0,3–0,7; Mo – 3–6; Cu, Zn, Fe – in 1–2; H2SO4 50–120. Pregnant
solutions from the nitric acid pressure leaching contain, g/l: Re – 0,01–0,04; Mo – 8–15, Fe, Cu, Zn– in 2–5; H2SO4 100–150; HNO3 10–30.
Preliminary experiments have shown that iron and nonferrous metals did not affect therhenium sorption from the acidic solutions with anion exchange resins. While, at the same
conditions molybdenum is readily absorbed with the resin, and may essentially decrease rhenium
loading. Therefore, rhenium and molybdenum separation is the main problem in the processing of
the solutions involved.
The possibility of rhenium recovery from the molybdenite concentrates processing solutions
by means of macroporous and gel anion exchange resins Purolite A170 and Purolite A172 has been
investigated.

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Experimental

The anion exchange resins preliminary were converted to SO42--form. The experiments on
studying the sorption and stripping of rhenium were carried out in the static and dynamic
conditions.
Тhe determination of the values of the rhenium and molybdenum capacities of the anion
exchange resins (Q) and the distribution coefficients (D) of these metals was carried out by bathequilibration. Samples of the anion exchange resins (0,2 g in a count on mass of the absolutely dry
resin) were treated by 20 ml of a solution of one or another composition. The mixture was shaken
for 48 h until equilibrium was attained. Then the rhenium and molybdenum concentrations in thesolution were determined. The amount of adsorbed metals was determined from the difference
between their initial and final concentrations. The values of mass capacity of the anion exchangers(mg of rhenium or molybdenum on g of dry the anion exchanger) were counted taking into accountthe specific volume of the anion exchanger on the values of by volume capacity (mg of rhenium or
molybdenum on ml of the swelled anion exchanger). In a number of experiments the values of themolybdenum capacity of the anion exchangers were determined parallel on the analysis ofdesorbates. Samples of the anion exchangers after the saturation were separated from workings
solutions, carefully washed with distilled water and treated by 20 ml of the 1 M NaOH solution
containing 1 mole/l of NaNO3. The mixture was shaken for 48 h. Then the rhenium andmolybdenum concentrations in the desorbates were determined.
The D values were calculates in the usual manner.
`
In the stripping experiments after the resin reached equilibrium with the solution, it was
separated from the solution and washed with distilled water. The washed resin was then strippedusing 6 M ammoniac solution. Both the equilibrium solution and the stripped solution were sampled
and analysed.
The experiments in the dynamic conditions were carried out in a glass column with a bed
volume (BV) of 20 ml and H : D = 10 : 1. The flow rate maintained about 1,0 bed volumes per hour
(BV/h) during sorption and 0,5 BV/h during stripping.
The concentrations of rhenium and molybdenum were determined by photocolorimetricmethods [2, 3] on the photoelectric colorimeter CFC-2MP. In column experiments with a realpregnant solution of nitric acid pressure leaching of molybdenite concentrate the rhenium andmolybdenum concentrations were determined by atomic-emission method on the Thermo ScientificiCAP 6200 ICP Spectrometer.
Results and Discussion
1. Preliminary study
1.1. Sorption
The presence of molybdenum in acidic sulfate solutions did not remarkably affect thesorption of rhenium with А172 gel resin and resulted in decrease of rhenium loading in the case of
А170 macroporous resin (Figure 1).

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DRe
900

A172

800
700
600
500

A170

400
300
200
100
0
0

1

2

3

4

5

6

7

8

CMo, g/l

Figure 1. Molybdenum influence on rhenium sorption from the solution,
containing 1M H2SO4 with initial rhenium concentration of 1 g/l
Re

lgDRe

lgDMo

3,6
A172
3,3
A170
3,0
2,7
2,4
2,1
1,8
1,5
1,2
0,9
0,6
0,3
0,0
0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0

Mo

2,2
2,0
1,8

A170

1,6
1,4
1,2
1,0
0,8

A172

0,6
0,4
0,2
0,0
0,0

0,2

0,4

0,6

0,8

1,0

1,2

CH SO , mole/l
2

1,4

1,6

1,8

2,0

CH SO , mole/l

4

2

4

Figure 2. The influence of H2SO4 on the rhenium and molybdenum distribution(Initial rhenium concentration of 0,6 g/l, molybdenum of 2 g/l)

lgDMo

lgDRe
3,5

A172

3,0
2,5

1,5

A170

0,5

1,5

0,0

1,0

-0,5

0,5

-1,0

0,2

A170

1,0

2,0

0,0
0,0

Mo

2,0

Re

0,4

0,6

0,8

1,0

CHNO , mole/l
3

-1,5
0,0

A172

0,2

0,4

0,6

0,8

1,0

CHNO , mole/l3

Figure 3. The influence of HNO3 on rhenium and molybdenum distribution(initial rhenium concentration of 0,1 g/l, initial molybdenum concentration of 2 g/l,
sulfuric acid concentration of 1 mol/l)A170 macroporous resin, unlike A172 gel resin, loaded both rhenium and significant amountsof molybdenum. Rhenium loading capacity slightly depended upon sulfuric acid concentration bothfor macroporous and for gel resin, with essential molybdenum capacity decreasing in the case of
А170 macroporous resin (Figure 2).
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For any resin tested both rhenium, and molybdenum loading capacity decreased in thepresence of nitric acid, being more distinguish for molybdenum (Figure 3).
1.2. Rhenium strippingAmmoniac solutions readily striped rhenium from A170 resin for any resin saturation ofrhenium, as in the case of A172 resin acceptable stripping occurred only for high resin saturation ofrhenium. Rhenium stripping was not complete when low rhenium saturation of A172 resin obtained(Figure 4).
Elution rate, %
100

A170

80

A172
60

40

20

0
0

5

10

15

20

25

30

35

40

45

ERe, mg/mL

Figure 4. The dependence of the rhenium elution rate upon the resin saturation(Stripping solution: 6M ammonia)

2. Rhenium recovery from acidic sulfate solutions from the roasting gas treatment system
Obtained adsorption and elution curves for rhenium and molybdenum are shown on the
Figures 5 and 6, and some calculated characteristics are in the Table 1.
According to the data given А172 gel resin is more suitable for the rhenium recovery fromthe solutions involved.
CRe, g/l
0,50
0,45

A170

A172

0,40
0,35
0,30
0,25
0,20
0,15
0,10
0,05
0,00
0

20

40

60

80 100 120 140 160 180 200 220 240 260

V, BV

Figure 5. Rhenium adsorption curves from the model solution containing Re of 0,5 g/l, Mo of 4 g/l andH2SO4 of 100 g/l

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C, g/lC, g/l

A170

40

A172

45

Re

40

35

35

Mo

30

30

25

25
20

20

Re

15

15

10

10

5

5

Mo

0

0
0

1

2

3

4

5

6

7

0

8

1

2

3

4

5

V, BV

6

7

8

V, BV

Figure 6. Rhenium and molybdenum elution curves by 6M ammonia

To reduce molybdenum content in the rhenium eluates a selective stripping of molybdenum
using saline solutions was proposed. Rhenium and molybdenum elution curves from preprocessed
resin one can see on the Figure 7, and some calculated characteristics are in the Table 1.
C, g/l 40
35

Re

30
25
20
15
10
5

Mo
0
0

1

2

3

4

5

6

7

8

9

V, BV

Figure 7. Rhenium and molybdenum elution curves from A172 loaded resin by 6M ammonia after
molybdenum scrubbing
Table 1. Sorption and elution characteristics of rhenium and molybdenum recovery according to the column
experiment with A170 and A172 resins

Resin
А170
А172
А172

Re in loaded resin,mg/ml resin
64,0
98,9
97,3

Mo scrubbing,mg/ml resin
Re
Mo
—
—
—
—
3,0
16,3

Re striping,mg/ml resin
Re
Mo
63,3
68,7
94,4
23,5
87,1
1,1

Re:Mo ratio
feed
0,125

eluate
0,92
4,02
79,2

Re

K Mo
7,36
32,2
633,5

3. Rhenium recovery from pregnant solutions of molybdenite concentrates nitric acidpressure leaching
A basic difficulty in rhenium recovery from pregnant solutions of molybdenite concentrates
autoclave pressure leaching in the presence of nitric acid is caused by low rhenium concentrationand depressing effect of nitrate ions on the rhenium adsorption. As one can see on the Figure 8, bothresins appeared to be quite rhenium selective, with А172 gel resin having higher rhenium capacity.
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QRe, mg/ml

A172

8

0,15 M HNO3

QRe, mg/ml
0,3 M HNO3

7

A170

7

0,15 M HNO30,3 M HNO3

6

60,5 M HNO3

50,5 M HNO3

5

4

4
3

3
2

2

1

1

0
0

5

10

15

20

25

30

35

40

0
0

5

10

15

20

25

30

35

40

45

50

55

60

СRe, mg/l

СRe, mg/l

Figure 8. Rhenium adsorption isotherms from mixed nitrate-sulfate solutions containing Mo of 8 g/l andH2SO4 of 100 g/l

Unfortunately, rhenium stripping was found to be incomplete when low rhenium saturation ofA172 resin obtained (Table 2).
Therefore, just A170 resin was proposed for the direct rhenium recovery from pregnant
solutions of molybdenite concentrates autoclave pressure leaching in the presence of nitric acid.
Table 2. Rhenium elution characteristics for A170 and A172 resins

Resin
А170
А172
А172

Re in loaded
resin, mg/ml
resin
5,36
5,24
5,24

Stripping conditions

Re in eluate,
mg/ml resin

Elutionrate, %

6 М ammonia, 19°С
6 М ammonia, 19°С
6 М ammonia, 50°С

5,13
1,83
2,55

95,7
34,9
48,7

Re in striped
resin, mg/ml
resin
0,23
3,41
2,69

In column experiments we used A170 resin and a real pregnant solution of nitric acidpressure leaching of molybdenite concentrate. It contained, g/l: Re– 0,0096; Mo– 9,0; Fe– 1,3; Cu–
0,5; H2SO4 ~ 100; HNO3 ~ 10; Se ~ 0,015. Obtained adsorption and elution curves for rhenium andmolybdenum are shown on the Figures 9 and 10, and some calculated characteristics are in the
Table 3.

Figure 9. Rhenium adsorption curves from a real solution for A170 resin
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CRe, mg/l

101000

V, BV (Mo)8

6

CMo, g/l
4

2

900

0

40
36

Mo

800

32

700

28

Re

600

24

500

20

400

16

300

12

200

8

100

4

0

0

1

2

3

4

5

6

7

8

9

0
10

V, BV (Re)Figure 10. Rhenium and molybdenum elution curves from loaded A170 resin by 7 M ammonia

Rhenium concentration in the eluates appeared to be low. So, the second stage of rhenium ionexchange concentration following by the ammonia distillation from the primary eluates is needed
for the rhenium recovery. Both A170 and A172 resins are applicable for the secondary rhenium
concentration from primary eluates, if optimal pH conditions would be provided (Figure 11, 12;
Table 3).
CRe, g/l

0,50

A170

0,45

A172

0,40
0,35
0,30
0,25
0,20
0,15
0,10
0,05
0,00
0

10

20

30

40

50

60

70

80

90

V, BV

Figure 11. Re and Mo adsorption curves on secondary rhenium concentration(Initial Re concentration of 0,5 g/l, Mo of 15 g/l, and NH4NO3 of 0,35 mole/l)

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C, g/lC, g/l

A170

11

A172

11

10

10

Re

9
8

8

7

7

6

6

5

5

4

4

3

3

Mo

2

2

1

1

0
0

1

Re

9

2

3

4

5

Mo

0

6

0

V, BV

1

2

3

4

5

6

7

V, BV

Figure 12. Re and Mo elution curves on secondary rhenium concentration by 6 M ammonia
Table 3. Sorption and elution characteristics of rhenium and molybdenum recovery according to thecolumn experiment with A170 and A172 resins

Stage
I
II
Σ I+IIIIΣ I+II

Resin
A170
A170
A170
A172
A170(I)+
A172(II)

Re in loaded
resin, mg/ml
resin
2,0
31,5
–
34,8
–

Re striping,mg/ml resin
Re
Mo
1,85
51,0
28,5
3,9
–
–
30,1
0,17
–

–

Re:Mo ratio
feed0,00107
0,033
–
0,033

eluate
0,036
7,3
–
177,1

–

–

Re

K Mo

KRe conc.

33,9
221,2
6822
5365

37,5
10,36
540
9,26

165514482

Conclusions
The possibility of rhenium recovery from the molybdenite concentrates processing solutions bymeans of macroporous and gel anion exchange resins Purolite A170 and Purolite A172 has been
investigated. As a result A172 resin is proposed for the rhenium recovery from the acidic sulfate
solutions from the roasting gas treatment system, and A170 is proposed for the rhenium recovery
directly from the pregnant solutions of autoclave leaching molybdenite concentrates with nitricacid. Both A170 and A172 resins are applicable for the secondary concentration of rhenium fromprimary eluates if optimal pH conditions would be provided.
References

1. A.N. Zelikman, B.G. Korshunov. Metallurgiya redkih metallov. Moscow: Metallurgiya, 1991.
432 p.
2. L. V. Borisova, A.N. Ermakov. Analiticheskaya chemia reniya. Moscow: Nauka, 1974. 319 p.
A.I. Busev, V.G. Tintsova, V.M. Ivanov. Rukovodstvo po analiticheskoy chemii redkih
metallov. Moscow: Chemia, 1978. 423 p.

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3.P2.
RHENIUM PHYTOMINING BY ALFALFA (MEDICAGO) FROM SOILS OF
ORE DRESSING REGIONS AT LABORATORY CONDITIONS
Christina Tzvetkova1, Ognyan Bozhkov1 and Ludmila Borisova2
e-mail:icho68@abv.bg
Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences,
Acad. G. Bontchev Str., bl. 11, Sofia, 1113 Bulgaria
2
Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygina str. 19,
Moscow, 119071 Russia
1

Keywords: rhenium, phytomining, alfalfa, soils, copper mines
Abstract:
Rhenium is dispersed in surface environment of copper ore dressing and work processing regions
as a ReO4- and volatile Re2O7 that is converted to ReO4- in contact with water. The unique propertyof rhenium to accumulates as a ReO4- in the green over ground parts of vegetation could be used
for its collection from the environment of these regions, i.e., for phytomining. The present work
deals with the application of discovered by us Re hyperaccumulator -alfalfa (Medicago) forcollection of dispersed Re from the soil near the depot of Cu concentrate of the mine Asarel –Bulgaria. Laboratory experiments for Re extraction with alfalfa from soil of mine Asarel werecarried out. The results showed that 35 days after sowing the Re concentration in alfalfa reachedthe maximum value of 4870 g Re/t ash. Simple calculations show that 1t alfalfa ash could beobtained from 2937 m2 alfalfa crop and that the profit for the producers will be around 20 000 $.
Moreover phytomining of Re with alfalfa leads to remediation of exhausted soils of mine regions.
Introduction
Current technologies for the production of rhenium containing concentrates and subsequentrhenium recovery are not effective enough. During these processes, part of the rhenium is lost anddispersed as ReO4- in the waste industrial solutions and waters and as volatile Re2O7 that isconverted to ReO4- in contact with water in the surrounding soils. The unique property of rhenium
to accumulate in the green over ground parts of vegetation could be used for collection of therhenium scattered in the environment of copper ore dressing and work processing regions, i.e., forphytomining [1,2]. The best plant hyperaccumulators of Re discovered by us at laboratory
conditions are alfalfa (Medicago) containing 4.66 % Re in the dry mass and white clover (Trifolium
repens) – 3.51 % Re in the dry mass [3, 4].
The present work deals with the application of alfalfa (Medicago) for collection of the rhenium
scattered in the soil near the depot of Cu concentrate of the mine Asarel - Bulgaria.
Experimental
We took the soil sample near to the depot of copper concentrate of mine Asarel. The bio available form ofrhenium in the surface environment is the soluble perrhenate ion (ReO4-). An aqueous extract from the soils
was made for determination of Re [5]. The pH of the leaching aqueous solution was 8.5-9.0. This indicatesthat the soil is alkaline. The Re content in the leaching solution was determined by the highly selective andsensitive catalytic method with N, N-dimethyl-dithiooxamide (DMDTO) developed by us [6]. The results of
the analysis show that CRe= 5µg Re/ g dry soil. The further experiments were carried out as follow:
One plastic plate with soil sample was planted with alfalfa and regularly watered. Three days after seeding,the alfalfa sprouted and further developed small leaves within thirty days. Probably the soil
was very exhausted and the plant did not get sufficient nutrient ions for its growth. However, the green mass
was harvested on 10 and 35 days after sowing and dried at 70oC in an oven. The dry plant mass was exactly
weighed and incinerated at 480o C in a crucible furnace. Re was extracted from the ash by an alkaline
solution [7]. The content of Re was determined by the DMDTO method [6]. The results are shown in Table 1.
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Results and discussion
The results of table 1 show that, although the alfalfa species is undeveloped, it accumulates extracts
and concentrates Re from contaminated soil. The Re concentration in alfalfa (4869 μg Re/g ash) exceed
around three times that in acacia leaves (1682 μg Re/g ash) growing on the same soil [8]. The undeveloped
alfalfa may be due to the exhausted soil and its alkalinity. It is known that the optimum pH range of soil for
alfalfa growing is pH= 6-7 [9], while theTab.1. Rhenium accumulation by undeveloped alfalfa
exhausted soil from mine Asarel is withfrom exhausted soils of mine Asarel (CRe=5µg Re/ g dry soil
pH=8.5-9. The laboratory experiments
Plant
Sampling CReF
CReFshow that the Re phytoextraction from
species time after μg Re/g
μg Re/g ash
contaminated and exhausted soils from ore
sowing dry mass
dressing region is really possible. For field
experiments agronomists should be
alalfa10 days 593
119
2778
556
consulted with a view to optimize thealfalfa 35days
1381
276
4869
974
conditions for development of alfalfa. This
includespreconditioningofsoil,
F – Enrichment factor = CRe in plant/ CRe in soil
optimization of the depth of ploughing, thequantity of seed per 1000m2, the depth ofsowing, and the quantity of fertilizer,
watering and other [9]. Our opinion is that the well developed alfalfa will accumulate more rhenium.

Conclusions
We can conclude that:
1. Alfalfa is suitable for real collection of scattered rhenium from soils of ore dressing regions.
2. Simple calculations show that 1t alfalfa ash could be obtained from 2937 m2 alfalfa crop.
With Re concentration = 4870 g Re/t ash at a current price of Re = 4 500$/kg, the profit forthe producers will be around 20 000 $, after deducting the cost of production.
3. Cultivation of alfalfa on the exhausted soils of mine regions leads to their remediation. For
example, after being sowed with alfalfa for three years, 1000 m2 soil was enriched with 7 kg
P2O5, 12 kg Ca, 20 kg N2 and 9 kg K2O. This exceeds the average norm for fertilization ofagriculture soils [10].
4. Application of Re phytomining in ore dressing regions would result in remediation andpurification of the environment in these districts.
References
1. O. Bozhkov, Chr. Tzvetkova and T. Blagoeva, Proceedings of the1st International Conference on

Waste Menagement, Water Polution, Air Pollution, Indoor Climate(WWAI’07), Published by
WSEAS Press, ISBN: 978-960-6766-09-1, Arcachon, France, October 13-15, 2007, pp. 257-261.
2. O. Bozhkov, Chr. Tzvetkova, L. Borisova, V. Ermakov and V. Ryabukhin, Trends in Inorganic Chemistry,
review, 9, 1- 10, 2006,.

3. Chr. Tzvetkova and O. Bozhkov, Proceedings of the 2nd International Conference on Waste
Management, Water Pollution, Air Pollution, Indoor Climate(WWAI’08) Published by WSEAS Press,
ISBN:978-960-474-017-8, Corfu, Greece, October 26-28, 2008, pp. 82- 85.
4. Chr. Tzvetkova and O. Bozhkov, Proceedings of the 7th WSEAS International Conference on
Environment, Ecosystems and Development (EED ‘09), Published by WSEAS Press, ISBN: 978960-474-142-7, Puerto De La Cruz, Tenerife, Canary Islands, Spain, December 14-16, 2009, pp.
123-126.
5. O. Bozhkov, Chr. Tzvetkova, Proceedings of the 7th WSEAS International Conference on
Environment, Ecosystems and Development (EED ‘09), Published by WSEAS Press, ISBN: 978960-474-142-7, Puerto De La Cruz, Tenerife, Canary Islands, Spain, December 14-16, 2009, pp.
127-131.
6. O. Bozhkov and L.V. Borisova, Anal Communications, 33, 133-135, 1996.
7. Ognyan D. Bozhkov and Luydmila V. Borisova, Intern. J. Environ. Anal. Chem., 83, N 2, 135-141, 2003.
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8. O. Bozhkov, Chr. Tzvetkova and T. Blagoeva, Proceedings of the 2nd WSEAS International
Conference on Waste Management, Water Pollution, Air Pollution, Indoor Climate, (WWAI’08)
Published by WSEAS Press, ISBN:978-960-474-017-8, Corfu, Greece, October 26-28, 2008, pp.
262-265.
9. Alison M. Bowman, W. Smith and J. Brockwell, Soil Biology and Biochemistry, 36, 8, 1253-1260, 2004.
10. L. Talgre1, E. Lauringson1, H. Roostalu, A. Astover, Agronomy Research, 7(1), 125-132, 2009.

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3.P3.
RHENIUM RECOVERY FROM GAS-PURIFICATION WASTES OF THE
KOLA MINING COMPANY
A.G. Kasikov, A.M. Petrova, N.S. Areshina, A.A. Blokhin, E.E. Maltseva
Institution of Russian Academy of Sciences – I.V.Tananaev Institute of Chemistry and Technology of Rare Elements
and Mineral Raw Materials of the Kola Science Centre of RAS(Akademgorodok, 26а, Apatity, Murmansk reg., Russian Federation)

Keywords: rhenium recovery, gas-purification wastes, solvent extraction, ion exchange
sorption
Abstract
Several variants of hydrometallurgical processing of gas-purification wastes resulting from acopper-nickel process, whereby rhenium is extracted and purified, are proposed. For dust- and gas
purification solutions, a complex solvent technology based on rhenium, osmium and H2SO4 solvent
extraction by tertiary amines has been developed. From gas-purification fine dust, rhenium can beextracted by aqueous leaching, whereupon it is isolated from solution by using solvent extraction orion-exchange sorption.
Introduction
As the result of pyrometallurgical digesting of sulphide copper-nickel minerals of the Kola MMC
JSC (Murmansk region, Russia) vast volumes of sulphur dioxide enriched in some volatilecompounds, including Re2O7 are turned out. When the gas is purified, rhenium mostly concentrates
in solutions of the wet gas purification system (GPS) and, partly, in fine dust of the GPS electricprecipitators. At Severonikel JSC (Kola MMC), the rhenium content in wet GPS solutions achieves
8-15 g/L. In view of sizable volumes (~10000 m3 per year), these wastes can be regarded as aconsiderable source of rhenium. The fine dust captured by electric filters in the GPS may contain asmuch as 30-40 g/t Re, which is also attractive for commercial extraction. Nowadays, however,rhenium is not extracted from these wastes being lost during their utilization.
Experimental
In this work, we used industrial specimens of the GPS system at Severonikel Plant (Kola MMC JSC) –washing sulphuric acid solutions containing, g\L: 300-500 H2SO4, 1-5 Ni, 1-3 Fe, 1-5 Cu, 0.05-0.2
Zn, 0.003-0.01 Os, 0.002-0.015 Re; acidic discharge of flue ducts (“flue sludges”), containing, g/L:
1300-1700 H2SO4, 0.5-1.0 Se, 0.015-0.02 Os, 0.001-0.01 Re; and also fine converter dust of the
GPS of the Pechenganikel Plant (Kola MMC JSC). By examining the dust phase composition, we
found that fairly high rhenium contents can pass to solution by way of aqueous leaching during 1 h
at the temperature of Т~80ºC (S:L=1:5). The resulting solution contained, g/l: 8.0 Ni, 4.9 Cu, 13.0
As, 13.7 Fe, 6.3 Zn, 0.017 Mo, 0.005 Re, pH=0.8.
Large-scale laboratory testing of rhenium solvent extraction from process solutions was carried out
at a laboratory cascade of mixer-settler extractors designed and made at ICTREMRM KSC RAS.
As a reagent, TiOA solutions of Hostarex A324 brand admixed with “pure”-grade 2-octanol were
employed.
The sorption experiments proceeded under dynamic conditions in a glass column filled with aweakly basic macroporous anionite Purolite of A170 brand, in which the ratio of the anionite layerheight to the column inner diameter was 10:1.

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140
120

1

100

С(Re)org., mg/l

Results and Discussion
For rhenium extraction from wet GPS solutions, wedeveloped a complex technology providing for
H2SO4, Re and Os extraction. Since solvent
extraction of solutions containing >850 g/L H2SO4,
is of little effect, it was proposed to undertake
rhenium extraction from the strongly acidic flue
sludges after they are diluted with washing acid, sothat the GPS solutions were processed
simultaneously. The extragents in this case were
30% TiOA in 2-octanol and pure 2-octanol. As canbe seen from Fig.1, the mixture with tertiary amines
is more effective.

80

2

60
40
20
0

Moreover, the 30% TiOA and 2-octanol mixture
0
0,5
1
1,5
2
2,5
effectively extracts H2SO4 from gas-purification
С(Re)aq., mg/l
solutions, which is obtained after aqueous reextraction. Rhenium and osmium accumulate in the Fig. 1. Isotherm of rhenium(VII) extraction fromwet gas purification system solution
circulating organic phase. The rare metal-rich
1 – 30% TiOA+70% 2-octanol;
extragent should be regularly subjected to deep re2 – 2-octanol;
extraction with alkalis. After osmium separation
and additional extractive concentration, a marketable ammonium perrhenate can be obtained. A
schematic diagram of the complex extraction technology for wet GPS solutions, yielding rhenium,
is presented in Fig. 2.
Scrubbing

Acidic flue
sludgessulphuric acid
Mixingand settling
Filtration
TiOA+
octanol-2
O:A=(3-5):1

H2O

Rough Se-Os
concentrate

SX of

Cutoff of

H2SO4, Re, Os

Recycled
extragent

H2SO4 stripping

NaOH

Re-Os strippingTechnical-gradesulphuric acid

H2SO4

Neutralization

Re-Os pregnant
extragent

O:A=(3-5):1

Oxidant

TiOA+
octanol-2
O:A=1:(10-20)
NH4OH

Os distillation

SX of
Re
Re stripping

KOH
Oxidant
C2H5OH

Evaporation
SX of andprecipitation
Re stripingRe
Ammonium
perrhenate

Os catching
Os distilation
Precipitation
Os catching
Potassium
Ososmatecatching

Precipitation

Fig. 2 Comprehensive Solvent Extraction technology of the wet gas purification system wastes of“Severonikel” Plant of Kola MMC JSC.
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During the large-scale laboratory testing of the new technology, the scrubbing sulphuric acid fromSeveronikel Plant was processed at a extractor cascade as the result of which ~70% H2SO4 andabout 80% Re and 60-70% Os were recovered.
For extracting and concentrating of rhenium from leaching solutions of GPS fine dust, solvent
extraction and ion-exchange technologies were applied. The schematic flow-sheet is shown in
Fig.3.
Due to very low rhenium concentrations in dust leaching solutions, we have tried pre-concentrating
rhenium by using a highly selective Purolite ionite of the А170 brand. 15 L of solution were
processed to obtain a desorbat containing 0.2 g/L rhenium and 0.016 g/L molybdenum. The level of
Re sorbed out was comparable with that after solvent extraction, but the process selectivity was
higher. For practical realization, we recommend the flow-sheet presented in Fig.3, providing a very
high Re concentration and removal of most of impurities. Pre-concentration in this case can be done
through either solvent extraction or sorption.
Fine dust
H2O
Leaching
ТiOA+

Purolite А170

octanol-2
Raffinate

Raffinate
Sorptionto processing
H2O

Rhenium SX
to processing

Wash solution
Washing

Washing

H2O
ТАА

А170
Desorption

NaOH

Stripping

H2SO4

рН-correction
ТiOA+
Rhenium SX
octanol-2
Stripping

NH4OH

Evaporation andprecipitation
Ammonium
perrhenate
Precipitation

Fig. 3 Hydrometallurgical technology of rhenium recovery from fine dust of the gas purification
system of “Pechenganikel” Plant of Kola MMC JSC.
Conclusion
The aim of this work was to find methods for rhenium extraction from wastes of dust-and-gas
purification systems at copper-nickel smelters. As the result, several variants of hydrometallurgicalprocessing have been proposed.

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3.P4.
SOLVENT EXTRACTION OF RHENIUM(VII) FROM ACID SOLUTIONSWITH HIGH-MOLECULAR ALIPHATIC ALCOHOLS
A.G. Kasikov, A.M. Petrova
An Institution of the Russian Academy of Sciences - I. V. Tananaev Institute of Chemistry and Technology of Rare
Elements and Mineral Raw Materials of Kola Science Centre of RAS (Akademgorodok 26a, Apatity, Murmansk reg.,
Russian Federation)

Keywords: rhenium, solvent extraction, high-molecular alcohols, acid solutions
Abstract:
Rhenium(VII) extraction by high-molecular aliphatic alcohols С8-С12 from HCl and H2SO4
solutions, including the effect of alcohol structure and aqueous phase acidity on rhenium(VII)distribution coefficient, have been investigated. As efficient extracting agents, secondary aliphatic
alcohols С8-С12 are proposed. A new solvent-extraction method for extracting rhenium(VII) from
acidic solutions by using secondary aliphatic alcohols has been developed and pilot-scale tested.
Introduction
High-molecular aliphatic alcohols have been widely used for solvent extraction of metals from
acidic solutions [1]. Regarding their physicochemical properties, aliphatic alcohols containing 7–10
carbon atoms in the hydrocarbon chain satisfy the major requirements posed on commercial
extractants (poor solubility in aqueous phase, high flash point, low density, and low viscosity,
providing both a fast phase segregation and chemical stability). In terms of extracting ability torhenium(VII), alcohols rank below amines and organophosphorus compounds, but exhibit betterselectivity, at the same time being less expensive. Furthermore, with such alcohols, there is no need
to use any diluents and modifiers, which simplifies extraction systems.
In this work, rhenium(VII) extraction by С8-С12 alcohols from acidic sulphate and chloride
solutions has been investigated.
Experimental
In this work, we used the following higher aliphatic alcohols produced in Russia: 1-heptanol, 2heptanol, 4-heptanol, 1-octanol, 2-DL-octanol, 1-nonamol, 1-decanol, 4-decanol, 2-dodecanol of the“pure” brand, as well as the imported undiluted 3-octanol of the 97.8% “for synthesis” brand. The
extragents were saturated with the respective mineral acid to preclude its extraction in the process ofrhenium(VII) extraction. The acidic rhenium(VII) model solutions were prepared by diluting the initial
NH4ReO4 solution prepared from a salt of the “pure” brand together with certain amounts of a highpurity mineral acid.
Extraction was performed in 0.05 L in size, plugged calibrated cylinders which were agitated manuallyat room temperature (Т=201ºС). The phase ratio during the extraction was A/O=1 and the contact
time was 5 min, which allowed to achieve equilibrium.
The rhenium(VII) content in the aqueous phase was determined by the color intensity of the Re(IV)thioureal complex forming in the presence of reducing SnCl2 by measuring the light absorption at
λ=390 nm [2]. The rhenium(VII) concentration in the organic phase was calculated by thedifference between the contents in the aqueous phase before and after extraction. Mineral acidconcentrations in solutions were determined by titrimetrically.
Results and Discussion
It has been established that, notwithstanding the satisfactory performance of С10-С12 alcohols during
the rhenium(VII) extraction from acidic solutions, the increasing hydrocarbon radical length tends
to promote etherification with mineral acid, creating compounds with surfactant properties in the
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organic phase. This hinders separating of the phases in the aqueous-organic systems, especially at
the alkali stripping stage. Therefore alcohols like 1-decanol and 2-dodecanol can hardly be
acceptable as extractants from acidic solutions. The extracting ability of C7-C9 alcohols with regard
to rhenium(VII) is shown in Fig. 1.
2,5

lgDRe

2,5

Heptanols

lgDRe
2,5

Octanols

lgDRe

●1

Nonanols

2

2

2

○2

1,5

1,5

1,5

▲3

1

1

1

0,5

0,5

0,5

0

0

0

-0,5

-0,5

-0,5

-1

-1

-1

0

1

2

3

4

5

6

7

8

0

1

2

3

4

5

6

7

8

∆4
■5
□6

0

1

2

3

4

5

6

7

8

С(HX), mole/L
Cinit.(Re)=10-3 mole/l, O/W=1/1, extraction from HCl (1, 3, 5) and H2SO4 (2, 4, 6).
Heptanols: 1-heptanol (1, 2), 2-heptanol (3, 4), and 4-heptanol (5, 6);Octanols: 1-octanol (1, 2), 2-octanol (3, 4), and 3-octanol (5, 6);
Nonanols: 1-nonanol (1, 2), 2-nonanol (3, 4), 4-nonanol (5, 6).
Fig. 1. Rhenium(VII) distribution coefficient DRe vs. mineral acid concentration in the aqueous phase C(HX)
during the extraction from HCl and H2SO4 solutions with aliphatic alcohols C7–C9.

For all these alcohols, rhenium distribution coefficients DRe are greatly dependent on the mineralacid concentration in the aqueous phase with an extraction maximum at approximately 4-7 mole/L,
depending on the alcohol type. Initially, DRe increases with increasing solution acidity due to thepresence of H+ participating in extraction according to the hydrate-solvate mechanism:
ReO4− + Η3Ο+ + nΗ2O + qROH ↔ [Η3Ο(Η2O)n(ROH)q]+ReO4It is evident that, due to increasing H+ concentration, the equilibrium shifts to the right.
The DRe diminishes in the more acidic region in response to the competing process of mineral acidextraction by alcohol.
On transition from primary to secondary alcohols, their extractive ability regarding rhenium(VII)enhances. This must be caused by the fact that the basicity of secondary alcohols is higher than thatof primary alcohols due to intensifying +I inductive effect exerted by the alkyl substituent whenchanging from primary to secondary alcohols having the OH-groups in positions 2, 3, and 4.
Simultaneously, this dependence on the alcohol structure was observed when extracting singlecharged complex anions from sulphate and chloride solutions; at the same time, the double-charged
anion complexes were better extracted by primary alcohols.
For instance, during the extraction of double-charged MoO2(SO4)22- и PtCl62- anion complexes from
acidic solutions using octyl alcohol isomers an inverse relationship between the DMo and DPt
distribution coefficients and the alcohol structure was observed (Fig.2):

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DMo

DPt
1
1
2

2
3

3

C(H2SO4), mole/lC(HCl), mole/lCinit.(Me)=10-3 mole/l, O/W=1/1
1-octanol (1), 2-octanol (2), and 3-octanol (3);Fig. 2. The effect of octyl alcohol structure on molybdenum(VI) and platinum(VI) distribution
coefficient DMo and Re/Mo separation coefficient KRe/Mo=DRe/DMo in solvent extraction fromsulphuric acid media.
Apparently, these dependencies are the result of steric complications emerging when multiply
charged complexes are extracted by secondary alcohols. The dissimilar ability of primary andsecondary alcohols to extract differently charged metal complexes can be harnessed to separate
rhenium(VII) from platinum(VI) and molybdenum(VI) while processing secondary rheniumcontaining raw materials.
Conclusion
Our research findings were used to develop a new extraction method for selective recovery ofrhenium(VII) with secondary aliphatic alcohols as extractants, which is covered by an RF patent[3].
References
7. Z. I. Nikolotova, N. A. Kartashova, Handbook of Solvent Extraction. Solvent Extraction withneutral organic compounds (Rus), Atomizdat: Moscow (1976) vol. I.
8. L. V. Borisova, A. N. Ermakov, Analytical chemistry of rhenium (Rus), Nauka: Moscow(1974).
1.
RF Patent 2330900, MPK S22V 61/00, S22V 3/26. A method for rhenium (VII) extraction
from an acid solution / A.G.Kasikov, A.M.Petrova (RF) – №2006142845/02; Appl. 04.12.06; Publ.
10.08.08. Bull. № 22.

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3.P5.
PRODUCTION OF THE HIGH PURITY NH4REO4 USINGELECTRODIALYSIS METHOD
A.A. Palant, O.M. Levchuk, A.M. Levin, O.V. Reshetova
IMET RAS, Moscow, reshetovaolga@list.ru

At the last years in Europe it was passed new high standards to the NH4ReO4 quality.
Our long-termed experience shows that standard method of recrystallization doesn’t produce
NH4ReO4 of high quality. The objective of this work was the investigation of the ability of the ultra
pure NH4ReO4 producing. For this problem solution the process flowsheet was used: NH4ReO4 –electrodialysis synthesis – NH4ReO4 by ammonia precipitation.
In this paper NH4ReO4, which contains next impurities, %: Na, Mg, Mn, Al, Ni, S – 0.002,
Mo – 0.01, Cu, Fe – 0.01, was studied. The investigations were carried out in the three-cellelectrodialysis apparatus, which have included two membranes: the first was MA-41IL and thesecond was MK-40. At the first time it was added 5 g/l of the HNO3 to the anodic cell, wherebidistilled water was, and 100 g/l of the HNO3 to the cathodic cell. NH4ReO4 was periodically
added to the middle cell. It was producing the pregnant solution of the HReO4 with CRe=400 g/l as aresult of electrodialysis. From this solution NH4ReO4 was precipitated by NH4OH using standard
method.
The process conditions were: I=2.5-5.0 A, U=18-25 V, temperature in the anodic cell was 2030°C, in the middle cell 25-40°C.
NH4ReO4 crystals contain next impurities, %: Fe – 0.00008 (0.0005), Al – 0.0001(0.0001),
Cu – 0.00005 (0.0001), Mo – 0.00005 (0.0005), Ni – 0.00005 (0.0001), Mn – 0.00005 (0.0001), Mg– 0.00005 (0.0001), Ca – 0.00016 (0.0005), Na – 0.00006 (0.0005), K – 0.00004 (0.0005), Cr –0.00005 (0.0001) (in parentheses it are maximum permissible concentration of the impurities inaccordance with new European regulations).

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3.P6.
REGULARITIES OF RHENIUM SALTS OXIDIZING LEACHING
R. Dj. Allabergenov, H. T. Sharipov, R.H. Sharipov, A. A. Niyazmatov
SE «The Central laboratory» under The State Committee of the Republic of Uzbekistan on Geology and Mineral
Resources - The Tashkent institute of chemical technology

Keywords: renium heptasulfide, oxidation, hydrogen peroxide, sodium nitrite oxidationreduction potentiall
Abstract:

In the article are presented mechanism and results of kinetic researches of rhenium oxidizing
leaching from sulfide raw materials. The main processing factors, allowing to provide maximalrhenium extraction are determined.
Introduction

The basic forms of rare metals composing a sulphide concentrate, extracted from the molybdenum
production solutions, are rhenium heptasulfide and molybdenum and tungsten trisulfides. The
heptasulfide form of rhenium (Re2S7) constituent concentrate –– black substance, almost insoluble
in water, hydrochloric acid, 50 % sulfuric acid; dissoluble in hydrogen peroxide, nitric acid, mixtureof caustic soda or ammonia water with hydrogen peroxide. The Re2S7 disoxidates to metal during
red-heating in hydrogen flow, and when heating in air it ignites generating Re2O7 and SO2 [1-3].
It is the first experience of technological estimation of rhenium sulphide concentrate oxidative
catalytic leaching in sulfuric medium in the presence of sodium nitrite and oxygen in conditions of
rarefication.
In this connection, and considering that it is necessary to utilize rhenium heptasulfide, resulting inprocess of the molybdenum production tails utilization, and study of regularities of this leaching
form is actual. There are scientific novelty and practical use perspectives. Investigations wereconducted by means of the rhenium sulphide concentrate leaching method in a way of disperse
phases dissolution. This way is the closest to real technological conditions and allows to receivenecessary data on optimum parameters of process, suitable for industrial scaling, immediately
during experiments.
Experimental
The analysis of rhenium concentration was carried out by ICP/MS «Agilent-700» and atomicabsorption spectrophotometer «Zeenit-700», the redox potential in solutions was measured by
Ionmeter-74.
Results and Discussion.
According to the data presented in literature and results of investigations, leaching in acid solutionsin oxidizing conditions in the presence of sodium nitrite and oxygen allows to obtain maximal
decomposition of various thrust raw materials. By way of examples of various raw materials
leaching (table № 1) with maximal decomposition of the basic component is shown, that for
breakage of the strongest type of bond - covalent bond - increased oxidation-reduction potential of
media (above 740 millivolt) is required, and for breakage of ionic bond - the main bonding power inminerals and sediments - oxidation-reduction potential of media can be more lower than 720
millivolt.
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Table 1. Optimum experimental values of oxidation-reduction potential for realhydrochemical systems (The technological mode of experiments is resulted on fig. №1)№

Raw material

1

Nickel matte

2

Cement cooper

3
4

Molybdenic
end productRhenium
concentrate

Experimentaloxidationreduction potentialof raw material
full decomposition,
millivolt bychlorine-silver
electrode

The basic
mineral of
raw material

Bond typein baseminerals of
raw material

Alloy of Ni,
NiS, CuSCuO +Zn(OH)2

Basically
covalent
Basically
covalent

MoS2

ionic bondRe2S7ionic bondAmorphous black powder

700-720

Crystal structure

Lump fritted material
Metallized material in theform of a powder
Hexagonal layer structure,
trigonal prisms

780-800
740-760
720-740

5

Cooperconcentrate

CuFeS2ionic bond

In structure tetrahedrons[CuIS4],[FeIIIS4],[SCu2Fe2]

690-7106

Sulfurconcentrate

FeS2

ionic bondType of lattice - cubic

605-625

7

Vanadiumcatalysts

NaVO3,KVO3,
VOSO4

ionic bond

Crystal salts

490-520

Ni(OH)2

ionic bondAmorphous sediment490-510

CuSO4 CuS

ionic bond

Crystal salts

385-400

8
9Nickelaccumulators
Fine powder ofcopper smeltery

This makes it possible to draw a conclusion that different minerals decomposition is actually
defined by uniform parameter - oxidation-reduction potential of leaching solution. Simplicity of theprocess parameters control and possibility to predict its results are advantages of the revealed
regularity which proves, that oxidation-reduction potential is the effective characteristic allowing tominimize search of an optimal technological mode of leaching. For this purpose it is recommended
to model system «acid-water-oxygen-sodium nitrite», used as leaching media which should provide
oxidation-reduction potential in the presence of one or another raw material in specified interval,that guarantee high parameters of process acidic oxidative catalytic leaching.
It is necessary to maintain pulps oxidation-reduction potential on a defined level depending on
mineralogical and chemical composition of raw material. Control of oxidation-reduction potential
should be implement according to consumption of reagents, providing necessary hydrodynamic
regime in a non-standard leaching reactor with deep gasmain for oxygen and simultaneous contactof solid, liquid, steam and gas phases by means of the original mechanism of agitation. Observanceof the specified requirements provides realization of oxidation-reduction processes in a working
space of the reactor, excluding any emissions to surrounding environment. This data are ofscientific and practical interest for recycling and processing of various thrust mineral raw materials.
Behaviour of rhenium in these conditions can be described by the following chemical model. Thismodel demonstrates reactions of formation super rhenium H4Re2O9 and rhenium HReO4 of acids insolution:
2Re7+ + 4,5 O2*- + 4Н+ = H4Re2O9 + 9е- ;Re2S7 +NO+ +2H+ -6e- + 4,5O2-* = 2НReO4 +NO2 + 7 S;
Re2S7 + H2NO2+ + 4O2*- 7е- = 2HReO4 + NO2 + 7 S;
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Re2S7 + 2H3O+ + 4O2*- = 2HReO4 + 7S + 2 Н2О 6е- .
The active beginning and the motive forceof these processes are radicals: nitrosonium(NO + or H2NO2 +), superoxide oxygen (O2*) and oxonium ion (H3O+). These radicals
are generated in a working space of aleaching reactor and serve for rhenium
extraction in to solution through themechanism of oxidation-reduction. The
oxidation-reduction mechanism consists in aprocess when sulphur is oxidising to atomic
S2 - - 2e - = S, nitrosonium ion is reducting
to nitrogen oxide NO + + 1 e - = NO, andnitrogen oxide is oxidising to dioxide
NO + l О2*-+ 1e - = NO2 which in aqueous
medium forms nitrogenous acid - a sourceof active radicals. In formation of 4
molecules of nitrogenous acid in a liquid
phase participate 5 moles of gas(4NO+O2+2H2O = 4НNO2). Consequently
the absolute pressure of a gas phase over asolution declines. This provides rarefication
in a reactor. As reaction of nitrogenous acidregeneration is irreversible its rate grows
with fall of absolute pressure, andconsequently, rate of oxygen consumption
Fig. 1. Influence of oxidation-reduction potential
with formation of active radicals grows.
of sulfuric solution (200 g/l H2SO4) in the presence ofCharacteristic feature of oxidative
NaNO2 (0,7 g/l) and oxygen (partial pressure 80 pascal-3
catalytic
leaching is combination of two
or 0,8 0*10 atm.) on rate of metals extraction fromО
processes in one reactor: regeneration ofdifferent raw materials; temperature 75-80 С; S:L
activeoxidizers-radicals
and
their
=1:4-5; duration of mixing - 60 minutes; number ofsimultaneous
consumption.
In
otherwords,
revolutions - 600 per minute ; рН-1,5; rarefication -10there is a multiple regeneration of nitrogen
60 millimeter of water (below atmospheric).
oxides directly in a working space of areactor at the expense of oxygen. As a result allocation of a gas phase outside the reactor is ruledout and full consumption of oxygen and oxidizers-radicals is provided.
Studying of kinetic mechanisms of rhenium sulfide oxidative leaching indicated, that formation ofrhenium and super rhenium acids in sulfuric solution is possible in wide range of oxidationreduction potential and рН values of leaching media. Oxidation-reduction potential is conditioned
by acidity of media, presence of oxygen and sodium nitrite: perceptible oxidation starts at рН-1 andlower, then initiates oxygen consumption, regeneration of nitrogenous acid and growth of metal
extraction in to solution. It confirms data about participation of hydroxonium in reactions of active
radicals formation in acidic medium which is not enough in the subacidic media.
For maintenance of the maximum regeneration of nitrogenous acid initial acidity should be
not lower 100 g/l of sulfuric acid; by рН 0-1 in solutions with oxidation-reduction potential above
600 millivolt decomposition of rhenium heptasulfide occurs without kinetic difficulties; Low initial
acidity of sulfuric solution (рН 2-3) not allows to exceed amount of nitrogenous acid regeneration
more than 20 % from the initial content; the reason is weak interaction of sodium nitrite and thesubacidic media. In this conditions rhenium practically is not oxidised, nitrogen oxide from solution
it is not allocated, oxygen is not consumed; in the area of low acidity (рН 3-4) and low
concentration of nitrite-ion (0,6-0,7 g/l) raw material oxidation is not observed at all; meanwhile
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011rate of rhenium leaching linearly increases proportionally to agitating intensity increase. A
condition of effective oxidation-decomposition with high rate of nitrogenous acid regeneration isintensive agitation of a pulp by means of a mixer with number of revolutions 600-800per minutewith maintenance rarefication in a reactor-10-50 millimeters of water; The further increase ofrevolutions causes decelerating of process rate that apparently is attributed to transient condition ofregeneration process.
Dependence of rhenium dissolution rate and nitrite concentration is complicated: up to
concentration=0,7 g/l rate of leaching increases; from 0,7 to 2,8 g/l of sodium nitrite - a transientcondition; more than 3,5 - g/l rate of rhenium leaching is stabilised.
Rate of rhenium leaching in conditions of initial increasing acidity of media in the range of 5-50 g/lof sulfuric acid increases linearly and a proportionally; when acidity exceeds 50 g/l process rate
decreases approximately in the same dependence.
In conditions of oxygen lack in system rate of acid regeneration reaction decreases and rareficationin reactor reduces to values less than 10 millimeters of water rarefication degree depends on two
factors: amount of nitrogen oxides in a gas phase and rate of oxygen feed in to a reactor. Nitrogenoxides are the catalyst of the oxidising process which function consists in assimilation, i.e. ofoxygen solubility increasing.
With temperature growth in an interval 25-100ОС and moderate decrease of leaching rate isobserved; when acidity and temperature of media increasing the rate of leaching increases.
However, by acidity is more than 100 g/l of sulfuric acid and temperature is more than 120ОСleaching process inhibition is observed, probably to result from accludation of elemental sulfur
creating diffusive impediments for rhenium leaching and process turns in to intradiffusive area,
where rhenium leaching rate characterizes by the rate nitrosonium radical diffusion through a layerof elementary sulphur.
At temperature 60ОС and initial concentration of sulfuric acid 250 g/l and sodium nitrite
concentration 0,7 g/l rhenium leaching proceeds in a kinetic mode without any diffusion difficulties.
Oxidation-reduction potential makes 620-630 millivolt [by chlorine-silver electrode]. All otherthings being equal, but at concentration of sodium nitrite - 2,8 g/l, oxidation-reduction potential of
media increases to 700 millivolt, and rhenium leaching rate decreases, that testifies to transition ofleaching process in to intra-diffusion area.
Provision of active hydrodynamic regime of leaching is the indispensable condition fortechnological efficiency of oxidising catalytic leaching of sulphide raw materials. This regime
provides maximal contact of all phases of media: «raw material – water – acid - sodium nitrite oxygen». To this effect are recommended special devices with ejection-circulating agitation ormechanical high-speed agitator with diffuser.
Conclusions.
Thus, rhenium sulphide concentrate oxidative catalytic leaching in acidic medium in the presence ofoxygen and catalyst sodium nitrite in conditions of rarefication allows to attain maximal rhenium
extraction in to solution - 98-99 %. Extraction completeness is provided with amount of oxidisingpotential of solution which is supported by low concentration of sodium nitrite in the presence ofoxygen and by oxidative regime of leaching. The process regime is regulated by technologicalparameters: acidity, temperature, concentration of sodium nitrite and oxygen and agitation intensity.
References:

1. R.D. Allabergenov, R. K. Akhmedov, H. S. Sabirov, C. V. Mikhailov, H. R. Sharipov. Mainsources of raw materials and ways of rhenium extraction. Geology and Mineral Resources 2010
№ 5 p.43-48
2. A.A. Polant, I.D. Troshkina, A.M. Chekmaroev. Rhenium Metallurgy. Moscow. 2009, 187.
3. G.I. Abashin. Recovery of rhenium from waste non-ferrous alloys, 1960 № 5 p.69-70.
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E. Johnstone, A. Nadykto, Ya. Obruchnikova, B. Bryskin, N. Kravchenko, E. Nazarov

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3.P7.
RHENIUM SORPTION FROM URANIUM-CONTAINING SOLUTION BY
NANOSTRUCTURED IONITES
I.D. Troshkina, A.V. Shilyaev, N.V. Balanovskiy *, А.М. Chekmarev, О.А. Chernyadyeva
D. Mendeleyev University of Chemical Technology of Russia,
Miusskaya Sq. 9, Moscow 125047, Russian Federation. E-mail: tid@rctu.ru
Federal State Unitary Enterprice Leader Research Institute of Chemical Technology,
33, Kashirskoye shosse, Moscow 115409, Russian Federation.
E-mail: tid@rctu.ru

Keywords: rhenium, sorption, acid solution, nanostructured ionites.
Abstract.
Rhenium is traditionally obtained as by-product in the processing of molybdenite and copperores concentrates. Limited resources of traditional raw materials in Russia are responsible for the
searching of new sources of rhenium. Uranium–containing polymetallic raw material is additionalsource of rhenium [1]. Rhenium was recovered from uranium ores in USA from 1969 to 1974
(Texas, Susquehanna Corporation).
Effective method of uranium ores processing is the underground leaching. Productive
solutions of uranium contain 0.1-0.5 mg/l Re. Rhenium as by-product is recovered by sorption.
The aim of this study is the rhenium recovery in processing of model productive solution ofunderground leaching of uranium. The sorption of rhenium by nanostructured ionites was used inthis paper. The model solution contained: sulfate-ion – 10 g/l; chloride-ion – 1 g/l; rhenium(perrhenate-ion) – 20 mg/l.
Sorption characteristic are investigated in static and dynamic conditions. The equilibrium,
kinetic and dynamic data are obtained.
Nanostructured ionites are recommended for rhenium recovery from of productive uraniumcontaining sulfuric acid solution obtained in processing of ores by underground leaching.
Introduction
Uranium-containing ores as an additional source of rhenium is known till 1950th whenrhenium was obtained from molybdenum-uranium ores in amount about 1000 kilos in the USA [2].
In CIS area stratified infiltrative exogenous deposits exploited by underground leaching method aresituated in world’s biggest uranium province near the Tien Shan region. Rhenium content in ores ofthis province is from 0.02 to 2 g/1000kg [2].
The possibility of rhenium extraction from mineralized sulfuric solutions imitating the content
of underground leaching solutions by new nanostructured styrene-acrylate based ionites wasinvestigated. The synthesis of those ionites was realized in Leader Research Institute of Chemical
Technology by N. Balanovskiy and A. Zorina.
Experimental
On microphoto of ionite’s grain cleavage obtained by electron microscopy one can see 200-400nm sized spheric grains (Fig.1) and 100 nm sized pores between them (Fig.2).

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Fig.1. The surface of styrene-acrylate base nanostructured ionite’s cleavage

Fig.2. The surface of styrene-acrylate base nanostructured ionite’s cleavage with 100 nm porespredominanceRhenium sorption by nanostructured ionites was produced from model solution [3] containing
20 mg/l of rhenium, 10 g/l of sulfate-ion, 1 g/l of chloride-ion (pH 2). The model of solution
concentrations was based on data of underground leaching solution content. Rhenium concentrationin those solutions is higher than one in productive underground leaching solutions. The choice of
this concentrations is conditioned by sensitivity of photocolorimetric analysis method based onformation of colored thiocyanate complexes of rhenium in hydrochloric acid solutions [4].
Results and Discussion.
The results of rhenium sorption by nanostructured ionites from sulfuric solutions are shown in
Table1.
Table 1. Rhenium sorption by nanostructured ionites from sulfuric solutions

Sorption capacity,
IoniteRossion –25
Rossion –25-35
Rossion –25-65
Rossion –62
Rossion –510
Rossion –511
Rossion –610
Rossion –611

mg/g

mmol/g

The degree ofsorption, %

10,8
8,7
12,6
16,6
16,1
14,8
15,5
14,8

0,058
0,047
0,068
0,089
0,087
0,080
0,084
0,079

54,2
43,5
63,0
83,2
80,6
74,1
77,7
73,8

The distribution
coefficient ofrhenium, ml/g
1181
771
1699
4939
4147
2860
3488
2822

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Sorption isotherms were obtained by method of alternating portions at room temperature with
Rossion-62 and Rossion-510 ionites from sulfuric solutions (pH 2) (Fig.3,4). The linear character ofthe isotherms obtained (Fig. 3,4) allows to apply the Henry equation to describe.
Henry’s constants calculated with least square technique have the following meanings(1,48±0,13)·103 ml/g for Rossion-62 ionite with correlation coefficient 0.91 and (1,88±0,13)·103
ml/g for Rossion-510 ionite with correlation coefficient 0.93.
Rhenium sorption dynamic data were performed from solution containing 1.5 mg/l of rhenium
by Rossion-62 ionite in column of 7 mm internal diameter and 7 cm length. The flow rate ofsolution was 1 ml/min. The breakthrough curve is shown on Fig.5.

Fig.3. Sorption isotherm of rhenium by ion exchanger Rossion – 62 from sulfuric acid solutions.

Fig.4. Sorption isotherm of rhenium by ion exchanger Rossion -510 from sulfuric acid solutions.

Fig.5. Breakthrough curve of rhenium sorption by Rossion-62 ionite from sulfuric acid solution.

The calculated dynamic parameters of rhenium sorption are shown in Table 2.

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Table 2. Calculated dynamic parameters of rhenium sorption

Number of specific
Number of specific volumes
volumes toof solution to saturation of the
breakthrough solutionrhenium resinof rhenium
1130

2300

Total dynamic
exchange
capacity on
rhenium, mg/g
6,8

As can be seen from Fig. 5 and Table 2 rhenium breakthrough occurs after passing 1130 column
volume of solution. Complete saturation of the ionite by rhenium occurs by passing through theionite layer 2300 column volumes of the initial solution. The total dynamic capacity was found to
be 6.8 mg/l.
Conclusions.
On the basis of finding equilibrium and dynamic rhenium sorption data from mineralized
sulfuric solutions the applicability of the new nanostructured styrene-acrylate based ionites
Rossion-62 and Rossion-510 for rhenium sorption from uranium ores’s underground leachingsolutions was shown.
References
1. V.Paretsky, A.Besser, E.Gedgagov, Non-ferrous metals. 10: 17-21 (2008).
2. A.A. Palant, I.D. Troshkina, A.M. Chekmarev, Metallurgy of Rhenium, Science: Moscow (2007).
298 p. (rus.)
3. In-Situ Leaching of Ores, Academy of Mining Sciences, Publishing House: Moscow (1998). 446
p. (rus.). P. 203.
4. L.V. Borisova, A.N. Ermakov, Analytical chemistry of rhenium. М.: Chemistry, 1974. 318 p.
(rus.).

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3.P8.
SORPTION OF PALLADIUM FROM THE RHENIUM-CONTAININGSULFURIC ACID SOLUTION
A. A. Abdusalomov1, I. D. Troshkina1, A. M. Chekmarev1, N. P. Ismailov2
1

D. Mendeleev University of Chemical Technology of Russia(9 Miusskaya sq., Moscow 125047, Russian Federation; tid@rctu.ru)
2
Tashkent Chemical-Technological Institute(32 Navoi str., Tashkent 100011, Republic of Uzbekistan; abdusalomov@mail.ru)

KEYWORDS: sorption, palladium, rhenium, sulfuric acid solution, ion exchange resins, recovery.
ABSTRACT
Solutions formed during the preparation of sulfuric acid from metallurgical gases of copperand molybdenum production are the main source of rhenium. The possibility of palladium recovery
from sulfuric acid solutions by commercial sorbents was studied. The distribution coefficient of
palladium sorption is in the range 3.8·101÷4.0·104 cm3/g decreasing in the order: TP 214> D 4384
(Aliquat 336) > TP 207 > AN-105 > CS-PTFE > A170 > MN 202 (TAA) > MP 62 > VP-14KR.
Ammonia (8%) and/or hydrochloric acid (4 mol/l) were used to eluation of Pd(II) from all of thesorbents examined. Based on data of sorption and eluation for the effective associated recovery of
palladium from rhenium containing sulfuric acid solutions sorbents Lewatit MonoPlus TP 207(Lanxess) and Purolite D 4384 can be recommended.

INTRODUCTION
Rhenium is traditionally obtained as by-product in the processing of molybdenite and copperores concentrates [1].
Rhenium raw materials of Uzbekistan have high complexity with known in recent years asignificant share of the platinum metals. The source of the associated recovery of rhenium andplatinum group metals is copper-molybdenum deposit of Almalyk’s ore field. Its special feature is
the presence of radiogenic isotopes of osmium-187 – a product of the decay of rhenium-187, as well
as appreciable amounts of palladium, platinum, iridium, ruthenium, rhodium.
New mineral of Uzbekistan’s ores - telluride palladium and platinum - the Merenskyite (Fig.
1) was defined [2].
In the smelting of copper concentrates from 6.7 up to 13.2 % of each of the platinum group
goes from the gas phase in the dust, caught in a dust chamber and electric filter [3]. Solutions
formed during the preparation of sulfuric acid from metallurgical gases of copper and molybdenum
production are the main source of rhenium. They contain the sulfuric acid (up to 150 grams perliter), chloride- and fluoride-ions, arsenic, lead, iron, copper, bismuth, zinc and rhenium [4].

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Fig. 1: Coalescence of merenskyite (PdTe2) with virgin gold in molybdenum concentrates of AMMC.
Photograph in the electrons reflected and the characteristic X-radiation Pd, Te, Cu, Pt and Au. Increase in
9000x [2].

EXPERIMENTAL
The aim of this paper is to investigate the possibility of sorption and preconcentration of
palladium from rhenium-containing sulfuric acid solutions. As sorbents were used: a low basic
anion exchanger AN-105, ampholyte VP-14KR, ion exchange resins with different basicity of thecompany Purolite (A 170, MN 202 and D 4384), as well as the company Lanxess (Lewatit MP 62,
MonoPlus TP 207 and MonoPlus TP 214), carbon sorbent, modified by polytetrafluoroethylene(CS-PTFE) (Table 1).
Table 1. Characteristic of the sorbents

Sorbent
MP 62
TP 207
TP 214A 170
D 4384 (Aliquat 336)
MN 202 (ТАА)
AN-105
VP-14KRCS-PTFE

Type
Structure
Functional group
Weak base
Macroporous
Tertiary amine
ChelatingMacroporous
Iminodiacetic acid
ChelatingMacroporous
Thiourea
Weak base
Macroporous
Secondary amine
Composition anionite
Impregnate
Quaternary amine
Composition anionite
Impregnate
Tertiary amine
Weak base
Gel
Cyclohexylamine
Ampholyte
Gel
Pyridine and carboxyl
Carbon sorbent, modified by the polytetrafluoroethylene

Sorption of palladium was carried out in batch conditions for 3 days from the solution of thefollowing composition: palladium - 24 mg/l, sulfuric acid - 100 g/l. The phase ratio of the sorbent tothe solution was 1:500. Desorption of palladium was carried out also in batch conditions at a ratioof 1:60 using ammonia (8%) and/or hydrochloric acid (4 mol/l).
RESULTS AND DISCUSSION
The results showed that the distribution coefficient of palladium in the sorption of the material
under study is located within 3.8·101÷4.0·104 cm3/g decreasing in the order: TP 214> D 4384
(Aliquat 336) > TP 207 > AN-105 > CS-PTFE > A170 > MN 202 (TAA) > MP 62 > VP-14KR(Table 2).

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Table 2. Sorption of palladium by different ionites
Concentration of palladium in Capacity on palladium,the solution after the sorption
ЕPd
Sorbent-3
mg/l·10 mmol/l
mg/g·10-3 mmol/g
MP 62
21.5
202.2
1.4
12.7
TP 207
< 0.3
2.8
11.9
112.3
TP 214
0.3
2.8
12.0
112.3
A 170
16.7
157.0
3.8
35.2
D 4384(Aliquat
< 0,3
2.8
11.9
112.3
336)
MN 202
18.6
174.8
2.8
26.3
(ТАА)
AN-105
7.5
70.5
8,3
78.5
VP-14KR
22.5
211.5
0,8
7.9
CS-PTFE
9.1
85.5
7.5
70.9

Distribution
coefficient Kd,
cm3/g
63
39830
39833
224

Degree of thesorption, %
11.2
98.8
98.8
30.9

39833

98.8

150

23.1

1113
38
829

69.0
7.0
61.9

The best results were observed for the palladium desorption from composition anionite D
4384 (Aliquat 336) by ammonium hydroxide solution (distribution coefficient – 31.7 g/cm3) andfrom ionite TP 207 by hydrochloric acid (distribution coefficient – 38.9 g/cm3) (Table 3,4).
Table 3. Desorption of palladium from different ionites by hydrochloric acid

Ionite

1.4
11.9
12.0
3.8

·10-3
mmol/g
12.7
112.3
112.3
35.2

Residualcapacity on
palladium
·10-3
mg/g
mmol/g
1.1
10.5
3.6
33.6
11.9
111.8
3.5
32.9

Concentration of
palladium in theeluate·10-3mg/l
mmol/l3.9
36.4
139.5 1311.1
<0.1
0.9
4.1
38.9

11.9

112.3

10.2

95.8

29.2

2.8

26.3

1.5

14.2

8.3

78.5

7.1

0.8

7.9

7.5

70.9

Initial capacity
on palladium
mg/g

MP 62
TP 207
TP 214A 170
D 4384(Aliquat336)
MN 202
ТАА
AN-105
VP14KRCSPTFE

Distribution
coefficient Kd,
g/cm3

Degree ofthedesorption,
%

3
39
0
1.1

17.2
70.1
0.05
6.6

274.4

2.8

14.7

21.6

203.0

14

46.3

66.6

21.1

198.3

2.9

15.2

0.8

7.5

0.9

8.2

1.1

6.2

6.9

65.0

10.6

99.6

1.5

8.4

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Table 4. Desorption of palladium from different ionites by ammonia

IoniteInitial capacity
on palladium

Concentration of
palladium in theeluate·10-3mg/l
mmol/l
12.8
120.1
<0.1
0.9
9.9
93.0
7.0
65.8
130.5 1226.5
1.2
10.9
26.6
250.3

Distribution
coefficient Kd,
g/cm3

Degree ofthedesorption,
%

22
0.8
2.1
31.0
0.4
4.0

56.8
4.9
11.2
65.5
2.5
19.2

1.4
11.9
12.0
3.8
11.9
2.8
8.3

·10-3
mmol/g
12.7
112.3
112.3
35.2
112.3
26.3
78.5

0.8

7.9

-

-

33.7

317.2

-

-

7.5

70.9

7.1

67.2

6.7

63.4

0.9

5.3

mg/g
MP 62
TP 207
TP 214A 170
D 4384
MN202
AN-105
VP14KRCSPTFE

Residualcapacity on
palladium
·10-3
mg/g
mmol/g
0.6
5.4
11.9
112.2
11.4
106.8
3.3
31.3
4.1
38.7
2.7
25.6
6.7
63.4

CONCLUSION
Thus, based on data of sorption and eluation for the effective associated recovery of palladiumfrom rhenium containing sulfuric acid solutions sorbents MonoPlus TP 207 and Purolite D 4384
can be used.
REFERENCES
1. A.A. Palant, I.D. Troshkina, A.M. Chekmarev, Metallurgy of Rhenium, Science: Moscow (2007).

298 p. (rus.)
2. S. K. Smirnova, V. V. Kozlov, etc. Mining J. of Uzbekistan, 3: 13-26 (2005).
3. L. M. Rabicheva, V. N. Morozov, et al., Tsvetnye Metally, 12: 54-55 (1981).
4. I. F. Popov, L. I. Mekler, et al. Scientific works of the Central Asia Research Institute of
Nonferrous Metals, 11: 59-98 (1975).

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3.P9.
ULTRAFILTRATION SEPARATION OF RHENIUM AND URANIUMUSING NITROGEN-CONTAINING POLYELECTROLYTES
I. D. Troshkina, T. G. Abdrakhmanov, N. A. Smirnov, A. B. Mayboroda,
K. I. Potapova, A. M. Chekmarev
D. Mendeleyev University of Chemical Technology of Russia,
Miusskaya Sq. 9, Moscow 125047, Russia. E-mail: tid@rctu.ru

KEYWORDS: ultrafiltration separation, uranium, rhenium, polyelectrolyte
ABSTRACTMembrane techniques have been proven for selective recovery and separation of rhenium anduranium from complex multi-component effluents, in particular, the method of complexing
ultrafiltration. The laboratory installation involved standard ultrafilter with semipermeable polymer
membrane (polysulfone fiber). The effects of external factors (ratio of nitrogen-containing
polyelectrolytes Praestol 658, Praestol 859, KF-99 and PGHA to rhenium and uranium, pH value,
concentration of nitrate-ion) on the separation characteristics of the process were studied. The optimal
conditions of polyelectrolytes regeneration were found.
INTRODUCTION
Uranium mines is one of the rhenium sources. Hydrometallurgical treatment of them produces
solutions where rhenium concentration is tenth of mg/l [1,2]. Larges quantities productive solutions
and high market value of rhenium are the base for its reasonable recovery.
Baromembraneous techniques (reversible osmosis, ultrafiltration, microfiltration) widely use forthe separation of solutions. The method of selective concentration combining ultrafiltration withpreliminary complex formation (CF-UF method) is known since 1968 (Michaels A.S., 1968). Highcapacity at low power in combination with high selectivity of the separation allow to use the CF-UF
method for the recovery of valuable or pollutant components from industrial effluents [3,4]. The
ultrafilter used in the CF-UF process passes low-molecular components of solution, but retards highmolecular polyelectrolytes (PE) connecting the ions of constituent. Selective connection is provided
by introducing of functional groups in the PE molecule having high affinity to metal ion. An important
advantage of the CF-UF method for mostly used systems is a high velocity of process, that favourablycompares it with sorption method widely used in the processing of dilute solutions. Method ofcomplexing ultrafiltration was used for rhenium recovery from water solutions [4-6].
The possibility of recovery and separation of rhenium and uranium by the CF-UF method withnitrogen-containing polyelectrolytes Praestol 658, Praestol 859, KF-99 and PGHA was investigated inthis work.
EXPERIMENTAL
In this work following soluble synthetic nitrogen-containing polyelectrolytes Praestol 658 and 859(Degussa, Germany), KF-99 and PGHA (China) were used.
The rhenium concentration in solution was determined by photocolorimetric method [7].
The CF-UF characteristics of rhenium recovery have been studied at the laboratory installation
involved standard ultrafilter with semipermeable polymer membrane (polysulfone fiber with nominal
cut-off molecular mass -40000 amu prepared by phase inversion) [6]. Pore sizes in the dense selective
layer are 10–40 nm. Ultrafiltration module used in this study is a cylindrical device, which is placed
inside the bundle of hollow fibers as set forth in the ends of the shell polymer compound. Ultrafilteron the basis of hollow fibers is a flow-type apparatus, so after the addition of polyelectrolyte to a
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solution containing metal ions, filtration was carried out at the circulation of the solution, maintaining
at the entrance to the membrane module excess pressure 0.5 atm.
Selectivity of the membrane has been studied for uranium and rhenium depending on theconcentration of various polyelectrolytes.
The selectivity of the membrane on metal (φ,%) was determined from the relation:
where SI and Sp - metal concentration in the initial solution and permeate, mg/dm3, respectively.
The separation factor of uranium and rhenium was calculated by analogy with the coefficientof separation of the components of gas or organic compounds.

RESULTS AND DISCUSSION.
The selectivity of the membrane by using polyelectrolyte Praestol 859 reaches 90% at its
concentration of 0,017%, Praestol 658 – from 0,1%, KF-99 – from 0.03%. The selectivity of themembrane in the case of PGHA reaches a plateau, (85% at its concentration of 0.05%).
Minimum concentration of polyelectrolyte in a solution of uranyl sulphate ([U] = 50 mg / dm 3) isdetermined, at which the value of the selectivity reaches 90%, according to this dependence. The
selectivity of the membrane reaches 90% by using polyelectrolyte Praestol 859 at its concentration of
0.017%, while in the case Praestol 658 - from 0,06%.
The effect of nitrate anions and pH value on the process of complexation - ultrafiltration for both
metals was studied at the chosen concentration of polyelectrolytes.
The data obtained shows that the optimal concentration of sodium nitrate for the elution of perrhenate
ions from the polyelectrolyte Praestol 859 is 0.05 mol/dm3; from Praestol 658 - 0.1 mol/dm3; fromKF-99 - 0,03 mol/dm3. In this case, on the one site, a high degree of regeneration (98%) is reached,which provides a wealth of permeate. On the other site, a relatively low concentration of nitrate ions insolution facilitates processing of the permeate by hydrometallurgical methods.
The effect of nitrate ions on the selectivity of the polysulfone membrane on uranium was studied
using polyelectrolyte Praestol 658. Experiments were conducted by joint and separate extraction of
uranium and rhenium from solutions based on the above experimental data on the working pH range
and the influence of the content of nitrate ions on the selectivity of polysulfone membranes onrhenium and uranium. The optimal parameters allowing to selectively concentrate each of thecomponents, or both simultaneously were determined (Table).
Table. The parameters of membrane separation of uranium and rhenium*

Condition

φ Re, % φU, %Separation
factor Re/U-

Separation
factor U/Re
1,2

рН 7,491
92
рН 6,9;192
12,0
0,1 mol/l NO3рН 4,1
96
11
25,8
*
3
initial uranium concentration - 50 mg/dm , initial rhenium concentration - 20 mg/dm3, concentrationof polyelectrolyte Praestol 658 - 0,1 % (mas.)
CONCLUSION
The possibility of recovery and ultrafiltration separation of uranium and rhenium in water solution
using 0.1% solution of polyelectrolyte Praestol 658 was shown. The selectivity of the polysulfone
membrane with selective concentration of uranium is 92% (pH 6.9, the concentration of nitrateions 0.1 mol/l), of rhenium - 96% (pH 4.1).

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REFERENCES
1. A.A. Palant, I.D. Troshkina, A.M. Chekmarev, Metallurgy of Rhenium, Science: Moscow (2007).
298 p. (rus.)
2. In-Situ Leaching of Ores, Academy of Mining Sciences, Publishing House: Moscow (1998). 446 p.
(rus.)
3. G.I.Tokareva, N.I. Tokarev, J.I.Djitnerskij, et al., Selective concentration of metals in solutions
by polymeric connection and ultrafiltration, VIEMS: Moscow (1988), 60 p. (rus.).
4. S.M. Moldabekov, N.V. Kotshergin, A.A. Kamshibaev, U.B.Besterekov. Abstracts of the IV
Conference on the membrane methods of mixture separation, 1987. Moscow, NIITECHIM, 1987, p.
44-45.
5. I.D. Troshkina, A.M. Chekmarev, S.B. Mayboroda, N.S. Smirnov, Abstracts of the Intern.
Symposium on technetium – science and utilization: IST-2005. May 24-27, 2005. Oarai (Japan), 2005,
p. 37.
6. N.S. Smirnov, I.D. Troshkina, A.B. Mayboroda, A.M. Chekmarev, Chemical Technology. 8(10):468-471 (2007)7. L.V. Borisova, A.N. Ermakov, Analytical chemistry of rhenium. М.: Chemistry,
1974. -318 p.

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3.P10.
RECOVERY OF RHENIUM FROM AQUEOUS SOLUTIONSBY FIBROUS MATERIALS
I.D. Troshkina, L.A. Zemskova*, A.M. Chekmarev, A.V. Plevaka,
Aye Minn, A.V. Shilyaev, A.V. Voit*, D. N. Tumanova
D. Mendeleyev University of Chemical Technology of Russia,
Miusskaya Sq. 9, Moscow 125047, Russia. E-mail: tid@rctu.ru*Institute of Chemistry, Far Eastern Branch of Russian Academy of Sciences, 159, pr. 100- letiya Vladivostoka,
690022, Vladivostok, Russia.
E-mail:zemskova@ich.dvo.ru

KEYWORDS: rhenium, sorption, fibrous materials FIBAN, carbon fibers, modified fibers
ABSTRACTThe possibility of rhenium recovery from aqueous solutions by fibrous materials was investigated.
Sorption characteristics of the following fibrous materials: carbon fibers (Busofite and Actylene),carbon fibers modified by electrochemical and chemical method (adsorption on the surface of
natural polyelectrolyte – chitosan) and acrylic fibers FIBAN having the following anion-exchangegroups: -N (CH2COO-)2 (FIBAN А-6) and - =NH, -NH2, -СOOH, ≡N (FIBAN АК-22) have beenstudied. The best capacity parameters for modified carbon materials prepared in the anodic region
and at the open-circuit potential are observed. The half-conversion time τ 0.5 (3-10 min.) for them ismuch less than that for original carbon fibers (τ0.5–60-65 min). The degree of rhenium sorption by
the ionites FIBAN А-6 and AK-22 was equal 70.8 and 97.0 % accordingly. Elution characteristics
for sorbent FIBAN AK-22 are better than for ionite FIBAN А-6.
INTRODUCTION
Granular nitrogen containing anionites and complexing ionites as well as amino containing
impregnates are used for sorption of rhenium. The possibility of rhenium recovery from aqueous
solutions by fibrous materials was investigated. The main advantage of them as compared with
granular ionites is a high sorption rate.
EXPERIMENTAL
Sorption characteristics of the carbon fibers (Busofite and Actylene) modified by electrochemical
and chemical method (adsorption on the surface of natural polyelectrolyte – chitosan) and acrylic
fibers FIBAN (А-6 and АК-22) are studied.
FIBAN-sorbents contain the following anion-exchange groups: -N (CH2COO-)2 (FIBAN А-6);=NH, -NH2, -СOOH, ≡N (FIBAN АК-22). The synthesis of these ionites was described by authors[1].
Chitosan, a natural organic polymer containing amino groups can adsorb ReO4- and sorption
depends on the ionic strength and pH values of its solutions. Specifically, chitosan has primaryamino groups that have pKa values of about 6.3. At pH below pKa most of the amino groups areprotonated making chitosan a water-soluble, cationic polyelectrolyte. At pH above the pKa chitosanamino groups are deprotonated, and this polymer becomes insoluble [2]:SolubleUnsoluble288

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These properties of chitosan were used for obtaining new sorption materials (Table 1).
Carbon clothes with high specific area (~700-800 m2/g) were used as initial material for obtaining
the sorbents. Carbon fibers were modified with chitosan by means of electrochemical process andadsorption on the carbon cloth. Thus, the three types of the sorption materials were obtained by thefollowing ways: by cathodic and anodic polarization (in potentiostatic regime) and at open-circuit
potential in electrolyte solution. The amount of chitosan precipitate depends on the treatment
method at the same concentration.
The determination of the types of nitrogen containing groups was carried out by the X-ray
photoelectron spectra. The X-ray photoelectron N 1s spectra of all the samples were recorded.
Deconvolution of these spectra gives two peaks corresponding to nitrogen of the initial andprotonated amino groups (Fig. 1).
Table 1. Regime of obtaining and characteristics of modified carbon fibers.

Sorbent

Potential, mV

Potential
Specific
immersion, mV* surface, m2/g**
Base – Busofite (BHUM)
BHUM-1-900+60
872
BHUM-2-700+70887
BHUM-3-500+50886
BHUM-4-200+70890
BHUM-5-100+80902
BHUM-6
+100
+50
1015
BHUM-7
+600
+290
1278
BHUM-8
without polarization
+230
1145
Base - Actylene (AHUM)
AHUM-1
-100
+150
716
AHUM-2-500+90628
AHUM-3-900+70593
AHUM-4
+100
+180
749
AHUM-5-900+50615
AHUM-6
without polarization+300
852
AHUM-7
+900
+580
945
AHUM-8
+900
+620
918
AHUM-9
+600
+450
965
AHUM-10
+900
+540
941
AHUM-11
+900
+450
950
AHUM-12
+900
+450
950
* - The potential of immersion is defined in 0.9% NaCl solution.
** - The specific surface area is calculated by measuring of the HUM electrochemical capacity inthe formation of the electrical double layer.
N(E)

N(E)
10000

4000

а)

б)

8000
3000
6000
2000
4000
1000
2000
Eb, eV
0
397

398

399

400

401

402

403

404

Eb, eV
0
397

398

399

400

401

402

403

404

Fig. 1. X-Ray photoelectron N 1s spectra of carbon fibers (Busofite) modified
with chitosan by cathodic (a) and anodic (b) polarization.
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It was determined that chitosan precipitated at the negative electrode had much less amount ofprotonated amino groups.
The surface of the original and the modified fibers was investigated by scanning electron
microscopy (Fig. 2).

a)

c)

b)

d)

Fig. 2. Photos surface of the carbon fibers obtained by e-force microscopy: a) original fiber, and b)
BHUM (anodic polarization, 900 mV), c)BHUM (without polarization), d)BHUM (cathodic polarization,-900 mV).

The surface of the fiber source (the width of the fibers from 3 microns to 10 microns) is smooth andcovered with well-developed network of pores (Fig. 1a). Round and oval pores with diameters close
to the boundary between meso-and macropores, ie, ~ 50-200 nm are visible. During theelectrochemical deposition of chitosan in the anode potential biopolymer film is deposited in theform of particles or hemispherical shape, which is located on the borders of macropores (Fig. 1b).
Chitosan which chemically deposited on the fiber surface exists in various forms: as a film or
spherical particles with a thickness of 500 nm to 2000 nm (Fig. 1c). Probably, by the swelling themolecule of polymer fibers is introduced between the fibrils and filled the space. In the cathodic
modification (Fig. 1d) chitosan film coats the fibers, forming growths of complicated form on thesurface. In places with quiet relief the film has a surface with multiple bulges. On the surface of thefibers macropores from 100 nm to 600 nm are developed. The film thickness on flat ground isapproximately 200-250 nm.
The equilibrium and kinetic characteristics of rhenium sorption by modified fibrous carbon
materials treated electrochemically with recovery potentials varying from – 900 to +600 mV from
aqueous solutions in the presence of natural biopolymer chitosan.
The rhenium sorption by fibrous materials was carried out in batch conditions. The ammonia
solution was used for rhenium elution.

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RESULTS AND DISCUSSION.
Rhenium sorption on fibrous carbon materials and carbon fibers modified by electrochemical andchemical method
Investigation of sorption properties of the HUM materials obtained as regards to perrhenate ion was
carried out. The highest rhenium capacity is observed for the material prepared at the recovery
potential +600 mV (Table 1,2).
Table 2. Rhenium sorption and desorption characteristics of modified carbon fibers BHUM and AHUM.

Sorption
DegreeCapacity Distributionofcoefficient,of Re,
sorption,
3
mg/g
cm /g
%
BHUM-7 18.5
11600
92.3
AHUM-6 19.5
39000
97.5
AHUM-9 19.8
66000
98.8
AHUM-10 19.0
17300
94.8
HUM

Desorption
Distribution
coefficient,
3g/cm

Degree ofdesorption,
%

23700
8900
38000
7200

82.3
78.3
93.9
73.5

Isotherms of rhenium for sorbents BHUM-7 and AHUM-9 have a convex shape. They are describedby the Langmuir equation. The Langmuir constants in the equation were equal (7.3 ± 0.8) ·10-2 l/mg
and (1.9 ± 0.3) l/mg, respectively.
It was found that the modified sorption materials (BHUM-7 and AHUM-9) had higher sorption
capacity as compared to the initial material. The results of this investigation are shown in Fig. 3.

ab

Fig.3.Integral kinetic curves of rhenium sorption from aqueous solution:
1a - Busofite; 2a – BHUM-7; 1b - Actylene; 2b – АHUM-9.

It was established that the kinetic characteristics of the sorbents BHUM-7 and AHUM-9 arecomparable (Fig. 3). Best kinetic properties are observed for the sorbents BHUM-7 and the AHUM6 (no polarization). The half-conversion time τ0.5 is 3.0 min. and 7.5 min. respectively. It was foundthat the rate of rhenium sorption by modified HUM significantly higher than by the original carbon
fiber (for Busofite, for example, τ0.5 is equal 65 min.).
The following model to describe experimental results can be possible [3,4]:- carbon porous materials modified with chitosan in anodic area have a large number ofprotonated amino groups.
- large number of amino groups in protonated form can interact with the negatively charged
perrhenate anion ReO4- via electrostatic interaction as in [3].
Possible types of interaction perrhenate-ion sorption by chitosan-carbon materials are:With carbon fiber materials:- physical adsorption in the pores;- electrostatic adsorption of perrhenate ion, due to the positively charged surface of the
carbon material;
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- ion exchange of perrhenate ion with the surface oxygen anion groups (OH-).
Due to the electrochemical processing:- electrostatic adsorption of perrhenate ion, due to the positively charged surface of carbon
material (anode region).
Through modification of chitosan:- interaction of perrhenate ion with protonated amino groups of chitosan adsorbed from a solutionof carbon material;- interaction of perrhenate ion by protonated amino groups of chitosan deposited on the surface
during the electrochemical process in the cathode region.
Rhenium sorption by FIBAN-ionites. The degree of rhenium sorption was 70.8 and 97.0 % for theionites FIBAN А-6 and AK-22 accordingly (Table 3).
Table 3. Rhenium sorption from sulfuric acid solutions at FIBAN-sorbents*

FIBAN Degree of rhenium
sorption, %Capacity of rhenium,
mg/g

A-6

70.8

1.8

АК-22

97.0

2.4

* ratio of sorbent to solution = 1:50 (g: ml), the Re concentration –50 mg/l, pH 2.
Elution characteristics for sorbent FIBAN AK-22 are better than for ionite FIBAN А-6 (Table 4).
Table 4. Eluation of rhenium from FIBAN-sorbents*

FIBAN

Degree ofDegree ofTotal degree
desorption after desorption after of desorption,
1st contact, %2nd contact, %
%
A-6
56.5
63.4
84.7
АК-22
55.1
93.6
97.1
* ratio of sorbent to solution = 1:20 (g: ml), concentration of ammonia in solution – 8 %.
CONCLUSION.
Rhenium sorption has been studied from aqueous solutions on fibrous materials of two types:
chitosan-modified carbon material (in the cathodic and anodic polarization regions and at the opencircuit potential) and acrylic ionites FIBAN.
- The best capacity parameters for HUM materials prepared in the anodic region and at the opencircuit potential are observed. The sorption behavior of the materials depends on the number ofthe protonated amino groups. The highest rhenium capacity of BHUM-7 was 18.5 mg/g and for
AHUM-9 - 19.8 mg/g (without polarization). The rhenium sorption isotherm has a convex
shape. The calculated Langmuir constants were equal (7.3 ± 0.8) · 10-2 l/mg and (1.9 ± 0.3)
l/mg, respectively.
- Kinetic characteristics of rhenium sorption from aqueous solutions by modified HUM have beenstudied. The half-conversion time τ 0.5 (3 - 10 min.) is much less than that for original carbon
fibers (τ0.5 – 60-65 min).
- The possibility of rhenium sorption by fiber ionites FIBAN was shown. The degree of rhenium
sorption by ionite FIBAN AK-22 (97 %) is more than for ionite AK-6 (70.8 %).
REFERENCES.
1. V. S. Soldatov, G.I. Sergeev, GWChO. 1: 101-106 (1990).
2. Li-Qun Wu, Anand P.Gadre, Hyunmin Yi, et. al., Langmuir,18: 8620-8625 (2002).
3. E. Kim, M.F. Benedetti, J. Boulegue. Water Research. 38: 448-454 (2004).
4. A.V. Plevaka, I.D. Troshkina, L.A. Zemskova, A.V. Voit, J. of Inorg. Chem. 54(7): 1229–
1232 (2009).
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3.P11.
RHENIUM RECYCLING FROM HEAT-RESISTANT RHENIUMCONTAINING NICKEL-BASED SUPERALLOYS
A.G. Kasikov, A.M. Petrova, P.B. Gromov, V.T. Kalinnikov
An Institution of the Russian Academy of Sciences – I.V.Tananaev Institute of Chemistry and Technology of Rare
Elements and Mineral Raw Materials of the Kola Science Centre of RAS(Akademgorodok, 26а, Apatity, Murmansk reg., Russian Federation)

Keywords: rhenium, recycling, heat-resistant nickel alloy, waste
Abstract
Two new flow-sheets of rhenium recycle technology from nickel-based heat-resistant alloys (HRA)
have been investigated. By the first variant, the nickel base of HRA is leached by a mineral acid,with rhenium pre-concentrated in the residue, followed by rhenium high-temperature distillation as
Re2O7. After dissolution and hydrometallurgical purification of sublimate, technical-grade
ammonium perrhenate is obtained. The second variant incorporates waste leaching with acid underoxidizing conditions, transferring more than 95% of rhenium to solution. Rhenium is selectively
recovered by solvent extraction with secondary alcohol. After the extragent washing, a pure
perrhenate ammonium solution and a technical-grade rhenium salt are produced. The proposed
schemes have been tested on an enlarged laboratory scale.
Introduction
It is known that heat-resistant alloys (HRA) of the latest generations contain 4-9% rhenium, so boththeir treatment and operation wastes can be regarded as fairly rich rhenium sources. Although theamount of such wastes, annually turned out in Russia, is ~25-35 t (according to FSUE “VIAM”
data), only a small part of them is currently recycled.
Rhenium recycling has recently become a burning issue. This is due to many factors, the principal
one being runaway prices resulting from disbalance of supply-demand at the rhenium market.
Peaking at 2008 (USD 10560 $\kg), the Re prices remain fairly stable (6600 $/kg) [1],notwithstanding the ongoing economic crisis.
However, according to A. Lipmann, an authority in the “minor-metal” issues, the industrial
application of the methods for HRA processing is limited due to their high cost (1 kg of secondaryrhenium costs ~3000 USD\kg) and low effectiveness (the yield is ~70%) [2]. Hence the necessity todevelop effectual technologies of rhenium recovery from HRA.
Results and Discussion
Since HRA are multicomponent, the metals from them are conventionally extracted byhydrometallurgical methods [3]. One of the problems arising here is crushing of extremely hardlarge HRA lumps (such as turbine blades and other elements weighing up to several kg). Based on
our experience of hard nickel alloys processing [3], we proposed that lumpy HRA wastes of the
ZhS-32 type should be crushed by high-temperature melting with aluminium granules. Aftermelting for 0.5 h in an induction furnace at 1500-1700oC we obtained a homogeneous alloy of ~4kg charge mixture with a mass ratio of m(alloy):m(Al) ~5:1. The nickel base of HRA wasconverted to aluminide Ni3Al, easily broken at low temperatures, so that the cooled melt could beground in standard facilities such as a jaw crusher and disc attritor. The resulting material had thegrain size of about 315 um (~95 w/o), most of which (81.6%) was 200-315 um. Table 1
demonstrates the chemical analyses of the initial and dispersed products.

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Table 1. Chemical composition of initial and ground HRA wastes.
Product
Content of elements, mass %
Ni
Co
Cr
Mo
W
Re
Initial HRA
61.0
9.0
4.9
1.0
8.5
2.6
Ground HRA
48.0
6.3
3.1
0.9
6.5
1.5

Al
5.9
32.0

Ta
2.1
1.1

Nb
1.6
0.7

We have tested two variants of acidic leaching of rhenium-containing HRA wastes: in oxidizing
conditions (whereby rhenium passes directly to solution) and without an oxidizer, resulting inrhenium concentration in leaching residue.
For acidic leaching of the alloy base without an oxidizer, sulphuric and hydrochloric acids wereused. The process was carried out for 3-6 hours at T=80ºC until completion of the reaction of metalcomponents with mineral acid. When 2-5 mole/L H2SO4 solutions and 5-6 mole/L HCl solutions
were used, more than 90 mass.% of the nickel base was dissolved, with but a small part of rhenium
passing to solution (1.2-5%). The solid phase diminished by
80-90 mass.%, which madepossible to concentrate much of rhenium in the insoluble residue, where its content was about 10
mass.%.
It should be noted that hydrochloric acid is preferable in this case because at later stages the nonferrous metals are easy to separate in chloride media. In particular, solvent extraction can be applied
to hydrochloric solutions containing 5-6 mole/L Cl- to isolate cobalt with tertiary amines.
It has been proposed to isolate rhenium from the leaching residue (solid-phase rhenium
concentrate), mostly containing Re, Nb, Ta and W, by using high-temperature distillation of Re2O7.
The best result in Re2O7 distillation in an oxygen flow was achieved at 950ºС, when 99.1% Re was
extracted in 1 hour. After 3 hours, up to 99.8 Re was extracted. Since the sublimate also contains
molybdenum, it can be dissolved in water and separated by solvent extraction methods with di-2ethylhexylphosphoric acid (D2EHPA).
Rhenium extraction to solution is considerably improved by adding an oxidizer at the stage acidic
leaching. Since subsequent Re extraction from solution is best performed in a sulphuric acidmedium, the leaching was conducted in the presence of an oxidizer by 5-6 mole/L H2SO4 at
S:L=1:15 and the temperature of 70-80ºС. During the first 2-3 hours the process occurred withoutan oxidizer, which was added after the bulk of metal components had reacted with H2SO4 (for 1.5-3h). The oxidizer solution was fed by batches using a peristaltic pump at a rate sufficient to maintainthe desired ORP value measured relatively a saturated chlorine-silver electrode.
Additional experiments on optimizing the oxidizer consumption have shown that efficient Re
extraction requires hydrogen peroxide in amounts needed to maintain the ORP system at the levelof 0.55-0.75 V for 2-3 h, resulting in diminishing of H2O2 consumption compared to tentative
experiments.
Fairly concentrated H2SO4 solutions are needed for effective leaching of the non-ferrous metal baseand also for obtaining of solutions acidic enough to selectively extract rhenium by solvent
extraction with secondary aliphatic alcohols [4].
In particular, we have tested 2-octanol, a reagent made in Russian. Reagents of this type featurehigh capacitance in rhenium (~100 g/L) selectively extracting it in sulphuric acid media in thepresence of molybdenum and other non-ferrous metals, which allows to isolate Re from solutions ofcomplex salt composition.
Laboratory experiments on extraction from leaching solutions were conducted in glass separating
funnels (0.25-0.5 L) under mechanical agitation at room temperature (20±2ºС). To prevent
additional acid extraction from leaching solution, the extragent was initially saturated with H2SO4.
The time of phase contact at all operations was 5 min, the O:A ratio was 1-5:1 depending on
operation. As the result of the laboratory experiments, extraction from leaching solution of HRA
wastes containing, g/L: Ni-21.8; Co-3.0; Al-15; Cr-1.4; Mo-0.36; W-0.25; Re-0.75 and 3.7 mole/L
H2SO4 , at one stage at the О:A ratio equal to 1:1 yielded 97.3% Re and 19.4% Mo to the organic
phase. By single washing at О:A=5:1, 61.9% molybdenum and a greater part of co-extracted H2SO4
were stripped, together with an insignificant quantity of rhenium. So, stripping with a 3 mole/L NH3
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solution produced a purified rhenium-containing solution with Re concentration of 0.5 g/L andmolybdenum concentration of 0.03 g/L. The level of Re extraction to ammonium concentrate was~80%.
Apparently, rhenium losses with wash water can be prevented by returning it to the process, either
to the extraction stage or to the stage of leaching solution preparation.
Lump waste
Melting

Al,
T~1650ºC

Grinding
H2SO4
+H2O2
Residue to Oxidation acidprocessing

Residue O2

H2O

Co striping

Re2O7 oxidation

Re SX

CoCl2 solution
distillation at 950ºC

H2O
NH4OH

Sublimate catching

H2O

Re striping

and dissolution
рН-correction

H2SO 4

Ammonium
Precipitation
perrhenate
Octanol-2

H2SO4 SX

Rafinate

Washing

Evaporation andcrystallization

H2O

octanol-2
Co SX

Solution

Acid leachingleaching
Solution

Octanol-2
with H2SO4

TOA+

HCl

D2EHPA+octanol-2
Mo SX
H2O2

NH4OH

Raffinate

Mo striping

Neutralization

H2SO4 striping
Technical-grade
H2SO4

Evaporation andcrystallization

NH4OH
Neutralization

Evaporation andcrystallization
Ammonium
perrhenate
Ammoniumparamolybdate

Fig. 1 Hydrometallurgical technology of rhenium- containing lump HRA wastes

By carrying out extraction at a laboratory cascade of mixer-settler extractors made in ICTREMRM
KSC RAS in the counter-flow regime, with wash water returned to extraction, we managed toincrease the rhenium yield from leaching solutions of rhenium-containing alloys. Extraction was
conducted at a 3-stage cascade at O:A=1:2, whereupon the extract was washed with an acidified
water solution (stage1) at O:A = 5:1. Re-extraction was carried out by a 3 mole/L NH3 solution at
О:A=3:1. From about 5 L of leaching solution containing, g/L: Ni-30.2; Co-4.2; Cr-3.1; Mo-0.6;
W-0.01; Re-2.0 and 4.5 mole/L H2SO4, an ammonium re-extract containing 12 g/L Re wasproduced. After evaporation, the resulting NH4ReO4 was purified from main impurities.
Our testing has revealed the possibility of selective solvent extraction of rhenium from leachingsolutions of HRA resulting in a purified ammonium perrhenate. This hydrometallurgical technologyof rhenium recycling from HRA waste has been covered by an RF patent [5].
Conclusion
As the result of this work, 2 variants of rhenium recycling from Re-containing HRA wastes,
providing for not only rhenium extraction but also a possibility of comprehensive processing ofwastes have been proposed. The schematic diagram of these processes is presented in Fig.1.
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References
1. http://www.catalysts.basf.com
2. http: // www.lipmann.co.uk
3. A. G. Kasikov, A. M. Petrova Rhenium recycling from heat-resistant and special alloy wastes(rus). Tekhnologiya Metallov. 2: 2-12, (2010).
4. RF Patent 2330900, MPK S22V 61/00, S22V 3/26. A method for rhenium(VII) extraction froman acid solution / A. G. Kasikov, A. M. Petrova (RF).– №2006142845/02; Appl. 04.12.06; Publ.
10.08.08. Bull. № 22.
5. RF Patent 2412267, MPK S22V 61/00. A method for rhenium recovery from metallic wastes ofnickel-containing heat-resistant alloys / A. G. Kasikov, A. M. Petrova, E.G. Bagrova, N. V. Serba,
V. T. Kalinnikov (RF).– №2009145364/02; Appl. 07.12.09; Publ. 20.02.11. Bull. № 5.

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3.P12.
INSTALLATION FOR LIQUID-LIQUID EXTRACTION CONCENTRATING
AND RECOVERY OF RHENIUM
FROM AQUEOUS SULFATE SOLUTION
A.M. Safiulina, K.E. German, N.N. Popova, M.Yu. Burtsev.
Academinvestservise Ltd., JSC NPO Innovation and development

Liquid-liquid extraction is a powerful method for separation of rare metals in course of its
hydrometallurgical reprocessing. It is widely used in course of technetium separations in the
reprocessing of spent nuclear fuel. Its application for the separation of rhenium – a close neighborof Tc in the Periodic Table – is considerably less abundant as the sorptive technologies are welldeveloped [1].
Although less abundant, the extraction separations of Re are also known and used for example inthe case of separation of Re from W in its nucleus generator [2].
Here we present an installation that could be applied to liquid-liquid extraction concentrating andrecovery (LLEC-I) of Re from aqueous sulfate solution.
The principle blocks of the LLEC-I include the clarification blocks (CS 1, 3), LLE and stripping
block (LLESB, 2), precipitation block (PB, 4). In a special installation modification LLEC-I-C theconversion block (CB, 5) is adopted.
The CS block is based on a know-how spiral principle. The LLESB is a conventional extractor,
while PB is presented by two modifications (C – a conventional one, and M – equipped with amelter of special design with know-hows and a patent providing with the possibility of meltedorganic perrhenate separation.
References
1. Pallant A.A., Troshkina I.D., Chekmarev A.M. Rhenium metallurgy. M.: Nauka Publ..
2007. 298 p.
2. M.P.Zykov, A.T.Filyanin, G.E.Kodina, A.Yu.Tsivadze, V.N. Romanovsky et.all., 2011,
This issue.

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3.P13.
RECOVERY OF RHENIUM FROM OIL SHALE
I. D. Troshkina, M.V. Vazchenkov, A. M. Chekmarev
D. Mendeleyev University of Chemical Technology of Russia,
Miusskaya Sq. 9, Moscow 125047, Russia. E-mail: tid@rctu.ru,

Carbonaceous source which is represented by a large group of minerals, such as oil, bitumen,carbon, oil shale (OS) is a non-traditional potential raw material of rhenium. Since the deposits ofthese minerals run into milliards of tons, the rhenium resources in them are great, in spite of therelatively low rhenium concentration. Data on rhenium content in carbonaceous raw materials are
relatively scarce and contradictory, although all of them considerably exceed its abundance ratio in
the crust (7.10-4 g/t by A.P.Winogradov).
Rhenium is found in solid combustible minerals enriched with Mo, V, Cu and U. This
complex of microelements is more characteristic of oil shale than of the coal. Comprehensive
energy-technological processing of metalliferous oil shale with complete utilization of organic andmineral parts includes their thermal treatment for production of electric and heat energy, chemical
products, metals, and building materials. Traditional methods for the thermal treatment of OS are
pyrolysis, semicoking, heat dissolution.
Rhenium distribution at high temperature combined processing of oil shale (OS) - oxidizing
pyrolysis and the semicoking was studied. The semicoking of OS (Uzbekistan) was performed at
the pilot device with solid heat-transport medium at 750C, the pyrolysis –in the reactor at universal
device. The oxidizing pyrolysis of OS at 750-800 C results in extensive decomposition of theorganic substances, which presumable incorporate rhenium. Rhenium heptaoxide, which is a highly
volatile compound, passes into the gaseous phase and concentrates in the coke (84.7%). During thesemicoking, the main part of rhenium also concentrates in the solid product_semicoke (60.0 %).
Rhenium recovery from the coke was investigated. The rhenium leaching from the coke bywater was carried out. Rhenium is successfully recovered from obtained solutions by sorption on
active carbon, modified active carbon and anionite. The sorption degree of rhenium was reached 50% (active carbon BAU), 94.6 % (modified active carbon) and 99.4 % (anionite).

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Tc and Re in Nuclear Medicine

The chairman of the 4th Section G.E. Kodina and K.E. German at the social dinner –short time to relax

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4.1.
Tc-99m AND Re-188 IN RUSSIAN NUCLEAR MEDICINE
G.E.Kodina
Burnazyan Federal Medical Biophysical Center of FMBA Russia;
123182, Moscow, Zhyvopisnaya,46; e-mail: gkodina@yandex.ru

The main tendency of modern nuclear medicine is substantial growth of radiopharmaceuticals(RP) using for therapy, first of all in oncology, but at a proceeding expansion of diagnostic RP.
Thus, despite of rapid development of PET quantity of diagnostic procedures with 99mТс SPECTand SPECT/CT also continue to grow.
New line for fission 99Мо production started at the end of 2010 in RIAR (Dimitrovgrad). It has
allowed to liquidate a problem of 99Мо deficiency in Russia and a significant amount is alreadyexported. There are 3 enterprises on 99mТс-generators (chromatographic type) production in ourcountry – at IPPE and BPCI (Obninsk) and at PTI (Tomsk). New manufacture of the generators on
GMP requirements is projected in Obninsk at the near future. Exstraction generators providing
centralized deliveries of a Na99mТсO4-solution work in Moscow, St.-Petersburg and Tomsk.
Capacities of operating manufactures are quite sufficient for full satisfaction of the Russian clinics
and capable to increase release of generators significantly. Growth of volumes of release restrains
with lack of the equipment in hospitals as well as unsatisfactory schemes and time of delivery tosome Russian regions.
99m

Тс-kits are let out by DIAMED Ltd. (Moscow), certificated according to requirements GMP.
The enterprise during 20 years completely satisfies needs of domestic and NM-departments andalso is capable to increase volumes of release significantly. It is necessary to note, that to 2008 thevolume of kits supplied to domestic clinics has returned on a level which has been reached up to adefault (1998г.), but is not observed growth (for the reasons specified above) not looking at
expansion of the nomenclature further. Nowadays the list includes 13 positions. Analysis ofchanges in 99mТс-kits usage for diagnostics of various diseases is resulted in the report.
Among last development of new 99mТс-RP, introduced in manufacture or clinical trials it isnecessary to note « Resoscan, 99mТс» (for osteoscintigraphy, on the base of zoledronic acids) and«Nanotech,99mТс » (nanocolloid for sentynel lymph nodes visualization).
188

Re-Generators are let out by IPPE (Obninsk). R&D on 188Re production in a centrifugal
extractor are spent in KRI (St.-Petersburg) in collaboration with IPCE RAS (Moscow).
Preclinical trials of «Zoleren,188Re» (188Re-zoledronic acid for therapy of bone metastasises)
are starting in June, 2011 and then clinical trials will be held in 2012. The RP was developed in
FMBC under the order of JS-Company «Pharm-Sintez». The R&D program on creation of 188ReRP for radiosynovectomy is begun this year.
As a whole it is possible to conclude, that in Russia there are necessary and sufficient conditions
for progress and development of new technologies for nuclear medicine with use both 99mТс, and
188
Re. Researchers and manufacturers of generators and RP on the basis of these radionuclides
hope, that realization of the Federal program «Development of the pharmaceutical and medical
industry of the Russian Federation for the period till 2020 and the further prospect» as well as the
Project «Progress of nuclear medicine in the Russian Federation » will allow to expand significantly
researches and to increase volumes of release of already existing and new radiopharmaceuticals.

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4.2.
THE fac-{TcO3}+ CORE – A CHALLENGE FOR HIGH-VALENTTECHNETIUM CHEMISTRY
H. BrabandInstitute of Inorganic Chemistry, University of Zurich, Winterthurerstr. 190, 8057 Zurich, Switzerland

KEYWORDS: Radiopharmacy, Labeling, Cycloaddition, Biodistribution, Glucose
ABSTRACT:We report a protocol for the synthesis of [99mTcO3(tacn)]+ ([1]+) that is suitable for clinicaltranslation. Bioconjugates containing pharmacophores ([TcO(NO2-Imi)(tacn)]+ [2]+), artificial
amino acids ([TcO(Fmoc-allyl-His)(tacn)]+ [3]+), andglucose derivatives ([TcO(allyltetraacetylglucose)(tacn)]+ [4]+) were synthesized by cycloaddition strategies and fully
characterized (99Tc and 99mTc). These new Tc complexes are stable at neutral pH and demonstrate
the potential and flexibility of the (3+2) cycloaddition labeling concept. In addition to the synthetic
work, the first biodistribution study of [1]+ was completed. The biodistribution study suggests thestability of this complexe in vivo. Further it could be demonstrated that the high hydrophilicity ofthe [99mTcO3(tacn)]+ building block is a complement to the complexes of the fac-{Tc(CO)3}+ core.
INTRODUCTION:
The site specific conjugation of a metalloradionuclide like 99mTc to a targeting vector in a manner inwhich the product retains the affinity of the parent is challenging.
To address this issue, one can take advantage of the rich coordination chemistry of technetium.
Coordination of radio-metals to an appropriate and strong chelator, conjugated to a targeting
biomolecule (peptides, oligonucleotides or small molecules) is the most frequently applied labelling
strategy and known as the bifunctional chelator (BFC) approach.1 The BFC approach conveniently
enables screening of a large number of targeting molecules with one particular metal core for which
the chelator is designed. In the field of technetium chemistry, TcV and TcI cores have been widely
explored to prepare molecular imaging probes.2-5
The ability to create new Tc synthons paves the way for the development of new and effective
imaging probes that overcome the challenges of introducing a metal complex into a vector.
In this context, the TcVII core, fac-{TcO3}+ came into the focus of our recent research because it iscompact and can be coordinated to tripodal ligands. Besides the small size, complexes with the fac{TcO3}+ core display a unique reactivity, particularly in water, that can be used as a creative route
to preparing novel molecular imaging probes. With alkenes, complexes of the fac-{TcO3}+ coreundergo metal-mediated, vicinal cis-dihydroxylation reactions (alkene-glycol interconversion) via a(3+2) cycloaddition reaction.6 cis-Dihydroxylation reactions with [OsO4] have been known for along time,7, 8 with fac-{TcO3}+ complexes this reaction type enables a ligand-centered labelingstrategy as recently shown with a proof-of-principle study.9 However, fac-{TcO3}+ complexes areuncommon10-20 and their syntheses in water remained unknown until recently.21 To utilize the fac{TcO3}+ core for preparation of molecular imaging probes, a one step synthesis of the[99mTcO3(L3)]+ precursor is required. To address this need [99mTcO3(tacn-R)]+ (tacn-R = 1,4,7triazacyclononae or derivatives) were synthesized in moderate overall yield by the reaction of[99mTcO4]- with phosphines and tacn or tacn derivatives.9 We report a protocol for the synthesis of[99mTcO3(tacn)]+ and the preparation of bioconjugates using cycloaddition strategies. In addition to
the synthetic work, the biodistribution study of [99mTcO3(tacn)]+ was completed.

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EXPERIMENTAL:22
Synthesis of 99Tc complexes[99TcO3(NO2-Imi)(tacn)]Cl ([2]Cl): Complex [1]Cl (20 mg, 0.06 mmol) was dissolved in 4 ml ofdistilled water and 1-allyl-4-nitro-imidazol (9.8 mg, 0.06 mmol) was added. While stirring at 65°C,
the yellow reaction solution turned deep blue in a couple of minutes. After 2 h, heating was stopped
and the solvent evaporated to dryness by a slow nitrogen stream. Compound [2]Cl can be isolated
as analytically pure micro crystals. Yield: 28 mg (98%).
[99TcO3(Fmoc-allyl-His)(tacn)](BPh4) ([3](BPh4)): Complex [1]Cl (11 mg, 0.04 mmol) was
dissolved in 1 ml of distilled water and the Fmoc-protected 1-allyl-histidine (20 mg, 0.05 mmol)
was added. The reaction solution was stirred for 2 h at 60°C. Compound [3](BPh4) was precipitatedfrom the reaction solution by addition of Na(BPh4) (14 mg, 0.04 mmol). Yield: 38 mg (95%).
[99TcO3(allyl-tetraacetylglucos)(tacn)]Cl ([4]Cl): [1]Br (17 mg, 0.05 mmol) was dissolved in a
mixture of water and acetonitrile (1:1, 3 ml) and the protected monosaccharide allyl 2,3,4,6-tetra-Oacetyl-β -(D)-glucopyranoside (19 mg, 0.05 mmol) was added. The reaction mixture was stirred
overnight at ambient temperature. Blue crystals, suitable for X-ray diffraction analysis, wereobtained by the addition of Na(PF6) (8.4 mg, 0.05 mmol) to the reaction mixture and slow
evaporation of the solvent. Yield: 28 mg, 86%.
Synthesis of 99mTc complexes[99mTcO3(tacn)]Cl ([1]Cl): Polymer (10 mg) [Nova Syn® amino resin (90 m), coupled to tris(2carboxy-ethyl)phosphine hydrochloride (≈ 0.3 mmol∙g-1 resin) by standard SPPS technique] wastransferred with 1,4,7-triazacyclononane trihydrochloride (23.5 mg, 10-4 mol) to a vial, tightly
closed and flushed with N2 for 10 min. [99mTcO4]- (1 mL) eluate was added and the reaction mixture
heated for 1 h at 95°C. The reaction solution was cooled, the resin filtered and the solution
neutralized by the addition of NaOH (0.1 M). Based on the exact amount of used NaOH (≈ 90 l)the amount of distilled water was calculated and added to the [99mTcO3(tacn)]Cl solution to obtain aphysiological NaCl concentration. 5 mg DOWEX 1 resin were activated in three times 1 ml ofsaline solution until the solution was not acidic anymore. The resin was filtered and added to the[99mTcO3(tacn)]Cl solution. After 10 min at room temperature the resin was filtered and the[99mTcO3(tacn)]Cl solution was used for further biological studies. Radiochemical purity wasmeasured by HPLC. Yield 10 – 15%, radiochemical purity > 99%.
[99mTcO(tacn)(NO2-Imi)]Cl ([2]Cl): Compound [1]Cl (99mTc) was prepared by the method
described above. 1-Allyl-4-nitro-imidazol (15 mg, 0.1 mmol) was added to the physiologicalsolution of [1]Cl. The reaction mixture was heated to 60°C for 30 min. Compound [2]Cl was
isolated by semi-preparative column chromatography using PBS as mobile phase. Radiochemical
purity was measured by HPLC. Yield: 30%, radiochemical purity > 99%.
[99mTcO3(tacn)(Fmoc-allylHis)]Cl ([3]Cl): Compound [1]Cl (99mTc) was prepared by the method
described above. The Fmoc-protected 1-allyl-histidine (41 mg, 0.1 mmol) was added to thephysiological solution of [1]Cl and the reaction solution was stirred for 2 h at 60°C. Radiochemical
purity was measured by HPLC. Yield: 72%.
[99mTcO3(tacn)(allyl-tetraacetylglycos)]Cl ([4]Cl): Compound [1]Cl (99mTc) was prepared by themethod described above. The protected monosaccharide allyl-2,3,4,6-tetra-O-acetyl-β -(D)-gluco302

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pyranoside (39 mg, 0.1 mmol) was added to the reaction solution and the mixture was stirred for 19
h at 40°C. Radiochemical purity was measured by HPLC. Yield: 96%.
RESULT AND DISCUSSION:
The chemical properties of [99mTcO3(tacn)]+ [1]+ are attractive for developing molecular imaging
probes because of its small size, hydrophilicity, serum stability and its reactivity with alkenes. 9 To
evaluate the biological behaviour of [1]+ and to evaluate its suitability for preparing bioconjugates
via cycloaddition reactions, a protocol for the synthesis of [1]+ suitable for clinical translation wasdeveloped. An immediate challenge was the very high hydrophilicity of [1]+ and its separation fromunreacted [99mTcO4]-. After the preparation of [1]+ from [99mTcO4]- with 1,4,7-triazacyclononane
and a polymer bound phosphine (figure 1), the solution was neutralized and diluted with water toobtain an isotonic NaCl solution. Addition of a strong anion exchange resin (DOWEX 1) removed
residual [99mTcO4]- quantitatively within 10 min at room temperature. This convenient procedureallowed the isolation of compound [1]+ with a radiochemical purity higher than 99% (figure 1).

Figure 1: Synthesis of [99mTcO3(tacn)]Cl and its formulation for biological applications.

With this protocol for the synthesis of [1]+ it was possible to characterize the biological profile of[99mTcO3(tacn)]+ (figure 2) and to evaluate its suitability for preparing bioconjugates via
cycloaddition reactions.

Figure 2: Biodistribution of [1]+ in A431 tumor xenograft bearing mice.
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The biodistribution of [1]+ suggests the stability of this complex in vivo since decomposition to[TcO4]- would result in thyroid and stomach/gut accumulation which was not observed. The bioprofile of [1]+ corroborates the high hydrophilicity of the [99mTcO3(tacn)]+ building block because itshows rapid clearance of [1]+ and the product resides mainly in the bladder and urine with some
uptake and retention in the kidneys and liver. Thus [99mTcO3(tacn)]+ is a complement to the fac[Tc(H2O)3(CO)3]+ core which binds to blood pool proteins, thereby inhibiting a fast clearance fromthe body.23 [1]+ shows a similar route of excretion compared to the small fac-{Tc(CO)3}+ complex[Tc(tacn)(CO)3]+ reported by Suzuki et al. although [1]+ appears to be retained in the liver andkidney to a higher degree over three hours.24
To explore the potential and general utility of the new bioconjugation strategy, three classes ofvectors were bound to the fac-{99mTcO3}+ framework via a simple (3+2) cycloaddition: 4-Nitroimidazole as a hypoxia imaging agent,25 histidine to create a non-natural amino acid that can beincorporated into peptides and radiolabeled and a simple glucose derivative (scheme 1). Glucose isa particularly interesting biomolecule because of the search for 99mTc-based carbohydrates as acomplement to 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG).26-28
These reactions and the stability of the products demonstrate the flexibility and suitability of thisnew labeling strategy. In vivo studies with these new compounds and the preparation of other new
radiopharmaceuticals derived from this core are currently under way.

Scheme 1: Labeling of 1-allyl-4-nitro-imidazole, 1-allyl-L-histidine and allyl-2,3,4,6-tetra-O-acetyl-β-(D)glucopyranoside with [99mTcO3(tacn)]+ via (3+2)-cycloaddition.

CONCLUSION:
The preparation of [99mTcO3(tacn)]+ in high radiochemical purity introduces a new synthon for the
preparation of molecular imaging probes. The in vivo study with the parent [99mTcO3(tacn)]+demonstrated that the compound is stable in vivo and is rapidly excreted, in contrast to thepharmacokinetic profile observed for [99mTc(H2O)3(CO)3]+. The reactivity of [99mTcO3(tacn)]+
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towards alkenes represents a convenient and efficient technique for labelling biomolecules througha (3+2) cycloaddition. To exemplify the versatility of the labelling procedure, three principally
different biomolecules were linked to the fac-{99mTcO3}+ core. These include a hypoxia targeting
pharmacophore, an amino acid analogue and a glucose derivative. We demonstrated that the highhydrophilicity of the [99mTcO3(tacn)]+ building block is a complement to the complexes of the fac{Tc(CO)3}+ core which are generally hydrophobic.
It has to be emphasized that the high-valent chemistry of technetium is not only relevant from aradiopharmaceutical point of view, but also with respect to the significant amounts of long lived99
Tc produced in world`s nuclear power plants. The possibility of binding fac-{TcO3}+ compoundsvia (3+2)-cycloaddition covalently to a substrate, such as surface modified nanoparticles or resins,
without a ligand replacement reaction could pave the way for new opportunities in the field oftechnetium immobilization. Therefore, the direct activation of [99TcO4]- and its efficienttransformation into water stable fac-{TcO3}+ compounds is of great interest.
ACKNOLEDGMENT:H. Braband acknowledges financial support from the Swiss National Science Foundation,
Ambizione project PZ00P2_126414.
REFERENCES:
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Liu, S.; Edwards, D. S., Chem. Rev. 1999, 99, 2235.
Jurisson, S. S.; Lydon, J. D., Chem. Rev. 1999, 99, 2205.
Dilworth, J. R.; Parrott, S. J., Chem. Soc. Rev. 1998, 27, 43.
Pearlstein, R. M.; Davison, A., Polyhedron 1988, 7, 1981.
Kolb, H. C.; VanNieuwenhze, M. S.; Sharpless, K. B., Chem. Rev. 1994, 94, 2483.
Schroeder, M., Chem. Rev. 1980, 80, 187.
Braband, H.; Tooyama, Y.; Fox, T.; Alberto, R., Chem. Eur. J. 2009, 15, 633.
Thomas, J. A.; Davison, A., Inorg. Chim. Acta 1991, 190, 231.
Oehlke, E.; Alberto, R.; Abram, U., Inorg. Chem. 2010, 49, 3525.
Tooyama, Y.; Braband, H.; Spingler, B.; Abram, U.; Alberto, R., Inorg. Chem. 2008, 47,
257.
Supel, J.; Hagenbach, A.; Abram, U.; Seppelt, K., Z. Anorg. Allg. Chem. 2008, 634, 646.
Supel, J.; Abram, U.; Hagenbach, A.; Seppelt, K., Inorg. Chem. 2007, 46, 5591.
Thomas, J. A.; Davison, A., Inorg. Chem. 1992, 31, 1976.
Du Preez, J. G. H.; Gerber, T. I. A.; Gibson, M. L., J. Coord. Chem. 1990, 22, 33.
Herrmann, W. A.; Alberto, R.; Kiprof, P.; Baumgärtner, F., Angew. Chem. Int. Ed. 1990, 29,
189.
Banbery, H. J.; Hussain, W.; Evans, I. G.; Hamor, T. A.; Jones, C. J.; McCleverty, J. A.;
Schulte, H.-J.; Engles, B.; Kläui, W., Polyhedron 1990, 9, 2549.
Nugent, W. A., Inorg. Chem. 1983, 22, 965.
Davison, A.; Jones, A. G.; Abrams, M. J., Inorg. Chem. 1981, 20, 4300.
Braband, H.; Abram, U., Inorg. Chem. 2006, 45, 6589.
Braband, H.; Tooyama, Y.; Fox, T.; Simms, R.; Forbes, J.; Valliant, J. F.; Alberto, R.,
Chem. Eur. J. 2011, in press.
Egli, A.; Alberto, R.; Tannahill, L.; Schibli, R.; Abram, U.; Schaffland, A.; Waibel, R.;
Tourwe, D.; Jeannin, L.; Iterbeke, K.; Schubiger, P. A., J. Nucl. Med. 1999, 40, 1913.
Suzuki, K.; Shimmura, N.; Thipyapong, K.; Uehara, T.; Akizawa, H.; Arano, Y., Inorg.
Chem. 2008, 47, 2593.
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25.
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Chu, T.; Hu, S.; Wei, B.; Wang, Y.; Liu, X.; Wang, X., Bioorg. Med. Chem. Lett. 2004, 14,
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Bowen, M. L.; Orvig, C., Chem. Comm. 2008, 5077.
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P. A., Bioconjugate Chem. 2004, 16, 105.

Alesya Maruk presenting her report on 99mTc radiopharmaceuticals

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4.3.
NEW RADIOPHARMACEUTICALS BASED ON TECHNETIUM-99m
WITH BIFUNCTIONAL CHELATING AGENTS
A.Ya. Maruk, A.B. Bruskin, G.E. Kodina
Burnazyan Federal Medical Biophysical Center of FMBA Russia;
123182, Moscow, Zhyvopisnaya,46; e-mail: amaruk@list.ru

Currently, 99mTc is radionuclide of choice for the preparation of SPECT-radiopharmaceuticals(RP) in the whole world. 99mTc is eluted from the generator in the form of a solution Na99mTcO4,
and then subjected to reduction and complexation with ligands. The complexity of technetiumchemistry makes it necessary to search for new, improved and multifunctional complexing agents.
Particular attention is paid to ligands that can not only bind technetium, but also can be linked tobiomolecules such as peptides or monoclonal antibodies. Among these ligands, called bifunctionalchelating agents (BCA), best results are showed by DTPA (Diethylene triamine pentaacetic acid),
MAG3 (Mercaptuacetyltriglycine), and HYNIC (6-Hydrazinopyridine-3-carboxylic acid).
Published data on the synthesis and application of some peptides labeled with 99mTc using
HYNIC, and DTPA and MAG3 are reviewed. There were found changes in the behavior of
conjugates with the same peptide using different BCA. This suggests that the choice of BCA shouldbe the first stage of planning the development of each new BCA RP with technetium-99m.
As a biological basis for the creation of conjugates with different radionuclides (111In, 68Ga)
octreotide is often taken. Octreotide is an analogue of the somatostatin wich is accumulated incancer cells of neuroendocrine nature. It was found that the conjugates with 99mTc-octreotide are noteffective enough, and the peptide has been modified. The most successful results of suchmodifications are Vapreotid (RC-160) and tyrosine-Octreotide (TOC).
When comparing DTPA, MAG3 and HYNIC most researchers coincide that preference over
the other two BCA is given to HYNIC, which is caused, first of all, by its more suitable
pharmacokinetic properties. Nevertheless, data on biodistribution of all three BCA conjugates still
remain controversial.
The report also discusses published data on the choice soligand to HYNIC. The following
soligands are considered: tricine (1,1-bis(hydroxymethyl)ethyl)glycine), EDDA (Ethylene diamine
diacetic acid) and the mixture tricine with nicotinic acid. All these soligands provide obtaining of
peptides labeled with 99mTc, in good yield and stability. According to some reports, the best
pharmacokinetics (accumulation in tumors, the rapid excretion via the kidney) was detected in theRP with EDDA as soligand. With the data presented, it is clear that not only conjugates known
soligands (mostly tricine and EDDA) should be further developed, but also new ones should be
looked for. The peptide most advisable to use is TOC.

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4.4.
“Rezoskan, 99mTc” IN THE DIAGNOSIS OF METASTATICBONE LESIONS
V.N. Korsunsky, V.N. Oshchepkov, S.V. Shiryaev, E.Z. Rabinovich
A.I. Burnazyan FMBC,
N.N.Blokhin RCRC, Institute of Urology, "Farm-Sintez" Inc.

“Rezoscan, 99mTc” is the first kit used in the domestic and international practices forcommercial radiopharmaceuticals (RP) based on zoledronic acid, being intended for the diagnostic
of bone pathology by Single Photon Emission Computed Tomography (SPECT).
Our clinical studies provided with the data on the high diagnostic value of the drug enabling
to identify metastatic bone cancer patients. The primarily observed pharmacokinetic characteristicsof the drug, compared with those applied in the clinic counterparts, indicate that it is characterizedwith more rapid RP elimination from the body, low accumulation in organs and tissues at hightropism to sites of metastasis in the skeleton. It provide with higher sensitivity and resolution in
detecting metastatic lesions of the skeleton of variable nature.
Due to favorable pharmacokinetics, the “Rezoscan, 99mTc” SPECT examination is possible 1- 1.5 hours after administration of the radiopharmaceutical, whereas all the existing RP require atleast 3 hours waiting period before the patient bone scan examination. This ensures high economic
and technological efficiency and lower patient irradiation dose rates.
Using “Rezoscan, 99mTc” it was possible to identify both blastic, mixed, and, mostimportant, the lytic metastases in primary bone scan, that were not detected by commonly usedradiopharmaceuticals in clinics. It should be noted that in recent medical practice there were noother radioisotope diagnostic products providing with the possibility to detect lytic metastases in theskeleton.
The investigation conducted on a selected group of patients has shown that bone scanningwith “Rezoscan, 99mTc” allows control of skeletal metastases by means of therapy with zoledronic
acid combined with chemotherapy.
Based on the foregoing, we conclude that the drug “Rezoscan, 99mTc” significantly differsfrom the previous generation of diagnostic radiopharmaceuticals and it has prospects for wider use
in clinical practice.

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4.5.
OBTAINING TECHNETIUM-99M LABELED NANOCOLLOIDS BASED ON
ALUMINUM OXIDE FOR MEDICAL DIAGNOSTICS
V.S. Skuridin, V.L. Sadkin, E.S. Stasiuk, N. V. Varlamova,
A.C. Rogov, E.A. Nesterov
National Research Tomsk Polytechnic University
634050, Russia, Tomsk, Lenina, 30. E-mail: svs1946@rambler.ru

In recent years, labeled with technetium-99m (99mTc) nanosized colloids of various
compositions are widely used in medicine for the diagnosis of inflammatory processes, theidentification of "sentinel" lymph nodes in cancer patients, for labeling autoleukocytes etc.
Presupposition for using aluminum oxide as a "carrier 99mTc label is its relatively low toxicity,
combined with good adsorption properties, availability and low cost. As the object of research, weused gamma-Al2O3 nanopowder with a particle size of 7 nm obtained from aluminum hydroxide bycyclic heating to 500°С.
In order to obtain stable compounds of 99mTc with Al2O3 oxide there was previously studied
the effect of acid activation of oxides on the value of their sorption capacity in relation to 99mTc
which has different degrees of oxidation in static conditions for adsorption. As a reducing agent tin(II) chloride dehydrate (SnCl2 ∙ 2H2O) was used. As a result, it was found that the maximum
adsorption of 99mTc is observed on oxides Al2O3, treated with HCl solution on the basis of 2 · 10-4
mole per 1 g of oxide, which corresponds to pH 5.6 colloid. In these conditions the adsorption of99m
Tc (VII) ions is about 30%, and of reduced ions of 99mTc (IV) – more than 90%. The method offiltering the resulting product through a filter with a pore diameter of 100 nm revealed that in thelatter case, the output of labeled nanocolloid exceeds 98%. In this case, adsorbed on oxide 99mTc(IV) is not washed off with saline (0.9% solution of NaCl), which indicates the stability of thecompound. The investigation of the chromatograms showed in the resulting product apart to 99mTc(VII) the presence of two reduced forms of 99mTc. Perhaps one of them is 99mTc (V).
Medicobiological tests of 99mTc labeled oxide Al2O3 were conducted on “Vistar” line whitemale-rats with weight 300-350 g. Inguinal lymph node in all the animals clearly visualized in 15
minutes, when it accumulated from 1,2 to 2,1% of introduced amount of labeled colloid. This shows
the principal possibility of using the obtained compound for conducting lymphoscintigraphy.

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4.6.
RECEIVING OF NANOSIZED COLLOIDS BASED ON MODIFICATEDDTPA MOLECULE LABELED WITH TECHNETIUM-99m
E.A. Nesterov, V.S. Skuridin, M.L. Belyanin, J.V. Nesterova,
V.L. Sadkin, A.S. Rogov, I.V. Chikova
National Research Tomsk Polytechnic University, Russia, Tomsk, Lenin Avenue, 30, nesterov_evgeny@mail.ru

Currently, the significantly intensification of interest to use of radioactivity colloid
nonmaterial’s in medicine is note all around the world. Radioactivity nanocolloid
application in oncology is based on quick and effective ability of «sentinel» lymph nodes
detection.
Optimal method of «sentinel» lymph node detection is consider in use of colloid
nonmaterial’s marked by technetium-99m for scintigraphic or radiometric detection of nodelocalization. Rich coordination chemistry of technetium can obtain on its basis the various
simple and complex, biologically active coordination compounds with desired properties.
As a result of the spent researches the methods of receipting of new nanocolloid based
chemical systems on basis of modification of diethylene triamine pentaacetic acid (DTPA)
molecule has been worked out. The main factor, which is affect on using DTPA as chelatorof radioactive mark, was molecule or one’s derivative ability to form enough stablecomplexes with different radioactive metals including combination of technetium-99. The
DTPA molecule hydrophilic and that’s why one can’t form colloidal particles. Hydrophilic
fragments addition gave the ability to receive insoluble’s modified complex of DTPA.
Preliminary research of compound transmission density, show’s that the middle radiusof generated colloids is near 100 nanometers. But the middle radiochemical emission of
nanocolloid, which have the diameter less than 100 nanometers, is about 80%, and this is
closed to foreign analogs rate.
The result of dynamic scintigraphic research showed, that after being injected, thepreparation goes to lymphatic system very active. Eventually one can say that modify
nanocolloids are functionally suitable for lymphoscintigraphy and « sentinel» nodevisualization.
That work has been carried out in the network of federal program «Scientific andscientific-pedagogical manpower of innovated Russia for 2009-2013»

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4.7.
SYNTHESIS AND COMPLEX ANALYSIS OF BIOLOGICALLY ACTIVEPOLYMERS (POLY-N-VINYLPYRROLYDON) WITH THE Re(CO)3
SPECIES.
N. I. Gorshkov1, A. Yu. Murko1, Yu. I. Zolotova.1, O. V. Nazarova1, I. I. Malakhova 1, V. D.
Krasikov 1, R. Schibli2
1
2

Institute of Macromolecular Compounds RAS, St.-Petersburg, 1999004, Bolshoi pr VO, 31 , Russia
Institute for Pharmaceutical Sciences ETH Hönggerberg, HCI H425 Wolfgang-Pauli-Strasse 10 CH.8093 Zurich,
Switzerland

Key words: bioactive synthetic polymers (BASP), rhenium, radiopharmaceuticals, HPLC,
spectroscopy
Abstract
Poly-N-vinylpyrrolidone derivatives with attached iminodiacetic groups were prepared in a wide
range of molecular masses (9 000 – 30 000 Da). Labeling of polymer carrriers with the “cold”
Re(CO)3+ species were performed under mild conditions. Metallo-polymeric conjugates werecomprechensively characterized by means of spectroscopic methods (IR, NMR, ESI-MS) and alsowith HPLC. Special attention was payed to the choice of stationary and liquid phases for HPLC
procedure, because it is extremally important for the further analysis of radiolabeled polymericsystems.
Introduction
Over the last 15 years chemistry of organometallic species, M(CO)3+ (M = Tc, Re) was
intensively studied. This interest grew up due to promising properties of this organometallic
fragment: relatively small size and low metal charge of metal atom (+1) [1]. Potentially, theseparameters should not disturb biological properties of organometallic biocojugates. However,worldwide practice of synthesis of low molecular compounds labeled with the M(CO)3+ fragment
and biodistribution studies demonstrate significant decreasing of specific site transport ofconjugates and accumulation of radioactivity in non target organs. More successful was introducingof organometallic species into macromolecular native biomolecules (antibodies, proteins) [2].
Targeted delivery of effector functions and moieties to diseased sites in the human body for
diagnostic or therapeutic purposes is a hallmark of modern drug development. Monoclonal
antibodies (MAb) has become an indispensable tools in this respect. However, the development andproduction of such macromolecules is extremely expensive and as a consequence such drugs are
growing burden for the health system. Hence, less costly alternatives have to be developed andinvestigated which combine the positive biological and pharmacological features of antibodies withthe lower costs of development of small molecules. Possible alternatives could be biologically
active synthetic polymers (BASP).
The major advantages of BASP in contrast to natural macromolecules (e.g. antibodies) are:(i) the possibility synthesis of polymers with relative narrow molecular mass distribution, (ii)possibility of regulation sites for attaching of biological vector and (iii) to attach one or several
radiometal fragments to bioconjugate (if desired to achieve high specific activity) (iv) low cost andpossibility to perform radiolabeling in one step procedure without complicated additional
purification. Last point is urgent for routine clinical application.
In the work we present an approach for labeling of biologically active synthetic polymers(BASP) with the M(CO)3+ fragment. To our knowledge literature data for radiolabelabeling ofgrafted BASP are scarce.
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We propose combination of macromolecular pharmaceutical chemistry andradiopharmaceutical chemistry for the development of novel, more efficient and less expensive
targeted radio-polymers (BASP) useful for tumor diagnosis and therapy. Polymer-carrier poly-Nvinylpyrrolidone was chosen due to its known pharmacological properties [3]. Polymers with
attached chelation iminodiacetate (IDA) groups were synthesized in a wide range of molecularmasses (9 000 -30 000 Da). IDA is known as effective chelation system for linking of M(CO) 3
species [4]. Special attention was payed for chromatographic analysis of metallo-polymericconjugates, due to it is a single method for determinetion of radiochemichal purity of resulting
radiopharmaceuticals.
Experimental.
All chemical reagents have pure and HPLC grade quality and were purchased from (NevaReactiv, Cryochrom, Reachim (Russia) and Sigma-Aldrich, Merck (Germany).
Spectral measurments were performed on IR FSM 201 unit (Russia), NMR spectrometer
Bruker AM 500 (Germany), pilot ESI MS unit (Institute of Analytical Instrument-Making RAS,
Russia). Chromatographic analysis was perfomed on the multidetector HPLC system (Knauer,
Germany). Ultrashort monolithic CIM (Convective Interaction Media) columns (Austria) were used
as a stationary phase, elution system - 0.1% TFA aqueous buffer, flow rate – 0.3 ml/min, detection:
210, 230, 254, 280 nm, RI.
Synthesis of aqueous solution of [Re(CO)3(H2O)3]Cl was performed according to thepreviosly described procedure [5] (scheme 1).

Scheme 1: Synthesis of the organometallic precursor [Re(CO)3(H2O)3] +.[2]Synthesis of iminodiacetate-poly-N-vinylpyrroidon was done according to previosly developed
procedure [3] (scheme 2)

Scheme 2: Preparation of PVP comprising exclusively the metal chelating system IDA (2) and the synthesisof mixed PVP comprising free primary amine functionalization (3) - for subsequent attachment of targeting
molecules and formation of biologically active synthetic polymers (BASP) - and the metal chelating system
IDA

Contents of free aminogroups in co-poymers were performed by means of potentiometrictitration with the 0.1M HCl. Data on characterstic viscosity were obtained in 0.1 M sodium acetate
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aqueous solution at 25oC. Molecular masses were evaluated according to Mark-Howink constants
for unmodified PVP. (Tables 1, 2)
Table 1. Polymerization conditions and characteristics of polymers obtained at Stage I
Polymerization conditions

Characteristics of amino co-polymers[VP] : [АА][VP] : [АА]Mass.%[DINIS],Conc.
vass.%%
Mol.% from mon.

1

66 : 34

50 : 50

1

50

20

0,10

13000 93,7 : 6,3 88,4 : 11,6

2

82 : 18

70 : 30

1

50

43

0,16

30000 97,1 : 2,93

66 : 34

50 : 50

1

50

20

0,08

9000

№

Mass.%

[η],
dl/g

Мη

Mol.%

94,4 : 5,6

93,8 : 6,2 88,5 : 11,5

Table 2. Polymerization conditions and characteristics of PVP-IDA copolymers obtained at Stage II

Starting amino-co-polymer

Resulting PVP-IDA co-polymer

№

[АА],
Mol.%

[η], dl/gМη№.

[IDA], Mass.
%[IDA], Mol %

1

11,6

0,10

13000

4

5,8

6,6

2

5,6

0,16

30000

5

5,7

6,5

3

11,5

0,08

9000

6

5,8

6,6

Metall-polymeric conjugates were synthisized under various conditions: at ambient
temperature (2-3 days), 60-70 C (2-3 hrs), microwave activation (3 min, 450 Wt), at pH≈7. Final
product was purified by membrane dialysis, lyophilic drying and charcterized by spectral andchromatographical methods.
Result and Discussion
On the preliminary stage of our research we concentrated our efforts on organic synthesis ofmodel poly-N-vinyl pyrrolidone (PVP) biofunctionalized with metal chelating systems suitable for(radio)labeling with organometallic precursors of the element technetium and rhenium([M(CO)3(H2O)3]+ M = Tc, Re). This water soluble precursor has been reported to coordinate with awide variety of metal chelating systems comprising various donor groups. The organometallic
precursor [Re(CO)3(H2O)3]+ was prepared starting from commercially available Re(CO)5Cl
according to the literature data [5]. This procedure was chosen in order to avoid presence of
undesirable salts (e.g. NEt4Cl), in contrast to the traditional [Re(CO)3Br3][NEt4]2 precursor [1],which could impair the subsequent reaction with the polymers and would be difficult to separate forthe desired product. The synthetic route is given in scheme 1.
In order to exclude any unwanted and unspecific labeling of PVP with the organometallic
precursors via the lactone groups we studied the coorindative behaviouor of the nonmodified PVP
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with [Re(CO)3(H2O)3]+. Reactions were followed by HPLC and products were purified bymembrane dialysis and lyophilic drying. The isolated product was characterized by IR. The IR
spectra revealed extremally weak bounding of organometallic precursor to PVB backbone. The
characteristic signals of the metal carbonyl were very weak indicating that the lactone rings
appeared to be weak chelating agents and are not able to efficiently form complexes with Re(CO)3moiety.
For functionalization of PVP with metal chelating systems N-vinyl pyrrolidone was reactedwith allylamine according to scheme 2. The corresponsing PVP (1) were reacted with chloro acetic
acid at 90°C at pH 10 for N-alkylation to form the bifuctionalited derivative (2). The iminodiacetate(IDA) derivative 3 was obtained in good yieldes. The range of attached IDA chelation groups varied
from 2 to 6 mass %. The purification was performed by dialysis and lyophilic drying. The polymers
were characterized by 1H-13C 2D NMR, viscozimetry, and IR spectroscopy. MS analysis further
revealed that the size distribution of the PVP ranged from 9 000 -30 000 Da (optimal range of
masses for the target biological transport).
In a parallel strategy we prepared modified PVP contained both IDA chelators and freeamino groups for further coupling of (tumor) targeting of small peptides (scheme 2).
In a second step we labelled the derivatives 2 and 3 with the organometallic precursor. The
reaction conditions have been optimized. Syntheses were carried out under different conditions: atambient temperature (2-3 days), 60-70 C (2-3 hrs), microwave activation (3 min, 450 Wt).
Complexation of organometallic complex was followed by HPLC fig.1. It could be shown, thatreaction strongly depends on pH (optimal value was estimated as Ph ≈7). The labelled polymers
were purified in order to remove undesired traces of buffer salts dialysis and lyophilized. The
products [Re(CO)3(2/3)] were characterized by 1H NMR, IR spectroscopy (fig.1).

0.8

0.6

Characterististic
vibrations ofRe(CO)3 group

0.4

0.2

Vibrations of polymer lactone
groups
0.0
500

1000

1500

2000

2500

3000

3500

4000

4500

Fig.1. IR characterization of conjugated PVP-IDA-Re(CO)3 co-polymers, KBr pellets. Red –[Re(CO)3Br3][NEt4]2 (as a reference), green- PVP-IDA-Re(CO)3 conjugate (sample 13 000 Da)

According to the presented data it is clear, that valent vibrations of noncoordinated Re(CO)3+
are significantly shifted contrastly to metallo-conjugated polymer with the Re(CO)3+ species.
Moreover, decreasing of vibrations of Re(CO)3+ in contrast to vibrations lactone rings confirms
quantatitative linkage of metallorganic fragment to polymeric matrix. This tendency was observed
to all range of studied conjugates and in the good agreement for published data for low molecularcompounds, labeled with M(CO)3 fragment [3].
Data of ESI mass spectrometry also confirms formation of metallo-polymeric conjugate(fig.3)314

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Fig. 3. ESI-MS for the PVP-IDA-Re(CO)3 conjugate (starting PVP-IDA -MW = 13 000 Da + 2 000Re(CO)3) Mz≈ 15 000 Da.

Special attention was paid for chromatographical analysis of reaction mixtures and final BASP
with incorporated Re(CO)3 species. It is well known, that chromatographic methods for analysis andpurification of radiolabeled compounds are the very effective tool. Therefore, a separate task ofcurrent work was to find an optimal conditions for separation using HPLC and HPTCL. At the
moment, for fast and efficient separation of reaction products (high and low weight molecularcomponents) ultra-short monolithic CIM (Convective Interaction Media, BiaSeparations, Austria)
exhibited most efficient properties. However, despite extremely short times of analysis (5 min), thistype of columns cannot provide information about the distribution of the analyths according to theirmolecular mass. In contrast, the originally prepared monolithic and silica modified HPTLC plates
have capability for identification all reaction products online. Furthermore, it was estimated that
employing traditional SEC HPLC on a known sorbents previously prepared in our group allows
separating polymeric species in a wide range of molecular masses. Typical chromatogram ofreaction mixture is presented below (fig. 4).

Fig. 4. Separation of artificial mixture of copolymer PVP-IDA-Re(CO)3 and Re(CO)3(H2O)3 on the CIMCM ultrashort column Elution system (0/1% TFA/methanol 50:50), UV detection (diode array) (210, 230,
260, 310 nm ), RI detection, flow -0.3 ml/min (absortion maximum of conjugate -210 nm). First sharp peakcorresponds to PVP-IDA-Re(CO)3 conjugate; second broad peak - Re(CO)3(H2O)3
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CONCLUSIONS
It was demonstrated that organometallic species are fully trapped by IDA chelation systemand produce stable metallo-poymeric conjugates. Moreover, it should be noted, that both types ofpolymers, 2 and 3, have the same coordinative properties, thus the free primary amine in derivative
3 does not seem to participate in the metal coordination (according to NMR and IR data).
HPLC system for separation of organometallic precursor and target polymeric conjugate,based on CIM technology, was developed.

AKNOWLEDGMENTS
This work is supported by SCOPES Project No. IZ73Z0_128443 and RFBR N 10-08-00963
Referenses
1. Alberto et al. J. Am. Chem. Soc. 120: 7987-7988 (1998);
2. Kirsch U. E., poly-N-vinylpyrrolidone and other poly-N-vinylamides, , Moscow, Nauka (inRussian)] (1998)
3. M. Welch, C. S. Redvanly. Handbook of Radipharmaceuticals.Wiley, (2003).
4. Schibli et al. Bioconjugate Chem. 13, 750-756. (2002)
5. N. Gorshkov et. al Radiochemistry 42, 231-235(2000).

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6. 4.8.

DEVELOPMENT OF DOSIMETRIC SUPPORT AND PLANNING OF
RADIONUCLIDE THERAPY WITH RADIOPHARMACEUTICALLABELED 188Re
A.N. Klyopov2, V.V. Krylov1, Y.A. Kurachenko2, Eu.S. Matusevich2, Eu.V. Snigirev2, O.P.
Aleksandrova2
1

Medical Radiological Research Centre of Ministry of Health, krylov@mrrc.obninsk.ru

2

Obninsk Institute for Nuclear Power Engineering of National Research Nuclear University MEPhI

Now in MRRC of Ministry of Health of Russian Federation is realized the program ofskilled-technological and preclinical tests perspective radiopharmaceutical labeled 188Re. For someof them carrying out of a phase of clinical researches in the near future is planned. With a view ofincrease of efficiency of medical technologies by employees INPE together with MRRC thecomplex of development in the field of individual dosimetric support and planning radionuclide
therapies of some diseases with radiopharmaceutical on the basis of 188Re is carried out. They
include: 1) development of techniques for dosimetry of critical organs (kidneys, bladder, blood,
red bone marrow, etc.) and target organs (tumours or metastasises) which, in turn, lean on offeredoptimum, and sparing for patients, protocols for clinical researches of radiopharmaceuticalpharmacokinetics (with light invasive and noninvasive techniques); the criterion of an optimality
here means use minimally necessary number of time measurements and an opportunity of
restoration of data about accumulation of radiopharmaceutical in those organs in which it is
impossible direct to carry out radiometry; 2) a substantiation and development of techniques formathematical (multichamber) modelling of radiopharmaceutical metabolism in an organism ofpatients, and realization of numerical identification of corresponding kinetic parameters - with the
purpose of restoration continual dependences of radiopharmaceutical dynamics, carried out on thebasis of the limited volumes of skilled data; 2) development of techniques of carrying out of singlephoton emission images in a problem of identification of activity 188Re, accumulated in amazed andhealthy organs of patients; in particular, development of mathematical models for target organs - thebone structures allowing with certain accuracy to restore distribution of activity in view of factorsof degradation single-photon emission images; 3) mathematical modelling of fields of absorbed
doses by a method of Monte-Carlo in the volumes of tumors and critical organs; 4) development ofRadiation Safety recommendations under scripts of patient’s contact with relatives after their
extract from hospital.
Results of numerical calculation of fields of absorbed doses in phantoms of tumours and also
results of variational modelling of radiopharmaceutical pharmakokinetics with 188Re in an
organism of patients with bone metastasises are resulted.

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4.9.
EDUCATION AND TRAINING IN NUCLEAR MEDICINE, RADIOPHARMACY, MEDICAL PHYSICS AND
MOLECULAR IMAGING: THE INSTN EXPERIENCED APPROACH
A. Hammadi
Atomic Energy Commission, Saclay Research Center, National Institute for Nuclear Science and Technology, 91191
Gif-sur-Yvette, France – akli.hammadi@cea.fr

Nuclear medicine, radiopharmacy, molecular imaging or related fields combine advanced
engineering in chemistry, nuclear science, molecular biology and physiology together with state-ofthe-art technology for non invasive in vivo imaging. This field contributes immensely tobiomedicine because it is the major technology that can explore and measure the chemistry of life ina non invasive manner. It is thus a key for the development of new diagnostics and therapeutics.
Considering the rapid development of technologies, there is an urgent need of specific educational
programs in these fields. Physicians, researchers and chemists must be well qualified andappropriately trained to adapt themselves to these new technologies. This must be achieved throughsuitable and updated trainings.
Since 1974, the National Institute for Nuclear Science and Technology (INSTN) within the
French Atomic Energy Commission (CEA) has been responsible for organising the theoreticaltraining of medical doctors, pharmacists, chemists and physicists in nuclear medicine,radiopharmacy and medical physics. This Institute is recognised by the European Association of
Nuclear Medicine (EANM) as a training centre in radiopharmacy. The INSTN provides solutions tosatisfy needs in nuclear medicine, radiopharmacy and molecular imaging training in therequirements from professionals. To do so, the institute is in charge of organising short trainings for
professionals (Life-Long Learners). It also brings training solutions to special needs for national
and/or international trainings. At last, the INSTN is deeply involved in the academic field.
Among the training courses provided by the INSTN, the new European Master in
Molecular Imaging (EMMI) offers an international program entirely dedicated to molecularimaging. Supported by the European Commission under the SOCRATES programme, this two
years interdisciplinary curriculum is brought together by prominent European molecular imaging
research groups, with the objective to prepare students for both academic and industrial positions.
Courses are held in parallel at the partners Institutions: the INSTN (Saclay, France) –coordinating, and the Universities of Paris Sud 11 (France), Antwerp (Belgium), Crete (Greece) andTurin (Italy). The curriculum includes courses on the basics of physics, chemistry, biology andphysiology for Molecular Imaging, advanced courses on each imaging technology (PET, SPECT,
MRI, OI, and ultrasound) as well as a full time six months immersion in one of over forty industrial
or academic partner laboratories around the world. In just two years, EMMI students acquire fulltheoretical and practical competences in all molecular imaging modalities. The master programmeis entirely held in English, built for students with a bachelor degree in biology, biomedical sciences
but also in physics, chemistry and computer science as optional bridging courses are offered inphysiology and biology.
Those highly specialized theoretical and practical courses, which are recognized byprofessionals, are open to students and employees willing to improve their professional
qualification in these fields. It would be clever to ask one or many Universities in order to face thesetting up of a middle-term academic training allowing the training of the future radio pharmacists.
Thus, Russia could be inspired by the trainings (INSTN) made for these professionals in France atthe present time.

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4.10.
HIGH SPECIFIC ACTIVITY RADIONUCLIDES IN NCA FORM:
Re-186g PRODUCED BY CYCLOTRON
M.L. Bonardi1, F. Groppi1, E. Lapshina2, S. Manenti1, L. Gini1
1

Università degli Studi di Milano, UNIMI and Istituto Nazionale di Fisica Nucleare, INFN,
L.A.S.A., Radiochemistry Laboratory, Via F.lli Cervi 201, I-20090 Segrate, MI, ITALY
2
Institute for Nuclear Research, 60th October Anniversary Prospect, 7A Moscow, 117312, RUSSIA

The 186gRe is a double purpose  and  emitter, that, thanking to its suitable chemical and nuclear properties:
T1/2 = 90.64 h; Emax = 1069.5 keV (74.3%) and 932.3keV (18.8%); main s at 137.155 (8.22%) and 122.58(0.56%) keV, is presently used in metabolic radiotherapy with palliative pain elimination of bone metastases
but it is a good candidate to be used in metabolic radioimmuno-therapy (RIT) combined with molecularimaging devices (i.e. theragnostics). Unfortunately this radionuclide cannot be used yet in RIT therapeutic
procedures, because its present production route - by radiative neutron capture on moderately enriched 185Re
in thermal nuclear reactor - leads to a relatively low specific activity AS, in carrier-added (CA) form. The
possibility to improve the use of this radionuclide is strictly linked to the possibility of increasing the A S,
approaching the theoretical carrier-free (CF) value of 6.88 GBq μg-1. A way is its production by proton ordeuteron bombardment on tungsten-186 targets via either (p,n) or (d,2n) nuclear reactions.
In order to assess the effectiveness of the W(p,n)186gRe and/or W(d,2n)186gRe nuclear reactions to produce
186g
Re in no-carrier-added (NCA) form, new sets of thin target excitation functions and experimental thicktarget yields for each RN were measured, at variable proton energies up to 22.0 ± 0.2 MeV and deuteronenergies up to 19.0 ± 0.2 MeV [1-3]. The experiments were carried out at first by using W targets of natural
isotopic composition. This leads to a production of a range of Re radioisotopes and to an effective 187W
“internal spike”. A first conclusion is that natural W is not a suitable target due to the low A S(NCA) andradioisotopic purity achievable, caused by the production of several other stable and radioactive nuclides ofRe and secondly that the production by deuteron beam is envisaged, due to the substantially higher yield.
Besides, a suitable radiochemical separation of Re isotopes from W and 186W targets and from 183Ta byproduct was set up for both proton and deuteron bombardments. A single radiochromatography method
based on activated acidic aluminum oxide (AAO) was adopted. The radiochemical recovery yield obtained ineach separation is greater than 98 % within the first 12.5 mL and the values reach 100 % within 15 mL ofsolution for a 100 mg W metal target. For W target weights up to 500 mg, the solution and column volumes
have been scaled-up. NAA and ET-AAS have been adopted for determination and quality control ofchemical purity and AS(NCA).

Acknowledgments: Special thanks are devoted to the staff of JRC-Ispra (VA, Italy) of EC for cyclotron
irradiations, INFN-GrV for financial support and Doctorate School in Physics, Astrophysics and Applied
Physics of the Università degli Studi di Milano.
References
1. Z.B. Alfassi, E. Persico, F. Groppi, M.L. Bonardi, Appl. Radiat. Isot., 67:240–242 (2009).
2. M.L. Bonardi, F. Groppi, S. Manenti, E. Persico, L. Gini, Appl. Radiat. Isot., 68:1595-1601 (2010).
3. M. Bonardi, F. Groppi, E. Persico, S. Manenti, K. Abbas, U. Holzwart, F. Simonelli, Z.B. Alfassi,
Radiochim. Acta, 99:1-11 (2011).

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4.11.
OPTIMIZATION OF PARAMETERS OF THE 188RE OBTAINING PROCESSIN A CENTRIFUGAL EXTRACTOR
M.P.Zykov1, A.T.Filyanin2, G.E.Kodina3, A.Yu.Tsivadze2, V.N. Romanovsky1, D.A.Tkachuk1,
O.A.Filyanin2, S.P.Orlov1, V.A.Novojilov1
1

Khlopin Radium Institute, 2Frumkin IPCE RAS, 3Burnazyan FMBC FMBA Russia; 123182, Moscow,
Zhyvopisnaya,46; e-mail: gkodina@yandex.ru

One of the most promising radionuclide for nuclear medicine is 188Re, a daughter of 188W. A mainfeature that distinguishes 188Re from most other therapeutic -emitters (for example, 90Sr) is the emission of asoft gamma-ray (15%, 155 keV). This makes it possible to monitor the distribution in tissues and organs
and, correspondingly, to calculate very accurately the therapeutic irradiation dose. Research on the RP basedon 188Re, which are already used or under development for therapy of several diseases, is being performed inmany leading countries.
The goals of this work were to study the use of the centrifugal extractor to isolate medical-grade 188Re
from 188W. The work included the manufacturing of the two-stage centrifugal extractor, the extraction of Re
from W by MEK from alkaline solutions, a determination of chemical impurities in the 188Re solutions, theconstruction in a hot cell of equipment for testing the process using actual solutions, a check of the selected
extraction conditions, and a determination of the optimal extraction conditions for preparing medical-grade
188
Re.
Reagents. The following reagents were used for studying the extraction of Re and W and for analyzing
solutions: KOH, WO3, and K2CO3 (ultra-high purity); acetone, CHCl3, and MEK (chem. pure). MEK was
distilled before use as an extractant. 188W was produced by irradiation of WO3 in the WWR-M reactor of
PNPI (Gatchina). The neutron flux 11014 ncm-2sec-1) is sufficient to prepare 1-2 Ci of 188W after irradiationof the target during 2-3 months.
Apparatus and process for preparing 188Re. The use of centrifugal extractors is advisable for highactivity solutions because they guarantee the minimal contact time of the high-activity aqueous and organic
phases. The apparatus for preparing medical-grade 188Re with these features was assembled. The shielded
box was constructed of steel 100 mm thick. The inner surfaces were lined with stainless steel. Work in thebox could be observed through a lead-glass window 150 mm thick. The irradiated WO3 is dissolved in an
alkaline solution containing KOH (2.5 M) and K2CO3 (2.5 M) and fed by pressure into the first stage of thecentrifugal contactor. MEK is fed into the first stage of the contactor using a peristaltic pump at 4 ml/min.
After passing through the first stage, MEK is scrubbed in the second stage and then is fed into theevaporating apparatus, equipped with a jacket through which hot water (85-95C) is circulated. After MEK
is evaporated the evaporating apparatus is flushed with air for 15-20 min to remove traces of MEK. At thispoint the evaporating apparatus contains 188Re. The appropriate aqueous solution is added from anintermediate tank to the evaporating apparatus to dissolve the 188Re. The solution is bubbled in the apparatus
for 3-5 min and fed through a filter into the vial-connector.
Results and conclusion. Tests of the equipment using model and actual solutions showed that the Re
yield is >85%, the radiochemical purity is >99%, the pH value of the aqueous 188Re solution is in the range
6.5 to 7.5, the content of radionuclidic impurities is <110-7, and the content of stable elements is determinedpractically by the quality of the aqueous solutions used to dissolve the 188Re. Such equipment can be a
prototype of a regional centralized generator of medical-grade
Acknoledgement. The work was partially supported by UNTC contract No. P437.

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4.12.
188

W/188Re GENERATOR PRODUCTION TECHNOLOGYFOR NUCLEAR MEDICINE
A.A. Semenova, N.G. Baranov, D.V. Stepchenkov, E.V. Sulim

State Scientific Center of the Russian Federation – Institute for Physics and Power Engineering,Bondarenko sq., 1,
Obninsk, 249033,Russia

KEYWORDS: nuclear medicine, rhenium-188, 188W/188Re generator, adsorbent, elution,and dynamic sorption, gamma-spectrometry.

static

ABSTRACTThe research was done, which aimed at the development of an innovative technology of the
production of 188W/188Re chromatographic generator – the first radioisotope generator in Russia fortherapeutic application. The generator activity is 100 – 1000 mCi in Rhenium-188.
INTRODUCTION
Rhenium-188 (188Re, T1/2 = 16.9 h) is considered to be of the perspective radioisotopes for betaradiation therapy in nuclear medicine. Rhenium-188 is produced via β-decay of tungsten-188 (188W,
T1/2 = 69.4 days) in a 188W/188Re generator.
188
W/188Re generator is a promising one for the application in nuclear medicine due to suitability of
nuclear and physical characteristics of Re-188 for therapy as well as thanks to the long enoughhalflife of W-188, which makes it possible to develop generators with a long service life (from 4 to
12 months depending on 188W initial activity).
Table 1. Specifications of 188W/188Re generator system

Daughter radionuclide
Isotope Decay Energy and
T1/2
type
intensity,
MeV
188
Re

- 2.12 max
16.9 h 0.155 (10%)

Isotope
T1/2
188

W
69.4
days

Parent radionuclide
Decay Energy andtype
intensity,
MeV
0.349 max
0.227
(0.22%)
0.291(0,4%)

Nuclearreaction

Eluent

186

0.9%
NaCl

W(n,)1
87
W(n,)18
8
W

The nuclear reaction of dual neutron capture of tungsten-186 by nuclei in a reactor with a highneutron flux 2 · 1015 neutron · cm-2 · sec-1) is used for producing tungsten-188. This radio-nuclide
is only produced in RIAR (Dimitrovgrad) in Russia and in Ok-Ridge in the USA.
The advantage of Rhenium-188 as a radionuclide for nuclear medical application is the presence ofboth beta- and gamma-components (0,155 MeV) of radiation because the first one determines atherapeutic effect, and the other one – imaging in common gamma-chambers that gives informationon the bio-distribution of drugs with Re-188.Radiopharmaceuticals based on the generator eluate
are synthesized in hospitals for beta-radiation therapy of malignant tumors, bone metastases,
rheumatoid arthritis, and other diseases.

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EXPERIMENTAL“Sodium tungstate (Na2WO4), 188W” was used as an initial raw material for carrying out the
research. This preparation was produced in RIAR (Dimitrovgrad) by irradiating tungsten trioxide(WO3) in “SM” high flux reactor with the neutron flux density of 2 ·1015 neutron · cm-2 · sec-1. In
accordance with the manufacturer’s certificate the specific activity of 188W was 2–7 Ci/g.
A working solution for sorption was prepared for carrying out the research. The initial “Sodium
tungstate (Na2WO4), 188W” with pH ~12–13 was conditioned to reach a required pH using thetitrated 1.0M and 0.01M hydrochloric acid; it was conditioned to reach a required concentration oftungsten by adding water for injection and 0.001M hydrochloric acid.
The sorption column was filled with an adsorbent – aluminum oxide (pH 4.5) in the quantity of 3.0–
6.0 g. The working solution of sodium tungstate, 188W (pH 2.0–3.0) was passed through the column
at the rate of 1.0 ml/min. Then the column was washed with 200ml of sodium chloride isotonic
solution. The elution of 188Re is performed by passing 5–15 ml of isotonic solution of sodium
chloride through the column every 3–4 days after 188W has been adsorbed. Radioactive
concentration of technological solution was measured using both dose- calibrator “Atomlab 100
Plus” and a semi-conducting gamma-spectrometer with Ge/Li detector.
RESULTS AND DISCUSSION
The study of 188W adsorption in static and dynamic modes
The method of radioactive tracers was used during the study of the sorption process for determining
a quantitative concentration of W in the experimental process solutions. Sodium tungstate(Na2WO4) solution with 188W radioactive tracer was used.
The following sorbents were used for studying 188W adsorption in the static mode: ZrO2, Al2O3,
SnO2. It has been found out that acid alumina in the acidic form is the most effective adsorbent.
Static adsorption
Al2O3 adsorbent (рН 4.5 Fluka) was used. Initial solutions with tungsten concentration of 1.0
mg/ml and different pH values were prepared. Tungsten solution with a radioactive tracer and theweighted portion of aluminum oxide were put into glass vials and, having mixed them thoroughly,
10 L samples were taken for radiometric measurements in 24 hours. The calculated values ofsorption for the taken samples are given in Table 2.
Table 2. The influence of pH of the initial and equilibrium solutions of tungsten sorption

No.
1
2
3
4
5
6

pH of initialsolutions
2.1
3.2
4.3
4.9
6.1
6.8

AVequilibr,
MBq/ml
0,23
0,29
0,40
0,59
0,74
0,88

Sorption of tungsten,
mg/g
111,7
101,7
83.3
51,8
26,7
3,3

pH of the equilibrium
solutions
2,4
4,6
5,2
5,0
8,1
8,2

Tungsten sorption was calculated by the formula:
Q (mg/g) = [( (1- AVequilibr/ AVinitial) CWinitial  VWinitial)]/ m Al2O3,
where: AVequilibr. – concentration activity of the equilibrium solution under study;
AVinitial - concentration activity of the initial solution;
VWinitial – a volume of tungsten solution, ml;
CWinitial – tungsten concentration in the initial solution, mg/ml.
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It follows from the results presented that the adsorption of W should be performed in an acidic
medium (pH 2-3).
Tungsten adsorption on acidic and neutral chromatographic aluminum oxide and calculation oftime that is necessary for reaching the sorption equilibrium
The experiment conditions. The initial solution of sodium tungstate (15 ml) and aluminum oxide in
the quantity of 150 mg were put in glass vials. Then samples of 10 L in volume were taken for
performing radiometric measurements each hour during the first three hours and then in 6 hours, 12hours, and 24 hours.
Tungsten concentrations in the equilibrium solutions were measured by the method of radioactive
tracers using gamma-spectrometry. The composition of the initial solution corresponds to thefollowing values: tungsten concentration Cw=1.0 mg/ml, concentration activity Av=1.0 MBq/ml; pH
2.7±0.3.
Table 3. The results of radiometric measurements and calculation of tungsten sorption on acidic and neutral
alumina

AVequilibr, MBq/ml
Time,
hours
1
2
3
6
12
24

Al2O3, pH 4.5
0,65
0,55
0,47
0,23
0,17
0,15

Al2O3, pH 7.0
0,96
0,90
0,84
0,67
0,63
0,62

Static sorption capacity,
mg of W/ g of sorbent
Al2O3, pH 4.5
Al2O3, pH 7.0
35
4
46
11
54
17
78
33
84
37
86
39

If follows from the data given in the Table that the sorption of tungsten (85.0 mg/g) at pH 4.5 of thesorbent is twice as much as that at pH 7.0 of the sorbent (38.0 mg/g). Time for reaching theequilibrium state is more than 12 hours.
The study of 188W in dynamic adsorption
Dynamic adsorption of 188W was performed directly on the generator’s column by passing theworking solution though a layer of theadsorbent.
The working solutions were sterilized
when they were passed through thesterilizing filter for microfiltration –“Sartorius”. The dimensions of thegenerator’s glass column were as
follows:  = 15 mm, L = 85 mm.
Acid Al2O3 was used as an adsorbent.
Experiments on W dynamic sorption
on acid aluminum oxide (pH 4.5
Fluka), sorbent weight – 1.0g, were
done
forsubstantiating
and
188
188
developing
W/ Re generator
Fig.1. Dynamic sorption capacity as a function of theloading procedure. The working
amount of W passed through the chromatographic column.
solution was passed through thechromatographic column using aperistaltic pump at the rate of 1 ml/min. The activities were measured by the gamma-spectrometricmethod. The results are given in Figure 1 and Table 4.
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Table 4. The amount of W adsorbed on Al2O3 column (1.0 mg) and the amount of W in the tail solution as afunction of the amount of W delivered for loading

N
os
.
1
2
3
4

Breakthroughof W to thetail, %
3,30
3,30
3,10
8,60

1
2
2,8
10,33

Amount of W
delivered forloading, mg
30
60
90
120

W adsorbedon the column,
mg
29,00
58,00
87,20
109,67

96,70
96,70
96,90
91,40

5

15,20

22,81

150

127,19

84,80

6

24,80

44,6

180

135,40

75,20

7
8
9

32,70
38,60
43,50

68,6
92,6
117,6

210
240
270

141,40147,40152,40

67,30
61,40
56,50

10
11
12
13
14
15

48,40
52,30
55,65
59,10
61,90
64,40

145,26
172,6
200,3
230,2
259,9
289,9

300
330
360
390
420
450

154,74
157,40159,68
159,68160,10160,10

51,60
47,70
44,35
40,90
38,10
35,60

W in the tail,mg

W adsorbed on
the column, %It follows from the results given that the maximum dynamic sorption capacity of aluminum oxide is
160 mg W/g. The optimal dynamic sorption capacity (DSC) of aluminum oxide is 100 mg W/gbecause the integral sorption is 97% in this case. If a solution continues to be passed through thecolumn, sorption percentage will be lower at a higher value of DSC.
Elution curve
Having the generators loaded, an elution curve
was plotted for each generator by passing afixed amount of NaCl isotonic solution by
portions of 1.0 ml. The concentration activityof Rhenium-188 was measured in each portionof the eluate. Fig. 2 shows the elution curve of
200 mCi 188W/188Re generator as an example.
It follows from Fig.2 that 5ml of the eluate
contains more than 80% of Rhenium-188.
Optimalparameters
procedureoftechnologicalFig.2. 188Re elution curve from 200 mCi 188W/188Re
generator.

The development of Rhenium-188 generator
loading technology was carried out using sorption columns with different quantities of aluminumoxide of “Fluka” or “Merck” trademarks. A shielding lead case was used as radiation shield of thesorption column. Specific activity of tungsten-188 raw material (Technical Specifications 7011025-20553876-2003) was from 2Ci/g to 7 Ci/g.
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The main optimal parameters of loading of 188W/188Re generator with the activity of up to 1Ci havebeen ascertained on the basis of the results presented and the experiments, which had been done
earlier [1-4]:








adsorbent – acid alumina (for example, Al2O3, pH 4.5, Fluka; Al2O3, pH 4.0, Merck);
dynamic sorption capacity 100 mg of W/ g of sorbent;loading solution flow rate 1.0 ml/min;tungsten concentration 1.0 mg W/ml;
pH of the loading solution within the range of 2–3;
volume of the loading solution 0.5–1.0 L;
loading time 0.5 – 3.0 hours.

Loading of generators of various activities
It has been found as a result of the studies on loading of Rhenium-188 generators of various
activities that the process optimal parameters are as follows (see Table 5):
Table 5. The optimal parameters of the process of 188W/188Re generator loading
Activity ofAmount of theFlow rate of the loading Eluent volume, ml
generator, mCi
adsorbent, gsolution, ml/min
100 - 200
3.0
1.0 – 3.0
5 – 10300 – 1000
5.0 – 6.0
1.0
10 – 15
Quality control
The eluates produced from Rhenium-188 generators were subject to quality control. `All theparameters regulated by State Pharmacopoeia in relation to radiopharmaceuticals were controlled.
The applied methods of the analytical control are listed in Table 6.
Table 6. Analytical control methods

Parameter
Radioactive concentration
Tungsten concentration
pH
Concentration of chloride-ionsChemical purity
Radiochemical purity

Analysis method
Gamma-spectrometry (GAMMA 1P)
Spectrophotometry (SF-56)
Potentiometry (“I-130” ion-meter)
Argentometry, titration (“I-130” ion-meter)
Atom-emission spectroscopy, spectrophotometry
Paper electrophoresis

It has been found out that rhenium-188 yield from 188W/188Re generator is not less than 85 %;chemical impurity concentration (Al, Fe) is not more than 5.0 g/ml; 188W content in the eluate is
not more than 110-3 % 188Re activity; the other radionuclide impurities content is also not morethan 110-3 % of 188Re activity; radiochemical purity of sodium perrhenate, 188Re is not less than
99.8%.
CONCLUSION
The production technology of a chromatographic 100 – 1000 mCi 188W/188Re generator has beendeveloped and mastered.
The quality of 188W/188Re generator was competitive with the best foreign analogs: rhenium-188
yield from 188W/188Re generator is not less than 85 %; chemical impurity concentration (Al, Fe) is
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not more than 5.0 g/ml; 188W content in the eluate is not more than 110-3 %radiochemical purity is not less than 99.8%.

188

Re activity;

The SSC RF–IPPE produces tungsten-188 /carrier free rhenium - 188 generators on a routine basis(TS 9452-031-08624390-2006). Registration certificate FS 02032006/5395-06 “Article of medical
equipment - Rhenium-188 generator GREN-1”.
About 50 generators in the activity range of 100 – 1000 mCi for Russian and foreign clinicalhospitals have been produced since 2004 till the present day.
REFERENCES
1. Semenova A.A., Stepchenkov D.V., Baranov N.G., Sokolov A.B. XVII Mendeleev Congress on
General and Applied Chemistry, 2003, Kazan, 2, 415.
2. Sharkova O.V., Stepchenkov D.V., Semenova A.A., Baranov N.G., Sulim E.V., Petriev V.M.,
Skvortsov V.G. All-Russian conference “Modern problems of nuclear medicine andradiopharmaceutics”, 2002, Obninsk, 15.
3. Baranov N., Stepchenkov D., Nerozin N., Zinchenko M., Semenova A., Minko Yu., Sulim
E., Poddubienko V, Petriev V. European Association of Nuclear Medicine Congress, 2006,
Athens, 417.
4. Stepchenkov D.V., Baranov N.G., Sharkova O.V., Semenova A.A., Sulim E.V., Nerozin N.A.,
Poddubienko V.P., Minko Yu.V. The Fifth Russian Conference on Radiochemistry, 2006,
Dubna, 228.

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4.13.
SUBSTANTIATION OF ENGINEERING PARAMETERS OF RHENIUM-188
STATIONARY GENERATOR INTENDED FOR RADIONUCLIDE
THERAPY
Baranov N.G., Stepchenkov D.V., Nerozin N.A., Sulim E.V., Yu.V.Minko, Semenova A.A.
Federal State Unitary Enterprise “State Scientific Center of the Russian Federation –Institute for Physics and Power Engineering”,
Bondarenko sq., 1, Obninsk, Kaluga region, 249033, Russia

Keywords: nuclear medicine, chromatographic generator, radionuclide therapy, dynamic
sorption, yield of Re-188 radiunuclide into eluate.
Abstract:
Re-188 generators producing eluates of about 100-500mCi/ml concentration activity are currently
in demand in the world nuclear medicine. One of the methods of this problem solving is thedevelopment of Re-188 stationary generator. Production technology of 1Ci 188W/188Re generator
GREN-1 based on 188 W sorption on aluminum oxide in chromatographic column in acid form is thebasis of the development. Research results of the choice of effective sorbent, determination of thesorbent optimal granulometric composition, sorbent sorption capacity and rate of initial solution
flow through the column, study of the influence of W-188 mother radionuclide specific activity on
the eluate concentration activity are presented. Calculation substantiation of shielding material andits size providing the radiation safety during generator operation is presented. It has been
established that during the operation of 188 Re generator of up to 5 Ci activity it is possible obtain in
fractional elution a sodium perrhenate solution of up to 500 mCi/ml regulated concentration
activity.
Introduction
Available separating methods of the mother (W-188) and daughter (Re-188) isotopes can be used in
the development of Re-188 generator: distillation, chromatography, extraction. Taking into accountthe experience of the adsorption-type 99Mo/99mTc generator operation the research was directed on a
study of sorption properties of materials applied in 99Mo/99mTc generator system. Silica gel,aluminum oxide (in acid, neutral and alkaline forms), zirconium oxide, yttrium oxide, and tin oxide
were researched under static conditions. Aluminum oxide is acid form was studied under dynamic
conditions. Isotonic solution of sodium chloride only was used for Re-188 radionuclide desorption.
Experiment
Solution of sodium tungstate in sodium hydroxide solution “Sodium tungstate (Na2WO4), 188W” of
74-171 GBq/g specific activity in W-188 was used as initial raw radioactive material (Table 1). The
product is produced by irradiation of tungsten trioxide WO3 in high-flux reactor SM-3 with neutron
flux density 2 1019 m-2 s-1 (JSC “SSC RIAR”, Dimitrovgrad).

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Table 1. Characteristics of W-188/Re-188 generator system

Daughter radionuclide
Isotop Decay Energy ande,
type
intensity,
Т1/2
MeV
188
Re 
 2.12 max
16.9h
e- 0.081,
0.143
 0.155(15%)

Parent radionuclide
Isotope, Decay Energy and
Т1/2
type
intensity,
MeV
188
W

 0.349 max
69.4day 0.227s(0.22%);
0.291 (0.4%)

Productio
n method186

W(n,)W(n,)
188
W
187

Eluent5, 10, 15 ml
0.9 % NaCl

Semi-conducting spectrometer of gamma-radiation energy “Gamma-1P” and dose-calibrator“Atomlab 100 plus” were used for radiometric control of solutions under investigation. Eluate
radiochemical purity was determined by the methods of electrophoresis and ascending
chromatography. Hydrogen ion activity in solutions was determined by potentiometric method withthe use of ion meter I-130m and pH-tester “Checker”. Sodium chloride concentration in eluate wasdetermined by argentometric method. Chemical element concentration was controlled with the helpof spectrometric analysis methods. Sorbent granulometric composition was determined by screen
grate “Analysette 3” made by PRO Fritsch. “BINDER GmbH Postfach 102” sterilizer was used.
Results and discussion
When studying sorption of tungsten compositions in static mode the metal oxides (yttrium,
zirconium, tin, aluminum) were used. Seed size was 100-30mkm, proportion of sorbent weight andinitial solution volume was 1:50, and nanostructured aerogel was Al2O3·Н2О. It has been
established that aluminum oxide in Н+-form is the most effective sorbent (Table 2). It follows fromthe Table 2 that the tungsten sorbtion by aluminum oxide with pH 4.5 almost twice exceeds thevalue for sorbent with pH 7.0 within equilibration time 12 hours.
Table 2. Study of 188W adsorption in static mode

Time, hour
1
2
3
6
12
24

Static sorption capacity, mg W/g of sorbent
Al2O3, pH 4.5
35
46
54
78
84
86

Al2O3, pH 7.0
4
11
17
33
37
39

Optimal technological parameters of chromatographic generator have been studied in dynamic
mode on the columns of different geometrical dimensions with the use of aluminum oxide in Н+
form of definite granulometric composition. Solution of sodium tungstate of 1-10GBq/ml
concentration activity and 0.50 – 10 mg of W/ml concentration was used as radioactive solution(Fig.1). It has been established that working solution for tungsten composition sorption should havethe optimal concentration 5.5 mg of W/ml. When studying the influence of solution pH on thetungsten sorption properties the initial raw material with pH 12-13 was adjusted to the needed pH
value with the help of titrated 1M, 0.01M solutions of hydrochloric acid, to needed tungstate-ion
concentration – by addition of water for injections and 0.001 M solution of hydrochloric acid. It has
been stated that solution pH in the range of 2.0 –3.0 corresponds to the optimal value (Fig. 2).

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Fig.1. Spectra of solution for loading

Fig. 2 Influence of solution pH on tungsten
sorption properties.

Sorption column was filled with 3.0-19.0 g of pH 4.5 aluminum oxide with seed size in the range of
0.25 – 0.063 mm having uniform granulometric composition. Rate of pH 2.0 – 3.0 solution flow
was varied from 0.65 to 4.0 ml/min. The column was washed with 200 ml sodium chloride solution.
Elution was performed every 3 – 4 days after the generator loading.
Based on a set of experiments carried out the main optimal parameters of 188W/188Re generator
loading of up to 1 Ci activity have been established (Table 3), which are the basis for thedevelopment of 188W/188Re generator of 5 Ci activity [1, 2].
Table 3. 188 Re generator loading optimal parameters

Activity ofgenerator, GBq

Sorbent weight, g

2.4-7.4
11.1-37.0
185

3.0
5.0 – 6.0
20.0 – 50.0

Solution flow rate
through thecolumn, ml/min
11
1–3

Eluent volume, ml
5 – 1015
5 – 50Experiments on a model facility have been carried out to substantiate 185 GBq 188Re generator
loading technology: sodium tungstate solution concentration activity – 18.5 MBq/ml, tungstate-ion
concentration – 5.5 mg/ml in terms oftungsten, pH of loading solution – 3,
the initial solution volume – 1.0 L,
solution flow rate – 1.5 ml/min, loading
duration – 10 hours, sorbent –aluminum oxide in Н+ -form, sorbent
weight – 54.18 g, sorbent seed size –0.16 – 0.10 mm. It has been stated thatthe maximal dynamic sorption capacityof this sorbent is 160.1 mg of W/gsorbent, optimal sorption capacity is
100 mg of W/g. In this case the integral
sorption is 97 % (fig. 3). When solution
further flows through the column at
Fig.3. Dynamic sorption capacity (mg W/g) as a function ofhigher DSC value the sorption
W amount passed through the chromatographic column.
percentage is less (Table 4). With full
elutionvolume(50ml)
the
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concentration activity is 0.3 MBq/ml (fig. 4, 5). In this case rhenium yield is 85% of 188W activity.
During successive elution by portions: 30 ml - the concentration activity increases up to 0.5
MBq/ml; 15 ml – the concentration activity increases to 1.3M Gb/ml. Thus, the eluates of different
concentration activity up to 11.1 GBq/ml and more can be obtained in fractional elution.

Fig. 4. Spectra of solution of eluate from 188W/188Re Fig 5. Elution curve of Re-188 radionuclide fromstationary 188W/188Re generator.
generator

Table 4. Results of calculation of tungsten weight sorbed on aluminum oxide pH 4.5

Weight of tungstate-ion in terms of tungsten, g
#
1
2
3
4

1
2
2.8
10.33

Broughtonsorption column
30
60
90
120

5

22.81

150

127.19

84.80

6
7
8

44.6
68.6
92.6

180
210
240

135.40141.40147.40

75.20
67.30
61.40

9

117.6

270

152.40

56.50

10
11
12
13
14
15

145.26
172.6
200.3
230.2
259.9
289.9

300
330
360
390
420
450

154.74
157.40159.68159.68160.10160.10

51.60
47.70
44.35
40.90
38.10
35.60

In tail solution

Sorbedaluminum oxide
29.00
58.00
87.20
109.67

Tungsten sorption
on value , %
96.70
96.70
96.90
91.40

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Calculation of the maximal and minimal exposure rates on the surface of 188 Re generator
shielding container has been carried out in order to estimate the properties of the shield structure
designed (radiation source activity was 24 GBq in 188W). Calculation has shown that 188Re
radiation gives practically all contribution to the dose rate around the source and insignificant
contribution is from 188W. This is connected with the fact that 188W emits photons of less than 0.35
MeV energy, for which the optical thickness of the lead shield exceeds 30 free paths, and therefore
it is completely shielded. Calculation results obtained are in agreement with the experimental dataand present a spatial exposure rate distribution in the neighborhood of 188Re generator container.
Conclusion
188

Re stationary generator design and technology have been developed on the basis of thetechnology of 188W/188Re chromatographic generator of 2.4 to 3.7 GBq activity [3, 4]. It has been
established that the eluate from 188W/188Re generator contains 80 – 90 % of 188Re, chemical
impurity concentration (Al, Fe, W, etc.) is at the level 0.005-5.0mkg/ml, 188W concentration is at thelevel 10-3 %, the other gamma-emitters are totally not more than 10-3 % of 188Re activity,
radiochemical purity of sodium perrehenate, 188Re, is not less than 99.0% [2]. Stationary 188 Re
generator of 185 GBq activity allows obtain sodium perrehenate solution of different volume with
controlled concentration activity up to 500 mCi/ml. It is a promising way of commercialization of
the technology developed. This allows enlarge the range of radiopharmaceuticals synthesized,
reduce the cost of patient treatment and increase the efficiency of treatment of socially importantdiseases.
References
1. Baranov N.G., Stepchenkov D.V., Petriev V.M., et al. Proceedings of the Annual Congress ofEuropean Nuclear Medicine Association EANM06, September 30 – October 4, 2006, Athens,
Greece, p.156.
2. Stepchenkov D.V., Baranov N.G., Sharkova O.V., et al. “Radiochemistry-2006”, Dubna, 338.
3. Registration certificate FC 02032006/5395-06. 188W/188Re generator for the right of its
production as medical equipment.
4. Re-188 generator GREN-1. TS 9452-031-08624390.

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4.14.
MATHEMATICAL MODELS FOR PHARMACOKINETICS AND
DOSIMETRY IN EXPERIMENTAL RADIOBIOLOGICAL STUDIES OF
BONE-SEEKING RADIOPHARMACEUTICALS 188Re-KHEDP
A.N.Klyopov1, V.M.Petriev2, V.G.Skvortsov2, V.A.Sokolov2,
V.V.Kanygin3, V.K.Shiryaeva2, O.P.Aleksandrova2
1

Obninsk Institute for Nuclear Power Engineering of National Research Nuclear University, Obninsk, Russia
2
Medical Radiological Research Centre of the Ministry of Health and Social Developmentof the Russian Federation, Obninsk, Russia
3“MEDRADIOPREPAPAT”, Federal Medical and Biological Agency, Moscow, Russia

Keywords: radiopharmaceutical 188Re-KNEDP, pharmacokinetics, dosimetry, mathematicalmodelsAbstract
The purpose of work was to model pharmacokinetics of radiopharmaceutical 188Re-KHEDP
and calculate the absorbed doses (AD) in critical organs of laboratory animals according toexperimental radiobiological studies. Multi-chamber model of 188Re-KHEDP metabolism in rats
was developed. The received results are intended for the further application of data in clinicalpractice.
Materials and methods
The study the pharmacokinetics of mono potassium-hydroxyethylidene-1 ,1-diphosphonicacid (KHEDP) salt was carried out on white rats, females with an average weight of 175 g.
Altogether 24 animals. Bone pathology was simulated by fractured right femur. Manipulation of theanimals were under ether anesthesia. Over the next 14 days, callus was formed, which served as amodel of bone disease. 0.2 ml of 188Re-KHEDP were injected into the tail vein . In 1, 3, 5, 24, 48
and 72 hours after the injection groups of 4 animals in each time period were decapitated, isolatedorgans and tissue samples were weighed and measured for radionuclide content by direct
radiometry. According to radiometric counting the content throughout the body was estimated inpercentage of the injected amount.
With the purpose of definition of the adequate scheme of radiopharmaceuticalpharmacokinetics various variants compartment models were involved. As a result space-temporaldependences of radiopharmaceutical accumulation-withdrawal has been realized on the basis ofmodel with 40 chambers. Transport of 188Re-KHEDP metabolites in extracellular space of organs ofa rat was considered. As a whole the model included 62 kinetic parameters (constants of aninterchamber exchange) which were defined by a method of numerical identification. Calculation of
the absorbed doses was made following the MIRD methodology. Dose factors for organs of rats,
including critical bone structures, have been taken from [4, 5].
Mathematical modeling of 188Re-KHEDP metabolic processes needs to proceed a significant
volume of experimental data obtained in animals. Owing to diversity and individual manifestationsof interchamber communications initially it was not obvious what pharmacokinetic chamber model
can be effective. To determine the principal features of the pharmacokinetics of 188Re-KHEDP andsimplify identification of kinetic parameters it was developed multi-chamber scheme. It was
assumed that the main features of the metabolic process will then be truly "caught up" with the next
"fractional" multi-chamber models.

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Table 1. Distribution of 188Re-KHEDP in organs and tissues of rats after intravenous administration (%dose/organ)№ Organ, tissue

Time after administration (%dose/organ)
5 min

1h

3h

24 h

48 h

72 h

1 Blood8,60±0,76
3,40±0,37 2,20±0,56 0,43±0,14 0,40±0,07 0,81±0,22
2 Thyroid
0,019±0,003 0,057±0,010 0,085±0,020 0,010±0,003 0,004±0,001 0,016±0,002
3 Lungs
0,17±0,01 0,072±0,02 0,043±0,003 0,011±0,001 0,006±0,002 0,004±0,001
4 Liver
2,40±0,11
1,20±0,05 0,90±0,10 0,41±0,02 0,33±0,02 0,067±0,023
5 Kidneys
2,19±0,12
2,06±0,16 1,71±0,10 0,70±0,02 0,41±0,02 0,26±0,04
6 Heart
0,14±0,02 0,051±0,005 0,024±0,002 0,012±0,001 0,003±0,001 0,009±0,004
7 Spleen
0,13±0,01 0,090±0,010 0,060±0,006 0,034±0,006 0,027±0,005 0,014±0,006
8 Stomach
0,31±0,03
0,17±0,02 0,18±0,02 0,043±0,005 0,028±0,003 0,023±0,008
9 Intestines
1,15±0,15
0,65±0,10 0,60±0,07 0,13±0,02 0,079±0,024 0,24±0,06
10 Muscle
9,25±1,25
2,69±0,62 0,95±0,14 0,87±0,20 0,73±0,04 0,77±0,22
11 Joint
0,94±0,10
1,19±0,06 1,03±0,03 0,71±0,04 0,70±0,06 0,55±0,08
12 Thigh bone
0,52±0,06
0,53±0,04 0,52±0,02 0,39±0,02 0,40±0,04 0,32±0,07
Thigh bone13
1,27±0,22
1,23±0,17 1,07±0,19 0,82±0,11 0,86±0,03 0,52±0,08with a fracture
14 Shin bone
0,15±0,02
0,16±0,01 0,12±0,01 0,13±0,01 0,11±0,02 0,081±0,019
15 Skull bone
2,55±0,28
2,59±0,12 2,33±0,15 1,76±0,12 1,49±0,126 1,47±0,19
16 Rib Bone0,63±0,06 0,59±0,084 0,57±0,14 0,41±0,01 0,41±0,04 0,35±0,05
17 Vertebrae bone 6,73±0,82
6,89±0,35 5,97±0,23 3,97±0,31 4,18±0,18 3,12±0,30
We would like to note that using a basic scheme of traditional multi-chamber schemes ofchamber models in the form [1] proved to be ineffective. As a result of significant number of tests a
reasonable option of the multi-model was offered.

Fig. 1. Compartmental model for 188Re-КOEDF metabolism.

This option is displayed in the block diagram (Figure 1), and includes a system of equationsfor kinetics of the corresponding substrates of 188Re:
blood chamber («BLOOD») – compartaments "1" and "10":
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011dq1
 (a61  a81  a71   ð )  q1  a16  q6 ;dt

dq10
 (a8,10   ð )  q10  a10,6  q6
dt

soft tissue chamber («SOFT») – compartaments "2" and "6":dq6dq10
 (a26  a16   ð )  q6  a61  q1  a62  q2 ; (a62   ð )  q2  a26  q6
dt
dt
bone tissue chamber (“BONE”) compartaments "3" and "7”:dq7dq3
 (a37  a47   ð )  q7  a71  q1;
 (a37   ð )  q3  a37  q7
dt
dt
kidney chamber («KIDNEY») – compartaments "4" and "8":dq8dq4
 (a98   ð )  q8  a8,10  q10  a81  q1;
 (a54   ð )  q4  a47  q7
dt
dt
urine chamber («URINE») – compartaments "5" and "9",

(1),

(2),

(3),

(4)

where λp  the decay constant of 188Re, aij – coefficients of inter-chamber communications. The
initial conditions: q1(0) = 1; i1(0) = 0; i. > 1. The "camera" here refers to the combined organs,bodies and tissues, "compartament” – their metabolically different subsystems.
Figures 2-5 show the kinetics of the recovered activity of the 188Re-KHEDF and its
metabolites in chambers «BONE», «BLOOD», «SOFT», «KIDNEY», «URINE», as a fraction of
the injected activity and decay of 188Re.

Fig. 2. Kinetics of 188Re - activity in boneFig. 3. Kinetics of 188Re - activity in blood

Fig. 4. Kinetics of 188Re - activity in soft tissues

Fig. 5. Kinetics of 188Re - activity in urine

Absorbed doses (AD) in the critical organs were calculated according to MIRD
recommendations [2],
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R

DT  A0   q~S , r  Sr (T  S ) ,r 1

where qS,r – the resident time for 188Re in the source-organ (r); Sr (T – S) – S-factor [2].
Resident time for the bladder was calculated taking into account its periodic emptying. The
cycle time emptying was taken as 0.5 hours. S-factors for the case of 188Re in relation to a numberof critical soft tissues and organs were taken from [3,4]. S-factors for series of energies ofmonoenergetic electrons and γ-rays have been calculated in [5]. It must be emphasized that in [5]they were obtained for the case of a homogeneous distribution of the nuclides in terms of bone
(trabecular and compact). They can be used as lower estimate for "true" values of S-factors, since
the volume-distribution of radiopharmaceuticals in the bone are certainly less than S-factors of
surface-tropic ones by a larger absorption in the volume of bone. Since the bone structure of rats,
especially trabeculae bone, are quite small, the resulting estimates of factors for the absorption ofrelatively hard β-radiation 188Re, does not seem to be strongly distorted in comparison with the"true". The results of calculations of the specific AD are listed in Tables 3, 4.
Table 2. The specific partial and total absorbed doses of 188Re-KHEDP in rats
AD perorgan,
Gy/Bk

Contribution in dose: S·Ã [mGy/Bk]

BladderHeart
KidneyLiver
Lungs
SpleenStomachSkeleton

Bladder
1,162E04
3,504E10
1,243E09
9,732E10
3,667E10
1,032E09
9,117E10
8,426E09Heart
9,879E12
1,133E06
3,166E11
3,239E09
4,885E08
2,587E11
9,282E11
1,654E09

Kidney9,489E10
2,024E09
4,090E05
1,703E07
2,699E09
7,527E07
3,073E07
1,443E08

Liver
5,114E10
1,007E07
9,653E08
6,475E06
4,863E07
1,637E09
2,866E07
2,278E08

Lungs
7,713E12
7,021E08
7,872E11
2,058E08
7,846E07
5,904E11
1,125E08
1,646E08

Spleen3,586E11
8,943E11
3,042E08
1,374E10
9,371E11
7,232E06
4,142E08
5,349E10

Stomach7,251E11
4,368E10
2,893E08
4,689E08
4,213E08
9,202E08
3,679E06
5,970E09SI
6,134E08
2,239E10
5,965E08
1,727E08
2,540E10
5,400E08
2,747E08
6,040E07

Skeleton
6,657E1,163E-07
08
9,526E2,259E-09
07
1,696E4,129E-08
07
3,789E7,114E-09
07
6,454E7,819E-09
06
1,211E8,254E-09
07
5,998E4,954E-09
07
3,120E1,449E-09
08

Table 3. Absorbed 188Re-КHEDP doses in bone marrow of rats

Specific absorbed doses, Gy/BkБк

Vertebraebone
1,83 E-007

Femur bone

Skull bone Shin bone

4,1 E-008

7,8 E-009

1,4 E-008

Refrences
1. Savio E., Gaudiano J., Robles A.M., Balter H., and et. al. Re-HEDP: pharmacokinetic
characterization, clinical and dosimetric evaluation in osseous metastatic patients with twolevels of radiopharmaceutical dose. BMC Nuclear Medicine, 2001, 1:2.
2. Bolch W. E., Eckerman K. F., Sgouros G., and Thomas S. R. MIRD pamphlet No. 21: A
generalized schema for radiopharmaceutical dosimetry—Standardization of nomenclature. J.
Nucl. Med., 2009, Vol. 50, p. 477-484.
3. Stabin M.G., Peterson T.E., Holburn G.E., and Emmons M.A. Voxel-Based Mouse and Rat
Models for Internal Dose Calculations. J. Nucl. Med., 2006; Vol. 47: p. 655–659.

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4. Peixoto P.H.R., Vieira J.W., Yoriyaz H. and Lima F.R.A. Photon and electron absorbed
fractions calculated from a new tomographic rat model. Phys. Med. Biol. 2008, Vol. 53: p.
5343–5355.
5. Xie T., Han D., Liu Y., Sun W., and Liua Q. Skeletal dosimetry in a voxel-based rat
phantom for internal exposures to photons and electrons. Med. Phys., 2010, Vol. 37, No. 5:
p. 2167-2178.

N. S. Al-Hokbani, N.N. Popova, G. L. Bykov, M.S. Grigoriev

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4.P1.
THE GENERATOR 99mTс BASED ON INORGANICSORBENT “TERMOKSID-5”
N.D. Betenekov, E.I. Denisov, L.M. Sharygin*, M.N. Golubev
UrFU, Ekaterinburg, ndbetenekov@dpt.ustu.ru*Closed joint-stock company RPF TERMOXID, Zarechny, Russia

The eluted activity from a technetium generator will contain small amounts of avariety of impurities. The nature of these impurities and their concentration is important.
The following should be considered when preparing 99mTc radiopharmaceuticals. This end
use places a stringent requirement on the various types of purity of the product. Productpurity may be considered to consist of radionuclide impurity, radiochemical purity,
chemical purity and biological purity. There are however contaminants that are inherent in
the 99Mo on to the generator column and that may be released from the alumina column
during elution. Since these components are frequently present, their allowable
concentrations may be defined and quality control tests for their presence and concentration
may be applied. The following components contribute to the suitability of the eluted 99mTc:
Al+3 ion end activity99Mo.
It is impossible to completely eliminate all aluminum ions. Recommended limits for
Al+3 (United Stated Pharmacopoeia [USP] for example) are 10 µg / mL when the column isprepared from fission molybdenum and 20 µg / mL when thermal neutron activation is used
to prepare the 99Mo.
There are varying regulations concerning the allowable levels of 99Mo in the eluted
product or in the radiopharmaceuticals prepared for human administration. A generally
accepted requirement (United States Pharmacopoeia) is that the final radiopharmaceutical
will not contain more than 0,15 KBq of 99Mo per MBq of 99mTc at the time ofadministration.
The chemical composition of thermostable inorganic sorbent “Termoksid-5” (T-5) isa mixture of oxides titanium and zirconium. It has high molybdenum selectivity, radiation
resistant and chemically stable.
The generator 99mTc (based on the brand sorbent T-5) can be produced for bigger
activity at smaller sizes of the sorption column. Model experiments of the separation 99Mo
and 99mTc showed satisfactory results: 0,90 ± 0,05 technetium and less than 10-5 ofmolybdenum transfer to isotonic solution after multiple elution (more accurate results canbe obtained at higher specific activity of the molybdenum).

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4.P2.
INVESTIGATION OF THE SORBENTS ON THE BASIS OF THE NEWPHOSPHORYL-CONTAINING LIGANDS FOR ALLOCATION,
CONCENTRATION AND PURIFICATION OF THE MOLYBDENIUM
FROM THE IRRADIATED URANIUM TARGETS
Baulin V.Е.1,3, Kovalenko O.V.1, Usolkin A.N.2, Voroshilov Y.A.2,
Yakovlev N.G.2, Tsivadze A.Yu.1
1

A.N.Frumkin Institute of physical chemistry and electrochemistry RAS, Moscow, Russia mager1988@gmail.com
2
Federal State Unitary Enterprise "Production Association" Mayak ",Ozersk, Chelyabinsk region,
3
Institute of Physiologically Active Compounds of the RAS, Chernogolovka, Moscow Region

The 99Mo is a precursor of 99mTc applied for diagnostics in the nuclear medicine. Oneof the main methods for 99Мо-99mТс production is the U irradiation in the reactor, 99Мо
being produced due to 235U fission with the yield of approximately 6%. Preparative
chromatography with use of highly effective sorbents (PZC or Thermoxid) is promising
separation method of allocation, concentration and purification of 99Mo from accompanying
collateral elements. A new kind of chelating polymeric adsorption materials weredeveloped and synthesized by non-сovalent fastening of the new ligands (I) into the pores(40-250 µm) of polymeric (styrene-divinylbenzene) particles to separate effectively_of_Mo
from solutions, obtained by dissolution of the irradiated uranium targets in HNO3. The
adsorption of some typically simulated elements Мо, Тc, U, Th, Np, Pu towards adsorbent
was investigated by examining__the inﬂuence of the structure of phosphoryl-containing
ligands, their percentage contents in an adsorbent, contact
Otime, concentration of HNO3 and presence of the stripping
Phagents in the solutions. It was found that a number of thePO
investigated materials exhibited excellent selectivity forPh99
Mo overall of the tested elements. The optimumO
conditions
for effective adsorption and stripping of these
R1
P
elements have been determined. The dynamic distribution
R R
factors were high resulting in quantitative purification ofI99
Mo from accompanying collateral elements in demi99
R=Ph, p-Tol, OEt, OH, R 1=H, n-Alk industrial pilot scale. The technique for Мо determinationin the irradiated uranium targets was proposed. The
obtained data testify the new adsorbents potential for radiochemical manufacturing of 99Mo99m
Tc generators.
The work was supported by RFBR (grant № 11-03-00509-а)

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4.P3.
NOVEL TECHNETIUM AND RHENIUM COMPLEXES WITH THE NHETEROCYCLIC ALDEHYDE THIOSEMICARBAZONES - POTENTIAL
RADIOPHARMACEUTICALS
L. Fuks*, E. Gniazdowska, P. Kozminski, J. Mieczkowski 1
Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw, Poland
1
Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland* e-mail: leon.ichtj@gmail.com

Keywords: technetium-99m, radiopharmaceuticals, thiosemicarbazones, complexes,
radiolabelling
Abstract

Pyridine- or quinolinecarboxaldehyde thiosemicarbazones and technetium form compounds inwhich the ligand is bound di- or tridentately. Because the ligand may exist as neutral molecule ofthe thiourea origin or as the monohydric acid anion coming from the thioenol form, properties ofthe metal complex strongly depend on the conditions of the synthesis. The aim of presented work is
to check, if labelling the N-heterocyclic aldehyde thiosemicarbazones with tricarbonyl [99mTc]technetium(I) may lead to formation of the complexes suitable for the radiopharmaceutical
purposes. Syntheses of the complexes were provided in the conditions analogous to those at present
performed in the nuclear medicine laboratories. Main physicochemical properties of the complexes
were studied. Semiempirical geometry optimization and energy of the compounds calculation werealso performed using the MPW1PW functional or the DPCM (Dielectric Polarizable Continuum
Model), respectively, implemented in Gaussian 98.
Introduction

In the attempt to develop novel 99mTc-complexes potential radiopharmaceuticals, our interest has been
linking to the BM interaction
focused on the thiosemicarbazone (TSC) chelators.
Inspection of the literature on the TSC complexes withdifferent metals has shown that the compounds may be
accounted as prospective pharmaceuticals, because they
32
1 NH NH R
may bind with a great number of biological targets, e.g.
N2'bacteria, fungi and viruses [1], parasites [2], tumorousSN
tissue [3]. They may also serve as the anti-inflammatory
agents [4]. TSC ligands are capable of metal cometal chelation andordination in different modes [5] and the complexes arehydrogen bonding area
stable enough to be a source of these thiourea
Fig 1. Complexing sites of substituted
derivatives. Conjugated N,N,S donor atoms of thethiosemicarbazide
thiosemicarbazide (NH2-CS-NH-NH2) moiety together
with the Ri substituent (of the parent aldehyde / ketone
origin) form potentially tridentate ligands which alone also exhibit the desired biological activities[6,7].
hydrophobic pocket,

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Radiolabeled thiosemicarbazones have been used for treatment of different diseases and/or in
medicinal diagnosis for over three decades. Apart from Tc-99m, radionuclides tested up-today
were: Cu-62, Cu-64 and Cu-67, Ga-67 and Ga-68, Pd-103 and nonmetallic I-125 1.
Within our interest on the technetium and rhenium complexes for biomedical applications, we haverecently started the synthesis and characterization of their complexes formed with threepyridinecarboxaldehyde and two quinolinecarboxaldehyde thiosemicarbazones. In spite of the factthat both metals in the complexes may exist in one from the nine oxidation states ranging from -1 to+7, only four of them (+7, +5, +3 or +1) appear in the compounds used in the medicinal sciences.
2-pyridinecarboxaldehyde thiosemicarbazone Detailed intent of the presented
3-pyridinecarboxaldehyde thiosemicarbazone studies, performed within this more
N NH
N
NH2
4-pyridinecarboxaldehyde thiosemicarbazone general project devoted to theS
comparisonofthecomplexN
2-quinolinecarbaldehyde
thiosemicarbazone
formation, stability and basic
N NH
NH2
properties of the aforementioned
S
ligands labeled with Tc/Re in the +5
and +1 oxidation states, is to present
results obtained for the tricarbonylNcation 99mTc(CO)3+ complexed with
4-quinolinecarbaldehyde thiosemicarbazone
N NH
the 2-quinolinecarbaldehyde thioseNH2
S
micarbazone (Q2TSC).

Experimental

Synthesisof
2-quinolinecarbaldehyde
thiosemicarbazone (Q2TSC): this ligand was obtained by
N
N
O
N NH
reaction of 0.1 mol of 2-quinolinecarboxaldehyde
NHS(dissolved in 100 mL of an ethanol-water, 1:1, and 5
mL of conc. HCl) with 0.12 mol of thethiosemicarbazide (in 10 mL of ethanol). After stirring for 2 hrs at RT followed by heating under
the reflux for 2 hrs, crude thisemicarbazide (yellow or orange) in hydrochloride form has been
filtered out and recrystallized from ethanol. Thiosemicarbazide hydrochloride dissolved in 200 mLof hot water was slowly neutralized with aq. solution of 10% Na2CO3. Crude thiosemicarbazide inneutral form was crystallized from ethanol. Yield:  90 %.
Synthesis of the 99mTcI(CO)3-Q2TSC complex: For
N
N
N
N
Tc(CO) (H O)NN
the labeling with Tc-99m, a kit containing 5.5 mg
SNS
65 C; 30 min
N
Tc
NaBH4, 4 mg Na2CO3 and 10 mg Na-K tartarate,COCO
purged with CO gas prior to addition of Na99mTcO4, asCO
described elsewhere [8]. Then, 1 mL of an aqueous
99m+
mixture of [ Tc(OH2)3(CO)3] (~ 0.5 GBq/ml) and the TSC ligand (6.5·10-4 M) at pH 9.5, reacted
at 65 oC for 30 min. The reaction mixture was analyzed by RP HPLC to estimate the yield and thecomplex was purified by isolating the radioactive peak from the column. The reaction yield was ca
95%.
Radiochemical purity of the 99mTc-TSC complex was determined by paper chromatography using
acetone as the developer.
All ligands were characterized by C, H, N and S analyses, IR and 1H NMR spectroscopy.
Analytical HPLC was run on a SUPELCOSIL C-18 (Supelco) column (particle size: 5 µm, L = 25cm; φ = 10 mm); flow rate of 1mL/min; radiometric and UV detection (254 nm); eluents: A - 0.01
M phosphate buffer (TEAP) pH = 7.4, B - MeOH; method: 0-3 min - 100%A; 3-6 min - 100%A 
H2N NH
S

NH2

2

3

2

+

o

+

1

See, webpage http://inisdb.iaea.org/

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75% A; 6-9 min - 75%A  66% A; 9-20 min - 66%  0%A; 20-25 min - 0%A; 25-30 min - 0% 
100%A; 30-35 min - 100%A.
Lipophilicity determination: logPo/w values of the 99mTc-complexes were determined by multiple
extraction in the n-octanol/PBS system (pH 7.40), which mimics the physiological conditions(ambient temperature; -radiation counting) [9]. After separation the phases, aqueous solutions wereanalyzed by the RP-HPLC to check whether the complexes studied had not decomposed during theexperiments.
Paper electrophoresis experiments were performed in the phosphate buffer (0.1 M, pH 7.40). The
analyses were carried out for 60 min at 200 V. After drying the paper strips, distribution of theradioactivity along the strips was determined by the -radiation counting.
Computational details: As in our previous studies [10], structure optimization (DFT, B3LYP
model; 6+311G** basis) and energetic calculations (Dielectric Polarizable Continuum Model,
DPCM) were performed using the Gaussian 98 programme.
Results and Discussion.

The fac-[99mTc(CO)3]+ moiety is nonpolar, has an almost spheric shape, and offers up to 3 sites onan octahedral face for ligand attachment.
800
All TSCs studied can be effectively radiolabeled with 99mTc(CO)3+
18.4
under mild conditions (30 min at 65 oC, pH=9.5, 30 min, 5·10-4 M
TSC) to form well-defined complexes with a high enough yield.
400
Generally, HPLC analyses of the ligands as well as of the complexes
19.0
18.2
show two / three clearly resolved peaks. Results obtained for the
0
18
19
20
complexes formed by the pyridinecarboxaldehyde ligands (viz., thet, minP2TSC, P3TSC and P4TSC) are published elsewhere [11].
In the presented paper we present results obtained for 2Fig. 2. HPLC
quinolinecarbaldehyde thiosemicarbazone (Q2TSC). In the ligand, 2chromatogram of Q2TSC
quinoline and thiourea groups can be syn (Z) or anti (E) with respect
21.2
the central C2'-C1 and C1=N1 bonds, where C2' stands for carbon
atom in the 2-quinoline moiety (for numbering of the atoms, see
5000
Tc(CO) L
21.7
Scheme in the Introduction). Therefore, rotations around these bonds
22.8
2500
result in a change of the ligand's conformation. Performed calculationshows, that relative values of the energy of three main isomers 0
15
20
25
30
t (min)(Z,Z), (E,E) and (Z,E) - are0, 2.45 and 5.65 kcal/mole, respectively. HPLC retention times forFig. 3. Radio-HPLC
these isomers are 18.2, 18.4 and 19.0 min (assignment of thechromatogram ofrespective isomers has not been done
tricarbonyl complexesyet) and for the complexes - 21.2, 21.7
suggested
Catode (-)
Anode (+)
and 22.8 min. All complexes wereisolated by HPLC their lipophilicity assigned as the logP determinedin the standard conditions. Respective values are: 1.02, 0.54 and 1.69.
These values are significantly greater than these obtained for thepyridinecarboxaldehyde complexes [11].
Charges of the complexes were determined by the paper
Fig. 4.
electrophoresis. Slightly positive values suggest that the tricarbonyl
Electrophoregram ofcomplexes are of the [99mTc(CO)3LN,N,S]+ composition and are formed[99mTc(CO)3LN,N,S] +by involving three donor atoms of the ligand as shown in the scheme
presented in the Introduction. Thioketo form of the ligand is involved in complex formation.
Separated HPLC fractions of the complex were buffered to pH 7.40 and tested for their stability
both in the pure buffer or in the histidine and cysteine challenge experiments. Results obtained
show that it is not sufficiently stable to be taken into account as the radiopharmaceuticals’
precursor.
N

N NH

NH2

A.u.

S

N

N NH

NH2

cpm

S

3

Q-2

800

cpm

600

400

Tc(CO)3(Q2)

+

200

TcO4

0

25

50

75

100

125

-

150 175

200

mm

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The work is in progress.
Conclusions.

Positively charged complex of [99mTcI]-tricarbonyl complex with 2-quinoline carboxaldehyde
thiosemicarbazone: (a) exists in the form of three isomers of medium lipophilicity, (b) is notresistant to re-oxidation even for the relatively short time, and (c) shows also small resistance in thestandard challenge experiments. As a result, contrary to the pyridinecarboxaldehyde
thiosemicarbazone complexes [11], it may not be considered promising candidate for theradiopharmaceutical precursor.
Acknowledgments: The work is carried out within the grant of Polish Ministry of Science andHigher Education No N N204 141437. We acknowledge Prof. N. Sadlej-Sosnowska (National
Institute of Drugs, Warsaw) for calculations, which were carried out in the Interdisciplinary Centre
for Mathematical and Computational Modeling of Warsaw University.
References.

1.
2.

3.

4.
5.
6.
7.
8.
9.
10.

11.

e.g. G. Pelosi, F. Bisceglie, F. Bignami, P. Ronzi, P. Schiavone, M.C. Re, C. Casoli, E. Pilotti,
J. Med. Chem., 53, 8765-8769 (2010).
e.g. (a) R. Pingaew, S Prachayasittikul, S Ruchirawat, Molecules 15, 988-996 (2010); (b) C.L.
Donnici, M.H. Araújo, H.S. Oliveira, D.R.M. Moreira, V.R.A. Pereira, M. de Assis Souza,
M.C.A. Brelaz de Castro, A.C. Lima Leit, Bioorg. Med. Chem., 17, 5038-5043 (2009); (c)Cerecetto, H.; M. Gonzalez, Mini Rev. Med. Chem., 8, 1355-1383 (2008).
e.g. (a) Z. Afrasiabi, E. Sinn, S. Padhye, S. Dutta, S. Padhye, C. Newton, C.E. Anson, A.K.
Powell, J. Inorg. Biochem., 95 306-314 (2003); (b) L.A. Saryan, E. Ankel, C. Krishnamurti,
D.H. Petering, H. Elford, J. Med. Chem., 22 1218-1221 (1979).
e.g. K. Raman, H.K. Singh, S.K. Salzman, S.S. Parmar, J. Pharm. Sci., 82, 167-169 (1993).
T.S. Lobana, R. Sharma, G. Bawa, S. Khanna, Coord. Chem. Rev. 253 977-1055z (2009).
X. Du, C. Guo, E. Hansall, J. Med. Chem. 45, 2695-2707 (2002).
D.B. Lovejoy, D.R. Richardson, Blood 100, 666-676 (2002).
R. Alberto, R. Schibli, A. Egli, P.A. Schubiger, J. Am. Chem. Soc. 120, 7987-7988 (1998).
Product Properties Test Guidelines OPPTS 830.7550, US Environmental Protection Agency,
1996.
(a) L. Fuks, E. Gniazdowska, N. Sadlej-Sosnowska, Struct. Chem. 21, 827-835 (2010); (b) L.
Fuks, N. Sadlej-Sosnowska, K. Samochocka, W. Starosta, J. Mol. Struct. 740, 229-235(2005).
L. Fuks, E. Gniazdowska, P. Kozminski, J. Mieczkowski, J. Radioanal. Nucl. Chem. DOI
10.1007/s10967-011-1404-4.

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4.P4.
99m

Tc-LABELLED VASOPRESSIN ANALOGUE
d(CH2)5[D-Tyr(Et2),Ile4,Eda9]AVP AS A POTENTIAL
RADIOPHARMACEUTICAL FOR SMALL-CELL LUNG CANCER (SCLC)IMAGING
Ewa Gniazdowskaa,*, Przemysław Koźmińskia, Krzysztof Bańkowskib,aInstitute of Nuclear Chemistry and Technology, Warsaw, Polandb
Pharmaceutical Research Institute, Warsaw, Poland* e-mail: e.gniazdowska@ichtj.waw.pl

Keywords: technetium-99m, radiolabelling, radiopharmaceuticals, vasopressin, receptor
Abstract
The 99mTc-labelled conjugate of vasopressin peptide analogue d(CH2)5[D-Tyr(Et2)-Ile49
Eda ]AVP has been synthesized using the technetium complexes with tetradentate tripodal chelator– the tris(2-mercaptoethyl)-amine, and monodentate isocyanide ligand. The conjugate exhibits highstability in the presence of excess of standard amino acid cysteine or histidine, and satisfactorystability in human serum. The novel vasopressin peptide conjugate can be considered promising
diagnostic radiopharmaceutical for patients suffering from small-cell lung cancer (SCLC).
Introduction
The aim of the work was to synthesize and investigate the conjugate of the d(CH2)5[DTyr(Et2),Ile4,Eda9]AVP peptide, the analogue of vasopressin, with the mixed-ligands “4+1”technetium(III) complex.
Vasopressin (arginine vasopressin, (Arg8)-Vasopressin, AVP) is a cyclic peptide (disulfide
bond between Cys1 and Cys6) containing nine amino acid residue (Cys1-Tyr2-Phe3-Gln4-Asn5-Cys6Pro7-Arg8-Gly9). AVP is a peptide hormone found in most mammals, including humans. AVP
regulates body retention of water, being released when the body is dehydrated (antiduretic action of
AVP, mediated via V2 type receptors). In addition to its predominantly antidiuretic and bloodpressure activities, vasopressin demonstrates a variety of neurological effects on central nervous
system (CNS). It is involved, via different receptor subtypes, in higher brain functions, including
cognitive abilities and emotionality. In the recent years, interest increased in the role of vasopressinin its participation in such diseases as schizophrenia and autism [1]. The half-live of the vasopressin
peptide in vivo is about 15-20 min [2]. The overexpression of vasopressin receptor V2 has beenfound on small-cell lung cancer (SCLC) [3-5]. Physicochemical properties of the 99mTc-labelledvasopressin peptide were already studied [6].
The AVP analogue, d(CH2)5[D-Tyr(Et2)-Ile4-Eda9]AVP, AVP(an), is one of the several
effective antagonists (Fig. 1A) of the antidiuretic (V2-receptor) responses to arginine vasopressin
[7].
A

O

N
H
N
O

O
N
H

H
N
O

O

H
N

N
H

O

O

B

O

H
N

N
H

S
N

S

N

S

R

N

O

O

NH 2

N

N

M
S

peptideC
NSO

M=99mTc, Re

Figure 1.
Tyr(Et2)-Ile4-Eda9]AVP, (AVP(an))99m(B) - Tc labelled peptides using the “4+1” approach;(A) - d(CH2)5[D-

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The “4+1” mixed-ligand technetium complex consists of central metal ion Tc(III) coordinatedby a tetradentate NS3 tripodal chelator tris(2-mercaptoethyl)-amine and a monodentate isocyanide
ligand previously coupled with the selected biomolecule (Fig. 1B). The identity of the 99mTclabelled AVP(an) was corroborated by investigation of an analogous rhenium compound.
Experimental
The analogue d(CH2)5[D-Tyr(Et2)-Ile4-Eda9]AVP, AVP(an), was a gift from Professor
Maurice Manning, University of Toledo, Toledo, Ohio, United States.
The compounds: tetradentate NS3 ligand (tris(2-mercaptoethyl)-amine; 2,2’,2’’nitrilotriethanethiol, R=H), aliphatic linker CN-BFCA (BFCA = Bifunctional Coupling Agent) monodentate isocyanide ligand (isocyanobutyric succinimidyl ester), CN-AVP(an) - the isocyanide
linker CN-BFCA coupled with AVP(an) and the “cold rhenium precursor” Re(NS3)(PMe2Ph)
were synthesized according to the procedures described in Refs. [6,8-11].
MS of CN-AVP(an), (m/z): Calcd: 1231.61, Found: 638.8 [M+H]+
Re(NS3)(CN-(AVP(an)): MS (m/z): Calcd: 1612.1, Found: 829 [M+H]+
The 99mTc-labelled AVP(an) conjugate wasformed in two-step synthesis, via the 99mTc-EDTA
intermediate complex [6,8,9,11], with the final yield of
95%.
Results and Discussion.

99m

Tc(NS3)(CN-AVP(an))
labeling mixture,  detection

The HPLC chromatograms of the compounds
Re(NS3)(CN-AVP(an)),
RT=15.9
min,
and
99m
Tc(NS3)(CN-AVP(an)), RT=16.3, min are shown in
Figure 2.

99m
Tc(NS3)(CN-AVP(an))
purified,  detection

99m

Figure 2. The HPLC chromatograms of the
Tc/Recomplexes prepared in this study (Phenomenex JupiterProteo analytical column, 4 μm, 90 Å, 250  4,6 mm,
under condition: solvent A-water with 0.1 % TFA(v/v), solvent B-acetonitrile with 0.1 % TFA (v/v),
gradient elution: 0-20 min: 20 to 80 % solvent B, 10
min-80 % solvent B; 1 ml/min, -detection.)

Re(NS3)(CN-AVP(an))
UV-Vis detection, 220 nm
0

0

5

10

15

20

25

30

min

Figure 2. The HPLC chromatograms of the99m
Tc/Re complexes prepared in this study(Phenomenex Jupiter Proteo analyticalcolumn, 4 μm, 90 Å, 250  4,6 mm, undercondition: solvent A-water with 0.1 % TFA(v/v), solvent B-acetonitrile with 0.1 % TFA(v/v), gradient elution: 0-20 min: 20 to 80 %solvent B, 10 min-80 % solvent B; 1 ml/min,-detection.)

The log D value of -0.44 ± 0.03 for the 99mTclabelled AVP(an) was found (the value may becorrected by introduction a hydrophilic group, R, at
the periphery of the NS3 ligand).
The conjugate 99mTc(NS3)(CN-AVP(an)) exhibits highstability. Figure 3 shows the percentage of intact
conjugate in the challenge experiments with an excess(10 mM) of histidine or cysteine during incubation of the isolated conjugate at 37oC. After 24 h ofincubation the obtained HPLC chromatograms have shown the existence of one radioactive species
in the solution, of the retention time characteristic for the complex studied.

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Tc(NS3)(CN-AVP(an))

100

75

99m

50

% of intact

in 10 mM histidine solution25

in 10 mM cysteine solution

0
0

4

8

12

16

20

24

time of incubation [h]Figure 3. Histidine and cysteine challenge experiments: thepercentage of intact 99mTc(NS3)(CN-AVP(an)) complex
remaining after various incubation times at 37 oC

cpm

cpm

The
HPLC
chromatograms
obtainedafter
incubationof
99m
Tc(NS3)(CN-AVP(an)) conjugate inhuman or rat serum are shown in
Figure 4. The conjugate studied is also
very stable in human and rat serum, on
the contrary to the 99mTc-labelledarginine vasopressin peptide. The
biomolecule AVP(an), the antagonistof the V2 vasopressin receptor, does
notundergothe
enzymatic
biodegradation in vivo, even in rat
serum.

after 15 min of incubation

after 15 min of incubation

after 90 min of incubation

after 90 min of incubation
0

0

0

5

10

15

min

20

25

0

5

10

15

20

25

min

Figure 4. HPLC chromatograms of 99mTc(NS3)(CN-AVP(an)) conjugate after incubation at 37 oC in human(left) and rat (right) serum (analyses carried out under the conditions described above)

Conclusions.
In conclusion, one can say that the novel conjugate of the vasopressin peptide analogued(CH2)5[D-Tyr(Et2),Ile4,Eda9]AVP with the “4+1” mixed-ligands technetium(III) complex can beconsidered promising diagnostic radiopharmaceutical for patients suffering from small-cell lungcancer (SCLC).
Acknowledgments:
The work was carried out in part as the statutory work of the Institute of Nuclear Chemistry andTechnology and within the grant No: N R13 0150 10 (Polish Ministry of Science and Higher
Education).
References.
1. E. Frank and R. Landgraf, Best Pracice & Research Clinical Anaesthesiology, 22, p. 265-273(2008).
2. A. C. Guyton and J. E. Hall, Text Book of Medical Physiology, 10th edition, Saunders W. B.,
Philadelphia PA., 2000.
3. C. Pequeux, C. Breton, J.-C. Hendrick, M.-T., H. Martens, R. Winkler, J.-J. Legros, Cancer
Research, 62, 4623–4629, 15 (2002).
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4. W. G. North, M. J. Fay, K. A. Longo, Jiniin Du, Cancer Research, 58. 1866-1871. I. (1998).
5. C. Pequeux, B. P. Keegan, M.-T. Hagelstein, V. Geenen, J.-J. Legros, W. G. North, EndocrineRelated Cancer, 11, 871–885 (2004).
6. E. Gniazdowska, P. Kozminski, K. Bankowski, H.-J. Pietzsch, Annual Report INCT, 77-81(2008).
7. M. Manning, J. Przybylski, Z. Grzonka, E. Nawrocka, B. Lammek, A. Misicka and Ling Ling
Cheng, J. Med. Chem., 35, 3895-3904 (1992) and references cited therein
8. S. Seifert, J.-U. Kuenstler , E. Schiller, H.-J. Pietzsch, B. Pawelke, R. Bergmann, H. Spies,
Bioconjugate Chem. 15, 856-863 (2004).
9. J.-U. Kunstler, G. Seidel, R. Bergmann, E. Gniazdowska, M. Walther, E. Schiller, C.
Decristoforo, H. Stephan, R. Haubner, J. Steinbach, H.-J. Pietzsch, J. Med. Chem., 45, 36453655 (2010).
10. H. Spies, M. Glaser, H.-J. Pietzsch, F. E. Hahn, T. Luegger, Inorg. Chim. Acta 240, 465 478(1995).
11. J.-U. Kuenstler, B. Veerenda, S. D. Figueroa, G. L. Sieckman, T. L. Rold, T. J. Hoffman, C. J.
Smith, H.-J. Pietzsch, Bioconjugate Chem. 18, 1651-1661, (2007).

Ya. Zubavichus, O. Bozhkov, L. Borisova and Ch. Tsvetkova

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4.P5.
COMPLEXES OF TECHNETIUM-99m AND RHENIUM-188 WITHZOLEDRONIC ACID IN NUCLEAR MEDICINE
A.O. Malysheva, G.E. Kodina, O.E. Klementyeva.

Burnasyan Federal Medical Biophysical Center FMBA Russia (Zhivopisnaya st. 46, Moscow, Russian Federation)

Keywords: bone metastases, diagnosis, technetium-99m, therapy, rhenium-188, zoledronic acid
Abstract:
99m

Tc and 188Re represent an attractive pair of radionuclides for biomedical use because of theirfavorable decay properties for diagnosis (99mTc) and therapy (188Re) and because of their onsite
availability, thanks to corresponding generator systems. Furthermore, the elements technetium andrhenium reveal similar chemical properties. This circumstance offers the possibility tosimultaneously develop diagnostic and therapeutic tracers with almost identical chemical andpharmacokinetic characteristics. Diphosphonic acid derivatives labeled with 99mTc have been
widely used as imaging agents for bone diseases. Diphosphonates labeled with 188Re may be used
for treatment of bone metastases. Zolidronic acid (ZA) was chosen as the object for investigation
due to it therapeutic effect and accumulation in the bone metastases. The skeletal uptake of 99mTcZA was about 50 %, the uptake ratio of bone-to-muscle was more than 50 at 1 h after injection.
Skeletal uptake of 188Re-ZA was 20.0 % and 14.2 % after 1 and 3 h post injection respectively.
Introduction

Bone metastasis is a major complication of several solid cancers: the prostate, breast, lung, kidney,
and thyroid are cancers most associated with bone pain (most often, breast and prostate). Althoughbone metastases are often clinically silent, they can lead to serious sequelae, such as pain, fractures,and hypercalcemia. These complications often reduce performance status and decrease the quality oflife. Bone pain due to metastasis is often considered a unique type of pain. It is initially a dull or
aching pain, worse at night that improves with physical activity [1]. Skeletal metastases areclinically significant because of associated symptoms, complications such as pathological fracture
and their profound significance for staging, treatment and prognosis. Detection of bone metastases
is, thus, an important part of treatment planning.
Bisphosphonates are an important class of osteotropic compounds that are effective in treating
benign and malignant skeletal diseases characterized by enhanced osteoclast-mediated bone
resorption (i.e., osteoporosis, Paget’s disease, and tumor-induced osteolysis). The evolution ofbisphosphonates has led to compounds with ever-increasing potency. First-generation
bisphosphonates, including etidronate and clodronate, contained simple side chains and wererelatively weak inhibitors of bone resorption. Second-generation compounds, including
pamidronate, alendronate, and ibandronate, have an aliphatic R2 side chain containing a single
nitrogen atom. These nitrogen-containing bisphosphonates (N-BPs) are up to 100-fold more potent
than the first-generation compounds. Zoledronic acid, a novel N-BP with an imidazole substituent,has demonstrated more potent inhibition of osteoclast-mediated bone resorption than all otherbisphosphonates in both in vitro and in vivo preclinical models. Recent data suggest that N-BPs
inhibit farnesyl diphosphate (FPP) synthase, an enzyme in the mevalonate biosynthetic pathwaythat is critical for protein prenylation and activation of important signaling molecules. Inhibition of
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FPP synthesis also leads to production of triphosphoric acid 1-adenosin-5′yl ester 3-[3-methylbut3-enyl] ester (ApppI), which induces apoptosis of osteoclasts and tumor cells. Our current
knowledge of the pharmacology of N-BPs at the molecular level largely explains their observed
effects on bone metabolism and tumor growth in animal models and their clinical activity in thetreatment of benign and malignant bone diseases.
99m
Tc-technetium (99mTc) and 188Re-rhenium (188Re) represent an attractive pair of radionuclides forbiomedical use because of their favorable decay properties for diagnosis (99mTc: 6 h half-life, 140keV γ-radiation) and therapy (188Re: 17 h half-life, 2.12-MeV β- max-radiation) and because of theironsite availability, thanks to corresponding 99Mo/99mTc- and 188W/188Re generator systems.
The aim of this study was to investigate the influence of reaction conditions such as pH,
concentration of SnCl2, concentration of the ligand (ZA), adding of carrier (in the case of 188Re),
time and temperature of reduction and etc. for the synthesis of 99mTc-ZA and 188Re-ZA complexes
and describe their biodistribution in experimental animals.
Experimental
Radionuclides and chemicals
Na99mTcO4 and Na188ReO4 were obtained from the domestic generators (both are produced by theInstitute of Physics and Power Ingineering, Obninsk, Russia). Zoledronic acid was synthesized in
Farm-Syntez Ltd. Russia; the other chemicals was commercially produced (Merck).
Preparation of 99mTc-ZA
5 ml of the Na99mTcO4 solution (5 - 20 MBq) was introduced into the vial with lyophilized mixtureof ZA (1.5 mg) and SnCl2 (0.3 mg). The radiopharmaceutical is ready to use after incubation atroom temperature for 20 min.
Preparation of 188Re-ZA
1,5 ml of the Na188ReO4 solution (750 – 2250 MBq) was added in the vial with lyophilized mixtureof ZA (4.0 mg), gentesic acid (2.3 mg), SnCl2 (1.5 mg) and Na188ReO4 (0.045 mg). The vail washeated on the boiling water bath during 30 min and then was cooled to room temperature. The
obtained solution was filtered via a Millipore filter 0.22 μ in the vial with 15 ml of physiologicalsolution.
Quality control
Radiochemical yields of 99mTc-ZA and 188Re-ZA, free pertechnetate or perrhenate and reducedhydrolyzed technetium or rhenium were determined by silica gel TLC (Merck 5553/acetone) andpaper chromatography (Whatman 3MM/0.9 % saline).
Experimental animals and biodistribution
All animal experiments followed the principles of laboratory animal care. Female white rats about
200 g body weight with and without bone pathology. Experimental anumals were housed underconditions of controlled temperature (26 °C), humidity (68%) and daily light cycle (12 h light/12 hdark). The bone pathology was simulated by the closed femur fracture. Biodistribution of both
radiopharmaceutical compositions were studied in with bone pathology in 10 days post-fracture
model. About 0.2 mCi of 99mTc-ZA or 188Re-ZA was injected intravenously into each of the rats via
the tail veins. At the indicated points in time (1 and 3 h) the animals were sacrificed and dissected.
The selected tissues were removed and the radioactivity was counted by a γ-counter to determine
tissue distribution of the radiotracers. In vivo biodistribution studies were performed in triplicate foreach radiotracer and time point. The results were tabulated as percentage of the injected dose pergram of tissue (% ID/g), using reference counts from a definite sample of the initial injected. The
radioactivity of the sample and standards was measured by use of a γ-counter (Wizard 2480-0010,
PerkinElmer LAS /Wallac).
Results and Discussion.
Search of the optimal reagent composition «Rezoskan,99mTc» was carried out in the following
range: zoledronic acid 0.2 – 0.9 mg/ml, SnCl2 0.02 – 0.08 mg/ml. The results of this search are
shown on Fig, 1 – 4. It was found that radiopharmaceutical composition of 99mTc-ZA with
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radiochemical purity > 95 % can be prepared using ligand:SnCl2 molar ration from 2.5 to 3.5 at pH
5.0 – 6.5 after incubation for 20 min at room temperature.
98

100 RCP

RCP

98
96

96
94

94
93
92

94

92

SnCl2, mg/ml

92
90

90
3,5

4,5

5,5

рН 6,5

Fig. 1. Dependence of RCP from pH
of radiopharmaceutical composition
98
97
96
95
94
93

0

ZA, m g/m l

0,2

0,05

0,7

1,2

Fig. 2. Dependence of RCP from
Fig. 3. Dependence of
RCP from concentration of
SnCl2 concentration
zoledronic acid

RCP

ZA, m g/m l

Search of the optimal reagent composition “Zoleren,
Re” was carried out in the following range: zoledronic
acid 1.5 – 2.6 mg/ml; SnCl2 0.5 – 2.5 mg/ml; gentesic
acid 0 – 4.5 mg/ml; NaReO4 – 0 – 30 μg/ml (or 0 – 20
μg/ml Re). The results of this search are shown on Fig,
5 – 8. The described composition of 188Re-ZA can beprepared with radiochemical yield > 90 %. The
composition was stable during 3 h from the moment of it
preparation.
188

0

60

120 180 240 300
time, minFig. 4. Dependence of RCP from time
incubation of radiopharmaceuticalcomposition at room temperature
w ithout carrier

w ithout carrier

0,02 mg/ml Re

without carrier

ReO4, % 40
35

ReO4, %

30
25
20
15
10
5
0
0

0,5

1

1,5

2

2,5

concentration of SnCl2, mg/ml

w ithout carrie r

14
12
10
8
6
4
2
0
1,2

ReO4, %

100
90
80
70
60
50
40
30
20
10
0

14
12
10
8
6
4
2
0
0

1

2

3

4

5

concentration of gentesic acid, mg/ml

0

1

2

3

Fig. 2. Dependence of
RCP from concentration ofzoledronic acid

Fig. 3. Dependence of RCP fromconcentration of gentesic acid

0,02 m g/m l Re

16

1

0,02 mg/ml Re

0,02 mg/ml Re

concentration of zoledronic acid, mg/ml

Fig. 1. Dependence of RCP from
SnCl2 concentration
ReO4, %

RCP
96
95

1,4

1,6

pH

Fig. 4. Dependence of RCP from pH ofradiopharmaceutical composition

From our preliminary experiments it was found that pH of
the solution on the first step of preparation 188Re-ZA (duringrhenium reduction) should be quite acidic (pH < 1.5). The
yield of 188Re-ZA was decreased to 80 % at pH 2.5 - 3.5. We
also observed the influence of adding the carrier on the yieldof 188Re-ZA. Without the carrier the radiochemical yield was
also more than 90 %, but the composition was unstable.

Biodistribution of 99mTc-ZA and 188Re-ZA in vivo
The skeletal uptake of 99mTc-ZA was about 50 %, the uptake ratios of bone-to-blood were morethan 20 at 1 h and up to 100 at 5 h after injection respectively. Differential coefficient of uptake(CDU) femur-to-femur with pathology was between 1.7 to 2.1. The data of 99mTc-ZA
biodistribution are shown in Table 1. The pharmacokinetics of 99mTc-ZA in the bone pathology
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location is characterized by higher uptake and slow release in comparison with a normal bone tissue(Fig 9).
Table 1 Biodistribution of 99mTc-ZA in rats withmodel of bone pathology
Organ/Tissue
Blood, %ID/g
Liver
Kidneys
Bladder
Femur normal
Femur with bone injury
Sceleton

Fig 9. Pharmacokinetics of 99mTc-ZA in
rat’s bones

СDU

1 h p.i.
2.04  0.81
1.71  0.58
1.82  0.83
35.11  10.53
2.13  0.20
4.21  1.04
57.70  5.54
2.0

3 h p.i.
1.72  0.71
1.13  0.42
1.44  0.68
44.81  3.89
1.92  0.42
4.03  1.34
46.62  7.81
2.1

Since the use of 99mTc-ZA expected in patients receiving therapeutic dose of zoledronic acid, we
studied the effect of this therapy on the quality of SPECT imaging of bone pathology. Experiments
were carried out in rats with a bone pathology model, which simulated a fractured right femur.
Seven days after fracture the animals were intravenously injected a solution of zoledronic acid in
0.9% saline at the dose of 0.04 mg per rat. The obtained data are shown in Table 2. The data of
188
Re-ZA biodistribution are also shown in Table 2.
Table 2. Biodistribution of 99mTc-ZA in animals after preliminary injection of zoledronic acid and 188ReZA (% ID)
99m
188
Organ/Tissue
Tc-ZA
Re-ZA

The
obta
ined
data
sug
gest
Femur with bone injury
2,57 ± 0,83
2,37 ± 0,48
3.96  0.60
3.70  0.03
that
Sceleton
31,96 ± 2,75
38,29 ± 5,47
55.62  7.70
51.40  6.89
the
СDU
2.0
2.4
2.2
1,7
use
of therapeutic drugs based on zoledronic acid does not cause an overflow of the exchange of bonepool and therefore will not have a significant impact on the quality of the SPECT imaging of theskeleton lesions with 99mTc. 188Re-ZA rapidly accumulates and securely fixed in both normal femur
bone and in bone pathology.
Blood, %ID/g
Liver
Kidneys
StomachFemur normal

1 h p.i.
0.18  0,06
1.71  0,54
1.55  0,13
0.31  0,02
2.02  0,20

3 h p.i.
0.03  0.01
0.62  0.04
1.14  0.34
0.48  0.30
1.98  0.26

1 h p.i.
0,43 ± 0,17
0,25 ± 0,05
3,19 ± 1,02
0,18 ± 0,01
1,16 ± 0,31

3 h p.i.
0,17 ± 0,07
0,14 ± 0,03
3,85 ±1,26
0,21 ± 0,11
1,39 ± 0,68

Conclusions.
The possibility of simultaneous development of diagnostic and therapeutic radiopharmaceuticals on
one chemical base with almost identical chemical and pharmacokinetic characteristics is shown.
The optimal conditions for preparation of lyophilized reagent and RPhs “Rezoskan,99mTc” and“Zoleren,188Re” were found. Nowadays “Rezoskan,99mTc” is allowed for clinical usage. The
preclinical trials of “Zoleren,188Re” will be finished in 2011.
Acknowledgments: The work was supported by “Farm-Sintez” Ltd., Moscow, Russia.
References.
A Casciato DA, Chansky HA. Bone and joint complications. In: Casiato DA, Lowitz BB, eds.
Manual of Clinical Oncology. 4th ed. Philadelphia, PA: Lippincott Williams Wilkins; 2000: pp.
601–614.
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4.P6.
PRODUCTION OF 188W AND EXTRACTION OF 188RE AT IRT-T
V.G. Merkulov, E.V. Chibisov, V.V. Zukau, Yu.S. Maslennikov,
G.G. Glukhov
Physical-technical Institute of Tomsk Polytechnic University
Tomsk, 634050, Russia, 30, Lenin Avenue, lab31radcontrol@rambler.ru

Every year about 480 thousand cases of malignant neoplasmas are diagnosed in Russia. The
morbidity has increased by 16% for the past 10 years. Nowadays more than 2.5million patients areregistered on the books in oncological medical facilities, it’s 1.8% of the country population.
From the view point of effective medical care 188Re radioisotope is considered the mostperspective radionuclide for application of its compounds in beta-rays therapy of malignant
neoplasmas, bony metastasis, rheumatoid arthritis and other diseases by open radionuclide sources.
Radioisotope of 188Re (Т1/2=16,98 h) is received as a daughter product at beta decay of 188W
(Т1/2= 69,4 days), which in its turn is produced in the reaction (n;γ) of the second order in nuclear
reactors by irradiating tungsten oxide of the natural isotopic composition (28,64 % 186W), or byconcentrating 186W isotope more than by 90%. The use of the cheap raw material as a starting target
results in further application of concentrating technologies for extraction of daughter radioisotope of
188
Re, the sublimation and extraction technologies are primary ones.
At nuclear reactor IRT-T of Physical-technical Institute of Tomsk Polytechnic University (themaximum flux of thermal neutrons is up to 1,5·1014 н·с-1·см-2) research works on production ofparent 188W and sublimation extraction of 188Re from the target of natural isotope compound werecarried out. Sublimation extraction of 188Re from irradiated targets of tungsten oxide (VI) was
carried out in the apparatus supplied with a refrigerated condenser, onto which Re precipitatedduring gaseous phase in the form of Re2O7. The research of 188Re extraction rate was studied in thetemperature mode of 600-7000С depending on the target mass and heating time. It is shown that thecontent of 188W in the fallout does not exceed 0,005% of the daughter isotope activity. The
percentage of molybdenum and antimony radio nuclides that are present in initial tungsten oxide(VI) as admixtures is less than the limits of detection. Radiochemical purity of the desired
preparation is more than 99%.
Thus, the experiments mentioned above create the preconditions for the development of theregional 188Re sublimation generator for providing medical facilities with 188Re based
radiopharmaceuticals.

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4.P7.
TC-99M GENERATOR PRODUCTION AND APPLICATION EXPERIENCE
Stepchenkov D.V., Nerozin N.A., Baranov N.G., Sulim E.V., Semenova A.A.
Federal State Unitary Enterprise “State Scientific Center of the Russian Federation –Institute for Physics and Power Engineering”,
Bondarenko sq., 1, Obninsk, Kaluga region, 249033, Russia

Key words: nuclear medicine, chromatographic Tc-99m generator, sorbent, eluate,radionuclide purity.
Abstract:
Results of scientific and production activities at SSC RF – IPPE in the field of manufacturingof Tc-99m generator, one of widely used in the world nuclear medicine are presented in the report.
Design and technological features of the short-lived isotope generator are presented. Ways of the
product quality improvement are considered.
Introduction
Improvement of SSC RF – IPPE production activity in the field of medical radioisotope
production is a strategic task of promotion of Russian nuclear medicine development. Since 1989
SSC RF – IPPE became one of developers and Russian producers of Tc-99m generators which is
widely used in nuclear medicine for diagnostics of different diseases of all essential human organs
and systems. The output volume of diagnostic radionuclide products based on eluate from Tc-99m
generator occupies the leading position in the world. More than 10000 diagnostic procedures withthe use of our 99Mo/99mTc generators are performed annually at 80 Russian hospitals. Distinguishedfeature of chromatographic Tc-99m generator produced at SSC RF – IPPE is the use of silica gel
modified by manganese dioxide and aluminum dioxide as sorbents. Within the 21-year of
production experience the quality parameters of the generator eluates produced have been brought
to a level of the best Russian and foreign patterns:
daughter radionuclide yield is not less than 80 %;radiochemical purity is not less than 99.8 %;concentration of radionuclide impurities is not morethan 10-3 % of Tc-99m activity; concentration of
stable impurities is not more than 5mkg/ml in total.
Operation experience and design characteristics ofgenerator have shown evidently their suitability,
reliability and safety of their application in clinicalpractice.
Tc-99m generator is designed in theform of compact facility providing radiation safety
and automatic elution mode with the use evacuatedvials.
Fig.1. Tc-99m generator view.
However, the most complicated and serious
quality problems of the sodium pertechnetateproduct remain the possibility of its contamination with sorbent material and radioactive impurities
of initial material due to radiation chemical processes and accumulation of water radiolysis
products.
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Work on the improvement of Tc-99m generators directed on the reduction of radionuclide andnon-active chemical impurities in eluate, refining of operation parameters, and radiation dose
reduction and work place is carried out at SSC RF – IPPE.
ExperimentSemi-conducting spectrometer of gamma-radiation energy “Gamma-1P” and dose-calibrator“Atomlab 100 plus” were used for radiometric control of solutions under investigation. Eluate
radiochemical purity was determined by the methods of electrophoresis and ascending
chromatography. Hydrogen ion activity in solutions was determined by potentiometric method withthe use of ion meter I-130m and pH-tester “Checker”. Sodium chloride concentration in eluate wasdetermined by argentometric method. Chemical element concentration was controlled with the helpof spectrometric analysis methods. Sorbent granulometric composition was determined by screen
grate “Analysette 3” made by PRO Fritsch. “BINDER GmbH Postfach 102” sterilizer was used.
Brief characteristics of 99Mo/99mTc generator system are presented in the Table 1.
Table 1. Characteristics of 99Mo/99mTc generator system

Daughter radionuclide
Isotope,Т1/2

Decay type

Energy andintensity, MeV

Tc
6.01h

Isomerictransition 0.140 (91%)
- 0.11999m

Parent radionuclide
Isotope,
Т1/2

99

Mo

66.02h

Decay
type

-

Energy andintensity, MeV

Production
method- 1.23 max
 0.181 (7%);
0.739 (12%);0.778 (4%)

235

U(n,f

)
99

Mo

Eluent

5ml
0.9 %
NaCl

Result and Discussion
During investigation of molybdate-ion dynamic sorption it has been stated that the maximal
sorption is possible when using sorbents in acid form and initial solutions possessing acid or neutral
medium (Table 2).
Table 2. Results of molybdate-ion (99Mo) sorption study with 100 mkg Mo/ml initial concentration
Adsorbent, weightрН of Mo-99
Adsorption on chromatographic column, %100mg
solution
After solution 1 After solution 2
After solution 3
passage (10 ml)
passage (10 ml)
passage (10 ml)
SiO2/MnO2 (neutral)
9.5
0
92
21
SiO2/MnO2 (neutral.)
6.4
43  529  317  3
SiO2/MnO2 (neutral.)2
54  535  533  5
MnO2 (кисл.)6.4
53  535  527  5
MnO2 (acid)2
64  753  550  5
Al2O3 (alkaline)
9.5
0
0
0
Al2O3 (neutral)
7.7
94.1  2.5
93.2  2.5
78.6  2.5
Al2O3 (neutral)
6.4
93.1  2.5
86.9  2.5
86.3  2.5
Al2O3 (neutral)
2
98.8  0.2
98.3  0.2
98.1  0.2
Al2O3 (acid)
6.4
99.9  0.1
99.9  0.1
99.9  0.1
Al2O3 (acid)2
99.9  0.1
99.9  0.1
99.9  0.1

To improve the eluate quality a composition of multilayer adsorbent has been suggested, oneof the layer of which contains silica gel modified with manganese (IV) dioxide in acid form, and theother layers are chromatographic aluminum oxide in acid, alkaline and neutral forms. Optimalengineering parameters of sorbent preparation have been developed: granulimetric composition,
control of critical processes and factors, generator loading technology with activity of 0.1 to 4.0Ci
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RF patented [1]. Investigations performed allow obtain eluates meeting the requirements of Russianand European Pharmacopoeia.
Russian Tc-99m generator is not worth than the foreign generators, its daughter radionuclide
yield is not less than 80% (fig.2). Currently Tc-99m generators are serially produced according tomodified technology meeting the requirements of quality assurance system – standards of ISO9001-2001.
3500Объемная активность, МБк/мл

Certified3000
production [2] of Tc99m generators a2500
system of quality
control has been
2000
developed and works
1500
at all process phases.
It includes an inlet
1000
control of initialmaterials and agents,
500
control of productsofauxiliary0
production, control
0
2
4
6
8
10
of
end
productОбъем элюата, млbatches within theservice life as well as Fig.2. Curve of Tc-99m elution by sodium chloride isotonic solution of 99Мо/99mТс
evaluationofgenerator of 11.1GBq activity
application quality of
Tc-99m generatorsdelivered to medical institutions [3].
Conclusion
A complex work on reconstruction of the medical production and its quality control is carriedout at SSC RF – IPPE in accordance with State Standard P 52249-2009 “Regulations of production
and quality control of medicines (GMP)”. Rearrangement of production and quality control systemallows provide the competitiveness of Tc-99m-generators at the world level and promote thedomestic product to foreign markets.
References
1. Patent of invention #2153357. Basmanov V.V., Sokolov A.B., Semenova A.A., et al.
“Generator for production of sterile radioproduct technecium-99m and method of its
preparation”. 2000.
2. License of the federal supervision service in the field of public health and social
development #99-03-001619 for the activity on medical equipment production at SSC RF –IPPE, 2009.
3. Registration certificate #FL 2008/03978 of 2008. Tc-99m generator GT-2M according to TS
9452-032-08624390-2008 giving the right to produce, sell and apply it in the territory of theRussian Federation.

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4.P8.
DETERMINATION OF ASCORBIC ACID IN KIT BY HIGHPERFORMANCE LIQUID CHROMATOGRAPHY
N.B. Epstein1, G.M. Khomushku1, L.D. Artamonova1, V.G. Skvortsov2
1

National Research Nuclear University MEPhI – IATE, Obninsk
2
Medical Radiological Research Center, Obninsk
NBEpshtejn@mephi.ru

Technetium-99m hydroxyethylidene diphosphonate (HEDP) and rhenium-188
hydroxyethylidene diphosphonate were developed at the MRRC for diagnose and treatmentof bone metastases, accordingly. The main quality control tests of radiopharmaceuticals
are: concentrations of HEDP, Sn(II), ascorbic acid, the percentage of 99mTc or 188Re
unbound with preparation (radiochemical impurity or RCI). In the present work, an HPLC
method for identification and quantification of AA in non-radioactive kit was developed.
Numerous analytical techniques have been proposed for its determination in different
matrices and at different levels. There is no information about AA determination inradiopharmaceutical kits. There are some difficulties in quantifying ascorbic acid in kits due
to simultaneous stannous ions presence and AA instability in aqueous solution. AA has
limited stability and may be lost from kits during preparation and storage. AA is readilyoxidized primarily to dehydroascorbic acid (DHA), which is a reversible reaction.
Generally, the total AA is defined as the sum of both AA and its oxidized form DHA. The
quantification of DHA is usually performed after its conversion into AA in the presence of
reducing agents.
The HPLC system (Shimadzu, SCL-10A), was equipped with UV detector system. The
LC-analyses were performed under isocratic mode at a flow rate 1 ml/min with detection at
265 nm. Sample and standard injections of 20 µl were made on a Supelcosil LC-18 column;
5 µm; 4.6250 mm; at 25 C. The separation was performed with a sodium acetate eluent(pH 5.4) containing decylamine as ion pairing agent. Standard solutions (AA and DHA) andsamples were prepared daily in volumetric amber glass flasks. Chromatographic peaks wereidentified by comparing its retention times with external standards. The experimental data
were analysed statistically to validate the proposed method.
AA was quantified in standard by means of an external calibration curve in theconcentration range 0.005 to 0.5 mg/ml. The HPLC method offers good accuracy andreproducibility, relative shot analysis time, unambiguous identification of AA in presence of
DHA. To prevent the loss of AA in the standard and the samples solutions, it was necessary
to prepare their with deaerated water and protect from light by using amber flasks. The
DHA was not quantified in AA standard and in samples. The presence of HEDP and Sn(II)in kit vial had no influence on the results of AA determination by HPLC.

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4.P9.
SYNTHESIS AND CHARACTERISATION COMPLEX OF THE{ReO}3+CORE WITH S/N AND N DONOR LIGANDS LIGANDS AND
OF ITS 99mTc ANALOG.
Noura Saad Al-Hokbany .
Department of chemistry, College of Science, King Saud University, Riyadh 11451, Kingdom of Saudi
Arabia. E-mail:nhokbany@ksu.edu.sa. Tel:+966 1 4772245; Fax: +966 1 4772245

Keywords: [ReO]3+, DFT, mercaptobenzothiazole ligand, Aminothazole ligand, 99mTc-gluconate,
B3LYP.
Abbreviations
Mer: mercaptobenzothiazole
Amino: Aminothiazole
ITLC: instant thin- layer chromatography.
SG-TLC: silica gel thin- layer chromatography.
HPLC: High performance liquid chromatography.
DFT: density function theory
Abstract
A novel mixed ligand 99mTc complex with mercaptobenzothiazole as ligand and Aminothiazole as
coligand was prepared and evaluated as potential brain radiopharmaceutical. Preparation at tracer
level was accomplished by substitution, using 99mTc-gluconate as precursor and a coligand/ ligand
ratio of 5. Under these conditions the labeling yield was over 97% and a major product withradiochemical purity >97% was isolated by HPLC methods and used for biological evaluation.
The reaction of [ReO(Citrate)2]- with mercaptobenzothiazole and Aminothiazole in hot MeOH
yields [ReO(mer)(amino)OH (H2O)2] . The DFT study demonstrated that the complex consists ofdistorted octahedral ReO(V). The coordination geometry at the rhenium is defined by a terminal
oxo-group, the nitrogen and sulfur donors of the chelating mercaptobenzothiazole, the nitrogen of
Aminothazole ligand, is present as deprotonated amido nitrogen.
Biodistribution in mice demonstrated early brain uptake, fast blood clearance and excretion throughhepatobiliary system. Although brain/blood ratio increased significantly with time, this novel 99mTc
complex did not exhibit ideal properties as brain perfusion radiopharmaceutical since brain uptake
was too low.

1. Introduction
The -emitting technetium-99m is the most widely applied radionuclide in diagnostic imaging.
Nevertheless, current research in radiopharmacology involves the exploitation of the coordination
chemistry of technetium as well as its congener rhenium to develop new radiotracers [1, 2]. In thepast decade, many efforts were focused on brain imaging technetium radiopharmaceuticals that may
cross the blood-brain barrier and localize in the brain. Although many of the Tc and Re complexes
have been investigated to date, clear structural criteria involved in brain uptake and retention oftechnetium complexes are not fully documented.
One of the important aspects in Tc radiotracer design is complex lipophilicity [3]. Since distribution
and passive transport through membranes are governed by lipophilicity, there is a considerable
interest in which way lipophilicity parameters can be controlled by chemical modifications at the
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tracer molecule. In this investigation on amine-bearing mixed-ligand rhenium complexes aims
toward this goal. These studies are triggered by the fact that the amine-carrying technetium species
are able to pass the intact blood-brain barrier and are accumulated in the brain [4, 5]. Keeping in
mind that rhenium complexes may serve as nonradioactive surrogates for their technetium
analogues due to similar molecular properties, the synthesis of Re (V) complexes requires thepresence of metal-containing chemical cores that are, stable enough to exist in aqueous solutionsand versatile enough to combine with the selected ligands. An example of such a core is the oxoform [ReVO]3+, in which the + 5 oxidation state of the metal is stabilized by the oxo-core [5,6].
The literature shows that a search for new radiopharmaceuticals requires studies of new oxorhenium(V) complexes with nitrogen and sulfur donor sets, as well as investigations of the chemical
behavior of their 99mTc analogs. In this work, we report the synthesis and characterization of a novel
complex of rhenium of the general type [ReO(mer)(amino)OH (H2O)2]. We have also studied theradiochemical properties of the corresponding technetium complex, which was prepared by two
methods.
Nowadays, ab intio computational techniques are a potent tool for research. Chemistry haschanged from a purely empirical science into a discipline in which deductive theory, as represented
by first-principles calculations using computers, is increasingly important for interpretation andguidance of experimental work. Recent developments in this area include the field of density
functional theory which meets with the requirements of being accurate. Currently density functional
theory (DFT) is commonly used for geometric optimization and electronic structure of transition
metal complexes. It meets the requirements of being accurate, easy to use and fast enough to allow
the study of relatively large molecules of transition metal complexes [7, 8]. Geometric optimizationand electronic structure of [ReO(mer)(amino)OH (H2O)2] has been determined on the basis of thedensity functional theory (DFT) calculations and additional information about binding has beenobtained by NBO analysis. The accuracy of the DFT calculations can be tested by comprising theavailable experimental data against calculation values. In our case study the experimental data
available will be the data gathered from spectroscopic measurements such as UV-Vis, FTIR and
NMR data.

2. Computational details
The GAUSSIAN 03program [9] (Gaussian 03 program) was used in the calculations. The complex
was treated as open shell-system and no symmetry constrains were applied. Geometrical
optimization of the investigated complex was carried out with Beck's three parameter exchange
functional B3LYP using the Los Alamos LANL2DZ spilt-valence basis set [10, 11]. A harmonic
vibrational analysis was performed following the geometrical optimization of the complex at thesame level of theory B3LYP and the same basis set [12]. An additional d function with exponent a= 0.3811 and an f function with exponent a = 2.033 on the rhenium atom were added [13]. Natural
bond orbital (NBO) calculations were performed with the NBO code [14] included in GAUSSIAN
03.
3. Experimental
3.1 Materials and methods
All the reagents used in the synthesis were commercially available and were used without further
purification. The ReO(citrate)2- precursor was prepared according to the literature [15] . IR wasrecorded on a Perkin Elmer spectrophotometer 1000 in the spectral range 200-4000 cm-1 withsample in the form of KBr pellets. Elemental analyses were performed on a Perkin-Elmer Analyzer
2400. 1H-13C NMR spectra were obtained in DMSO-D6 on JEOL NMR 400 MHz. Electronic
spectrum was measured on a UV-Vis Beckman Du-70 spectrophotometer in the range 190-700 nm
in aqueous medium.
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99m

TcO4- in saline solution was eluted from a 99Mo/99mTc generator obtained from Cis Bio
International Elumatic III, B.p.32. (France). Chemical reactions were monitored by thin- layer
chromatography on instant thin layer chromatography (ITLC, SG-TLC) using Whatman No.1
chromatography paper (Whatman International Ltd. UK) and Silica gel-60 F254 TLC- aluminium
sheets (Alltech). HPLC separations were carried out using a normal phase silica column (Econosil
10μm x 264 mm) using a dual pump (Jasco-pu-2089 plus Quaternary Gradient); methanol/
dichloromethane (1:1) was used as the mobile phase with a flow rate of 0.5 ml/min. A JASCO
chromatography system equipped with a variable wavelength ultraviolet monitor (JASCO, UV2075 plus, intelligent UV/Vis detector) was set up in tandem with a Canberra flow through NaI
radioactivity detector (TI). Ultraviolet absorption and radiochromatogram was monitored at 254
nm. Chromatography was acquired and analyzed using BORWIN software.
Electrophoresis measurements were carried out in 0.1 M sodium borate buffer (pH 8) using
Whatman No.1 chromatography paper. The paper was presoaked in the same buffer for 5 minutes
before spotting the radiolabeled sample at the middle of the paper. After a potential of 160 V wasapplied for 120 min, the chromatography paper was dried, and the distribution of radioactivity wasmeasured in a γ-well counter. The radiochemical purity of the prepared complex was determined byspotting on ITLC-SG strips.
The biodistribution experiments for the 99mTc complex were performed in normal female mice
to ascertain. the in vivo distribution profile of the radiotracers according to literature [16]. The
animal biodistribution experiments were performed in accordance with institutional, national andinternational regulations governing the safe and humane use of laboratory animals in research.
Mice (BALB/C, 25–30 g) were injected via the tail vein with 0.1 ml of the radiotracer formulated
in saline. Each dose contained 20-30 μCi of radioactivity. Animals were sacrificed at 5, 30 and 60
min post injection and the organs of interest and blood were collected, weighed, and theradioactivity was measured with an automatic gamma counter (Cobra II). The percentage of theinjected dose per gram was then calculated for all tissues using a stored sample of the injection
solution to estimate the total dose injected per mouse.
3.2 Synthesis of [ReO(mer)(amino)OH (H2O)2].
NaReO4 (1mmol, 0.273 g) was added to a solution of SnCl2 (1mmol, 0.256 g) in citric acid (0.5M,
5ml). Amino (1mmol, 0.1004 g) and (mer) (2 mmol, 0.334 g) in ethanol were added dropwise to the
mixture. The reaction mixture was stirred at room temperature for 3hr. The pH was adjusted to 9
with NaOH (0.5M), and the precipitate was recrystallized in hot Methanol and acetone according toliterature [17]. Attempts to make a single crystal were unsuccessful and the complex was
precipitated in micro crystalline form with 98 % yield of the compound: Anal. Calc.(found) for
C10H12N3O4S3Re: C, 23.12(23.46); H, 2.30 (2.05); N, 8.10(8.64); Re,35.8 (36.01)%. IR (KBr, υ/cm1): 908 (Re=O), 606(Re-N), 430(Re-O), 561(Re-S). 1H NMR (d6-DMSO, ppm): 3.4 (s,NH),
7.6(t,Ha), 7.2-7.4(m, Hb, Hc), 7.9(s, Hd) , 7(d, CH=C-N), 6.68(d, CH=C-S). 13C NMR (d6-DMSO,
ppm): 122,124,129 (Ph-ring C=C), 107(C-S), 113(mer C=C-C-S), 141(C=C-C-N), 138(CH-C-N),
169(C=N), 190(C=S). UV-Vis (H2O; λmax[nm](ε; dm3mol-1cm-1): 204 nm( 1899), 321 nm(2459),
332 nm(1899). MS (m/z): 520.2[M]+.
3.3 Synthesis of [99mTcO(mer)(amino)OH (H2O)2]

Direct method: .A
The preparation of the 99mTc-complex was achieved by addition of sodium borohydride (0.29mmol , 11.1 mg) in freshly prepared saline to a mixture containing 99mTcO4- (0.7 ml, 27 mCi) andligands (mer: 9.0 mg, 0.1 mmol ; Amino: 9.9 mg, 0.10 mmol ) with stirring. The mixture wasallowed to stand for 45 min for complete reaction and then extracted with dichloromethane (3x1.5
ml). The combined organic extracts were dried over MgSO4, which was filtered off. The
radioactivity content of both the aqueous and organic phase is measured separately. The organic
solvent was expelled under a mild stream of nitrogen, and ethanol was added. 30% ethanol final
solution was obtained for complex according to literature [16]. The radiolabeling yield was 88 ± 3%with ˃96% radiochemical purity.
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ligand exchange method: .B
Preparation of the
Tc complex was accomplished using
Tc-gluconate as the precursor[16]. A vial containing a lyophilized mixture of 200 mg sodium gluconate and 0.2 mg of
SnCl2.2H2O was reconstituted with 5 ml of water. A volume of 0.5 ml of this solution was mixed
with [99mTc] NaTcO4 1mmol {(0.5–1 ml with an activity of 5–50 mCi (185–1850 MBq)}. The
precursor 99mTc-gluconate, (radiochemical purity > 95%) was added to a centrifuge tube containing
the mixed ligands. The mixture was stirred in a vortex mixer and left to react at room temperaturefor 10 min. The complex was extracted with dichloromethane (3x1.5 ml) and the organic layer wasdried with MgSO4, filtered and analyzed by ITLC and HPLC.
99m

99m

Results and Discussion
The reaction between oxorhenium citrate and the mixed ligands system mercaptobenzothiazole/
Aminothiazole lead to the formation of a [ReO(mer)(Amino) OH(H2O)2] complex according to
Scheme 1.
99m

ReO4-

TcO4-

pH=9
NaBH4
r.t
45min
99m

Na-gluconate

Citric acid

SnCl2. 2H2O

SnCl2. 2H2O

TcO(gluc)2-

ReO(Citrate)2-

S SH
N

N

+

S

NH2

H2O O OH2
S
S

N

M

NH

OH N S

were M=Re,99mTc

Scheme 1.

We found that the labeling yield of the final 99mTc complex was higher when the direct reduction
method was used compared with the ligand exchange method.
Table 2 presents the atomic charges from the Natural Population Analysis (NPA) for[ReO(mer)(Amino)OH (H2O)2]. The calculated charge on the rhenium atom is considerably lower
than the formal charge of +5. This difference is a result of significant charge donation from theOxo, OH and N-ligand donors. The charge on the Oxo ligand is significantly smaller than (-2) andless negative than the charge on the OH ligand, indicating that there is higher electron density
delocalization from the Oxo core to the rhenium [20].
4.1 Geometry optimization, charge distribution, electronic structure and NBO analysis:
The geometry of the [ReO(mer)(Amino)OH (H2O)2]complex was optimized in a single state by
the DFT method with the B3LYP function as shown in Fig1. The calculated bond lengths andangles for Re=O, Re-N and Re-O are in quite good agreement with the values reported for other
oxorhenium complexes of related structure as listed in Table 1 [18, 19].

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Table 1. Some geometrically optimized bond length(A0)and angles(0) for [ReO(mer)(Amino)OH (H2O)2].

Bond length (A0)Re(1)-O(28)1.7196(1.7071)
Re(1)-O(28)1.9253(1.8662)
Re(1)-N(2)2.0531(1.9322)
Re(1)-S(10)2.355(2.233)Re(1)-O(11)1.9253 (1.862)
Re(1)-O(29)2.1676(1.9322)
N(2)-C(4)1.3998(1.398)
N(10)-C(4)1.4066(1.398)

Bond angle (o)O(28)-Re(1)-O(11)B3LYP/LANL2DZ [19 ]170.9908 (170.7782)

S(27)-Re(1)-N(2)172.2611 (171.792)

N(2)-Re(1)-O(28)109.4543 (109.260)

N(2)-Re(1)-O(31)93.4614 (120.723)

N(2)-Re(1)-O(11) 102.2092(102.792)
N(2)-Re(1)-O(29)90.0916 (102.792)

O(28)-Re(1)-O(11) 99.2639(100.07)
Re(1)-O(31)-H(32) 117.5155 (116.99)

Fig.1. The Optimized structure of [ReO(mer)(Amino)OH (H2O)2].
Table 2. Atomic charges from the natural population anaylsis (NPA) for [ReO(mer)(Amino)OH(H2O)2].

Atom
Re(1)
N(2)
S(27)
O(11)
O(28)

Atomic charge
1.437-0.475-0.562-0.413-0.742

Table 3 presents the occupancy and hybridization of the calculated Re-O bond orbitals (NBOs)
for the [ReO(mer)(Amino)OH (H2O)2] complex. Three natural bond orbitals were detected for thecore Re-O bond, and one bond orbital was observed for the Re-O bond of the OH ligand. The Re-O
bond orbital of σ-character is polarized toward the O atoms, and the s and d-orbitals of the Re
participate in the bonding. The Re-O bond orbitals of π character are significantly polarized towards
the metal atom and only the d-orbitals of Re are included into the bonding. The complex adopts a
distorted octahedral structure in which two water molecule is weakly coordinated to the Re atom, as
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seen from the unusual bond length of 2.1676 pm. It is worth mentioning that these calculations are
performed in the gas phase. Dissolution of the investigated complex in aqueous medium could
result in another H2O molecule being coordinated to the rhenium to form a distorted octahedral
structure. These results were further confirmed by measuring UV-Vis spectra of the complex indifferent solvents; shifts in λmax were recorded by changing the solvent, which indicatescoordination of an additional solvent molecule with the Re atom to complete the octahedral
geometry typically found for Re=O complexes [20].
Table 3. The occupancies and hybridization of the calculated Re-O natural bond orbitals (NBOs) for[ReO(mer)(Amino) OH(H2O)2].

BD
Re(1)≡O(28)Re(1)-O(11)Re(1)-N(2)Occupancy
1.95735(0.2786)
1.78553(0.2268)
1.78648(0.1699)
1.89301(0.1667)
1.88269(0.1662)
1.89452( 0.200)

Hybridization of NBO
0.5196(sd)Re+ 0.8544(sp)O0.3809(d)Re + 0.9246(p)O0.4145(d) Re + 0.9101(p)O0.3359(sd) Re + 0.9419(p)O0.2906(d) Re + 0.9569(p)O0.4653(d) Re + 0.8852(p)N

Table 4 compares the calculated and observed vibrational modes of [ReO(mer)(Amino)
OH(H2O)2]. Although one must normally scale the theoretical data by optimal scaling factors,
which vary by basis set, the theoretical values are usually higher than the experimental data. Figs 2,
3 show experimentally and theoretically calculated IR spectra of complex. In our case study,
however, there was good agreement between the theoretical and experimental data.

Fig.2 The IR of [ReO(mer)(Amino)OH (H2O)2] complex.

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Fig.3 The Theortical IR of [ReO(mer)(Amino)OH (H2O)2].

In the IR, (Fig 2) the strong ν(Re=O) bond of the [ReO(mer)(Amino)OH (H2O)2 ] complex was
found in the narrow range around 908 cm-1. This value is in the lower end of the range observed
for a [ReO]3+ core, and suggests that the Re-hydroxy bond competes effectively. In many
investigated studies concerning the M=Ooxo distances in complexes containing the Ooxo=M-Otransfragment, they found demonstrated that when the trans ligand is an alcoholate RO- anion, which is avery strong Lewis base, the M=Ooxo distance is long, and the M-Otrans distance is very short. The
short bond distance is reflected in a high value of the ν(M=Ooxo) stretching mode,
where M=Re, Tc [18, 20].
Table 4. Comparision of the calculated and observed vibrational modes of [ReO(mer)(Amino) OH(H2O)2].

Experimental
524
568
908
524
1356
3440
3114

B3LYP/LAN2DZ
694
730
988
370
1460
3494
3162

Assignment
ν Re-Nν Re-Sν Re=Oν Re-Oν OHbendν OHstr
ν NH

In Electronic spectra (Fig. 4 ) the experimental and calculated electronic spectra for[ReO(mer)(Amino)OH (H2O)2] complex using time-dependent density functional theory TD-DFTof the complex are presented in Table 5. The experimental absorption band at 204 is attributed
mainly to intraligand transitions. The band recorded at 321 nm and 323 nm could be attributed to
LMCT ligand metal charge transition from π-oxgyen-bonding orbital to the d orbital of the
Rhenium [18, 21].

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011A bs

U n ti t le d

2 00 .0

3 00 .0
W av el en g t h ( n m )2 .00 0

1 .00 0

4 00 .0

Fig 4. The UV-vis spectra of [ReO(mer)(Amino)OH(H2O)2].
Table 5. The expermentail elctronic data.

Character
π→π*
LMCT
LMCT

Experimental data in different
solvent λmax nm., (ε; dm3mol1cm-1)
191(2583), 204(2459)
321(2459)
332(1899)

ε- molar absorption coefficient.

Fig.5. The 1H NMR of [ReO(mer)(Amino)OH (H2O)2] complex.

The 1H NMR spectra of a mercapto-ligand show signals assigned to the Ha,b,c,d (the protons of
the benzene ring) in different chemical shifts caused by the anisotropic effect, which laminated theprotons oriented toward the oxygen that appear deshielded relative to the other protons oriented
away from the oxygen ( toward or away from the oxo-metal core) [18]. As we see the Ha,d near the
Re=O core was assigned to the downfield region of the spectrum at~7.7-7.6 ppm. The NH2 proton
signals for the amino ligand were absent in the spectrum of the complex and only a signal due to an
NH group was recorded at 3.4. The 13C NMR spectra of the complex exhibit two new characteristic
peaks for C=S and C-N at lower fields of 189 and 141 ppm compared with the spectra of free ligand
mer, indicating that coordination via the charged thiolic sulfur and nitrogen atoms occurred. In
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Fig.6, the signals at 139 and 107 ppm attributed to the (CH=C-N) bond and (C-S) bond,respectively. In addition, the spectrum showed signals assignable to the (C=N) bond at 169 ppm ofAmino ligand.

Fig 6. The 13C NMR of [ReO(mer)(Amino)OH(H2O)2].

4.2 Quality Control of the 99mTc complex.
The [99mTcO(mer)(Amino)OH(H2O)2] complex can be prepared in two-steps. Quality control ofthe [99mTcO(mer) (Amino)OH (H2O)2] complex was performed by thin-layer chromatography(TLC) and high-performance liquid chromatography (HPLC). The final 99mTc-oxo hetero complex[99mTcO(mer)(Amino) OH(H2O)2] was obtained in high yield (>97%). TLC and HPLC analyses
were used to evaluate the radiochemical purity (RCP) and the stability of the complex. ITLC was
performed on instant thin layer chromatography with Whatman No.1 chromatography paper andusing acetone and saline as the mobile phase according to literature [16]. The Rf values for[99mTcO(mer)(Amino)OH (H2O)2] were around 0.78 in acetone; the other values are reported inTable 6.
Table 6. The Rf values of compounds in acetone.

CompoundRf[99mTcO4]0.9[99mTcO(gluco)2]intermediate
0.8-1[99mTcO-Complex]
0.78

The HPLC chromatograms of the [99mTcO (gluconate)2]- intermediate and[ TcO(mer)(Amino)OH (H2O)2] are shown in (Fig 7). The retention time of the final 99mTc-oxo
complex [99mTcO(mer)(Amino)OH (H2O)2] was found to be about 9.6 min, and that of [99mTcO(gluconate)2]- intermediate was 15.6 min. Their characterization was made using HPLC comparing
their retention time (γ detection) with the retention time of the well-defined analogous rhenium
complex (UV detection at 254 nm). The paper electrophoresis pattern of showed that the[99mTcO(mer)(Amino)OH (H2O)2] complex, the larger fraction of radioactivity reside at the neutral
point with negligible wings toward either sides. (Fig 8 ).
Corroboration of structure of the 99mTc-complex was achieved by comparing its HPLC profiles
with the corresponding to the Re-complex. Radioactivity and U.V detectors showed identicalchromatographic profiles, suggesting that the same chemical structure was formed under bothsynthesis conditions.
99m

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Fig.7. Chromatography ITLC TLC chromatographyof mixture(a) reaction in acetone, (b) organic layearin saline, (c) organic layer in acetone .

Fig.8. HPLC radio chromatogram for the[99mTc(mer)(Amino) OH(H2O)2]and[ReO(mer)(Amino)OH(H2O)2].

In vitro stability of the complex was evaluated by measuring the RCP in ITLC at different time
points. The RCP was still over 97% after 5 h, which suggested that the complex[99mTcO(mer)(Amino) OH(H2O)2] possessed great stability in vitro. Stability studies of the 99mTc
complex as summarized in Table 7, found that the complex is stable in saline and plasma for at least
5 hours, which is an important parameter to pursue with biological studies. The lipophilicity of thecompound was evaluated by determination of the partition coefficient (P) in physiologicalconditions (n-octanol/ saline). The results obtained, were expressed as log PO/W and the data wererepresented as the mean ± 0.07 the standard deviation is - 0.153. As expected, the compound has
low lipophilicity [22]. As expected, there is increase of the lipophilicity of complexes 99mTcO [SN]when the benzene ring attached to the mercapto ring the logP above 1.5. The 99mTcO [SN] complex[23], is low lipophilicity it's more hydroliphilic than mercapto-ring complexes. It seems that theamino attachment increase the hydrophilic properties to the complex.
Complex 3
90
80
70
60
Relative 50
Activity 40
30
20
10
0
1

2

3

(+)

0

(-)

Fig. 9. Electrophoresis histograms of [99mTc(mer)(Amino) OH(H2O)2]; (+)Anode; (-) Cathode; (0) neutral.
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Table 7. The Stability of compound in Saline/Plasma.

Compound

Log PO/W
Saline stability (%)- 0.153 ± 0.07

10 min 30 min
77

99

Plasma stability (%)

1h

3h

10 min

79

70

07

30
min
46

1h

3h

55

54

Complex 3
salineplasma120

Complex 3

100
80
60
40
20
0
0

10

30

60

120

180

Tim e (m in)

Fig .10. Stability of complex of [ 99mTc(mer)(Amino) OH(H2O)2] in plasma and in saline.

The animal biodistribution experiments using [99mTcO(mer)(Amino)OH (H2O)2] were performedin accordance with institutional, national and international regulations governing the safe andhumane use of laboratory animals in research. In Table 8, the complex is seen to have a significant
low brain uptake. The blood uptake was low and its clearance was fast so that the brain/blood ratio
was stable, 0.055, 0.062, and 0.057 at 5, 30 and 60 min post-injection, respectively. The complex
has exhibited high initial lung and spleen uptake. The liver uptake was significant and remained
high at 60 min post-injection, suggesting the hepatobiliary system is the major route of excretion of
the administered radioactivity. Hepatobiliary clearance of the complex is inferable from thegradually increasing activity in the intestinal tissue 30 min p.i. It was pertinent to compare thebiodistribution parameters with that of [99mTcN(NOEt)2] [24]. The results indicate that a structuralmodification is required in the design of the ligand. Increasing the polar nature of the final
compound could be envisaged as a possibility to reduce the lipophilicity of the complex [25]. Thiscan be achieved by incorporating polar substituents consisting of O, N, CO donor atoms on theligand backbone, which in turn, will increases the clearance of the complex from the blood [5].
Additionally, it has been documented that suitable modifications such as increase in the number
aliphatic substituent in the molecule enhances its clearance from liver, lungs, etc. [23] due to fast
metabolism [24]. A large fraction of the activity (35%) can be seen in the kidneys, which could
possibly be due to the small size of the complex [15]. The activity appears to be retained for a longtime in the kidney, diminishing a certain extent at 60 min, perhaps owing to the metabolism of thecomplex within the kidney. One reason could be that the pendent free primary amino group of 99mTc
complex can be regarded as mimicking the-amino group of lysine [25]. Since the pK-value of thisamino group is approximately 10.5, a similar value is assumed for the free amino group of complex[24]. At physiological conditions this amino group is protonated and thus positively charged. Reabsorption by the negatively charged membrane of the proximal tubule cells enhance renal
accumulation by the attractive effect exhibited by the two opposing charges [25].

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Table.8. The distibution data for Complex as %ID/gm in mice at different time intervals.

Organ
Brain
Blood
Liver
Lung
KidneyIntestineHeart
MuscleSpleen5 min
0.58±0.12
10.58±5.92
18.73±10.31
19.2±7.99
14.60±27.25
11.78±0.57
3.21±1.12
0.89±0.16
19.5±10.77

30 min0.45±0.09
7.30±2.35
12.23±9.18
16.96±9.77
12.95±7.40
10.78±16.79
3.40±2.08
0.75±0.39
14.55±9.75

60 min0.23±0.03
4.07±0.72
12.92±2.63
14.32±7.228.55±1.30
10.56±17.36
2.46±0.49
0.47±0.09
10.33±7.71

Conclusion:
The oxorhenium complex was synthesized based on the [S/N] [N], mixed ligand system and fully
characterized at the macroscopic level. In this complex, a novel complex [99mTcO(mer)(Amino)OH(H2O)2] was formed using (mer) mercaptobenzothiole ligand and (Amino) Aminothazole ligand
and the [ReO]+3 core. The chemistry was successfully transferred at the tracer level, and thecorresponding oxotechnetium-99m complex was prepared using 99mTc-gluconate and by direct
reduction of pertechnetate in the presence of N/S mixed ligand. Its structure was established bycomparative HPLC analysis using the oxorhenium complex as a reference. Tissue distribution
studies in normal mice demonstrated.
The Acknowledgment:
The Author extends the appreciation to the Deanship of Scientific Research at King Saud
University for funding the work through the research group project NO. ( RGP-VPP-041)
References:
1.

2.
3.

4.

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Jurisson. S. S., Lever. S. Z., Lydon J. D. and Cutler C. S. (2004) New York. Radioactive
Metal in Imaging and Therapy Comprehensive Coordination Chemistry II, Chapter 9, Pages
883-911.
Schwochau, K. (2000) Techenetuim Chemistry and Radiopharmaceutical Applications.
Wiley-VCH.
Papagiannopoulou. D., Pirmettis .I. C., Pelecanou. M., Tsoukalas. Ch,. Raptopoulou. C.P.,
Terzis. A., Chiotellis. E and Papadopoulos. M. (2001) Synthesis and structuralcharacterization of a novel Re[P][NN][S][SO] mixed ligand rhenium (III) complex.
Inorg.Chim.Acta, 320, 174-177.
Zhang.H., Dai. M., Qi.C., Li. B., Guo. X (2004) Synthesis, biodistribution and quantitative
structure-activity relationship studies of new 99mTc labeled pseudo-peptide complexes. Appl.
Radiat. Isot, 60, 643–651.
Dhara. B., Chattopadhyay.P. (2005) New oxorhenium(V) complexes with 2N2S donor sets
and radiochemical behavior of their technetium analogs. Appl.Radiat.Isot, 62,729-735.
Shan.S., Ellern. A., Espenson. J.H. (2002) Methyloxorhenium(V) complexes with twobidentate ligands. Inorg. Chem, 41, 7136–7142.
Gancheff. J., Kremer.C. Kremer. E and Ventura .O (2002) Density functional study oftechnetium and rhenium compounds. Theochem, 580,107-116.
Machura. B., Penczek. R., Kruszynski. R. (2007) Synthesis, crystal, molecular, andelectronic structure of [ReOCl3(bpzm)] complex. Polyhedron, 26,(12, 23), 2581-2588.
Gaussian 98 program ,Gaussian , Inc. pittsburgh. PPA 15106 USA.
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10.
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Becke A. D, Pérez-Jordá.J. (1995) A density-functional study of van der Waals forces: raregas diatomics. Chem. Phys. Lett., 233(1-2) 134-137.
Parr, R. G., Liu .S. (2000) Homogeneities in density of various LDA energy functional.
J.Mol. Struct: THEOCHEM, 501-502, 29-34.
Hay. P.J., Chen. S.P., Voter. A.F,. Albers. R.C., Boring. A.M. (1989) Theoretical studies ofgrain boundaries in Ni3Al with boron or sulfur. Scripta Metall, 23(2) 217-222.
Casida. M.E..,in: J.M.Seminario (Ed); Recent Development and Applications in Modern
Density Functional Theory, Theoretical and computational Chemistry, Vol.4, Elsevier
Amsterdam, (1996).
Glendening. E.D, Reed, A.E,Carpenter .J.E and Weinhold. F, NBO (version 3.1).
Pelecanou. M., Pirmettis. I. C., Nock. B. A., Papadopoulos. M., Chiotellis. E.,
Stassinopoulou C. I. (1998) Interaction of [ReO(SNS) (S)] and [99mTcO(SNS) (S)] mixed
ligand complexes with glutathione: isolation and characterization of the product.
Inorg.Chim. Acta 281, (2),148-152.
Rey. A,, Papadopoulos. M., Leon. E., Mallo. L., Pirmettis. Y., Manta. E., Raptopoulou.C.,
Chiotellis. E., Leon. A. (2001) Synthesis, characterization and biological evaluation of anovel “3 + 1” mixed ligand 99mTc complex having an aliphatic thiol as coligand. Appl.
Radiat. Isot., 54( 3),429-434.
Bouziotis . P., Pirmettis .I., Pelecanou .M., Raptopoulou,. C. P., Terzis. A.,
Papadopoulos.M., and Chiotellis.E,.(2001).Novel Oxorhenium and Oxotechnetium
Complexes from an Aminothiol [NS]/Thiol[S] Mixed-Ligand System. Chem. Eur. J., 7(17).
Gardner. J. K., Durig. J. R., Little. T. S., Gounev. T. K., Sullivan. F. (1996) Infrared andRaman spectra, conformational stability, vibrational assignment, and ab initio calculationsof chloromethyl isocyanate. J.Mol. Struct. 375(22), 83-94
Maresca .K., Femia .F. J., Bonavia .G.H., Babich .J.W. and Zubieta J.(2000) Cationiccomplexes of the ‘3+1’ oxorhenium–thiolate family Inorg. Chim. Acta, 297, 89-105.
Machura, B, Kruszynski, R and Kusz, J (2008). Novel oxorhenium complexes with 2-(20hydroxyphenyl)-2-benzothiazolinato ligand: X-ray studies, spectroscopic characterization
and DFT calculations, Polyhedron. 27, 1679–1689.
Machura, B., Kruszynski, R., Jaworska. M and Lodowski,P. (2005) Reactivity of[ReOX3(PPh3)2] complexes towards 1,4-diaminobenzene: X-ray structure and DFT
calculations. Polyhydedron, 24, 1454-1460.
Giglio. J, Rey. A., Cerecetto. H., Pirmettis. I., Papadopoulos. M., León. E., Monge. A,
López de Ceráin. A, Azqueta. A , González. M., Fernández. M., Paolino. A. and León. A(2006) Design and evaluation of “3 + 1” mixed ligand oxorhenium and oxotechnetium
complexes bearing a nitroaromatic group with potential application in nuclear medicine
oncology. Eur. J. Med .Chem 41 (10), 1144-1152.
Braband. H., Miroslavov. A.E., Lumpov. A.A., Sidorenko. G.V,, Levitskaya. E.M,.
Gorshkov. N.I, Suglobov. D.N., Alberto. R,. Gurzhiy. V.V., Krivovichev. S.V and
Tananaev I.G. (2008) Complexes of technetium (I) (99Tc, 99mTc) pentacarbonyl core with πacceptor ligands (tert-butyl isocyanide and triphenylphosphine). J.Organometal Chem, 693,
4-10.
Tsoukalas. Ch., Pirmettis. I., Patsis.G., Papadopoulos. A., Raptopoulou. C. P, Terzis A.,
Papadopoulos. M., Chiotellis. E. (2001) Ester-modified 99mTcO[SN(R)S/S] mixed ligand
complexes: synthesis and preliminary evaluation. Nucl. Med. Biol, 28, (8), 975-982.
Chattopadhyay, P., Chiu, Y.H., Lo, J.M.,Chung, C.S., Lu, T.H. (2000). Synthesis andstructural characterization of a Re (V) complex with 2N1S donor and radiochemical
behavior of its Tcanalog. Appl. Radiat. Isot. 52, 217–223.

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4.P11.
PREPARATION AND BIOLOGICAL STUDY OF «NANOTECH, 99mTc»
N.A. Taratonenkova, A.O. Malysheva, G.E. Kodina, O.E. Klementyeva.
Burnasyan Federal Medical Biophysical Center FMBA Russia (Zhivopisnaya st. 46, Moscow, Russian Federation)

Keywords: technetium-99m, rhenium sulfide colloid, nanocolloid, sentinel lymph node,
lymphoscintigraphy
Abstract:

An early radiopharmaceutical used to image the lymphatic system was 198Au-colloid, having auniform particle size of 3–5 µm in diameter. However, this agent is not readily available today
because of clinical limitations from its isotope being a ß-emitter and emitting an unfavorable -rayfor scintillation camera imaging and because of the difficulties its manufacture. Other widely usedtechnetium-bound radiopharmaceuticals are 99mTc-rhenium sulfide colloid and 99mTc-nanocolloid.
99m
Tc-nanocolloid is used extensively in Europe, and similar preparations are available(NANOCOLL and ALBU-Res; Nycomed-Amersham Sorin, Milan, Italy). These products result ingood lymph uptake and images of flow, but poor retention limits their use in delayed images. The
domestic radiopharmaceuticals (RPh) used for this purpose are absent nowadays and the foreign
kits does not purchase since 2006. During the investigation we developed a simple technology of kit
production and preparation of radiopharmaceutical on its base. All preclinical trials were carriedout with this RPh.
Introduction

The concept of sentinel lymph node imaging is one of the most interesting recent developments on
clinical oncology that holds the promise of a major breakthrough in the detection and treatment ofearly lymphatic metastasis from solid tumors, mainly melanoma and breast cancer. The sentinelnode is the first lymph node to receive lymphatic drainage from a tumor site and therefore, it is themost suitable tissue for histological examination. In lymphoscintigraphy, a radiopharmaceuticalshould move at a rate similar to that of the physiologic flow of lymph and should be sufficiently
retained by intervening nodes. Colloids are highly desirable for such studies because their
particulate nature allows them to be retained by the lymph nodes by a phagocytic mechanism, yet
the rate of colloid transport through the lymphatic channels is directly related to their particle size.
Particles smaller than 4–5 nm have been reported to penetrate capillary membranes and therefore
may be unavailable to migrate through the lymphatic channel. In contrast, larger particles ( 500 nm)
clear very slowly from the interstitial space and accumulate poorly in the lymph nodes or aretrapped in the first node of a lymphatic chain so that the extent of nodal drainage in contiguous areas
cannot always be discerned. After injection, the radiocolloid travels to the sentinel node throughafferent subcapsular lymphatics, where they are retained by the sinusoids and phagocytosed by thereticuloendothelial macrophages of the node. Particles smaller than 100 nm show the most rapid
disappearance from the interstitial space into the lymphatic channels with good retention in thelymph node. Most larger particles do not move easily beyond the first node site encountered. The
permeability of colloids in lymph is maximal for particles smaller than 50 nm. The new procedureof intra-operative lymphatic mapping demands corresponding radiopharmaceuticals with particle
size 50 – 100 nm, which now are absent in Russia. The aim of this work was the development of thesimple method of sol Re2S7 preparation and radiopharmaceutical (“Nanotech, 99mTc”) on its base,investigation of biodistribution in experimental animals. In this work we compared two methods ofsol preparation, using so called “dry” and “wet” technology.
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Experimental
Synthesis of sol (rhenium sulfide) was carried out according to two technologies. We called them “wet”(used solutions of chemicals) or “dry” (dry chemicals dissolved in the gelatin solution) technology.
Scheme of this synthesis is presented on Fig. 1.
“Wet” technology“Dry” technology

Fig. 1. Sheme of sol synthesis

Preparation of radiopharmaceutical “Nanotech, 99mTc:
The kit of reagents consists of two vials: vial 1 with 1 ml of rhenium sulfide sol and vial 2 withlyophilized mixture of tin dichloride, sodium pyrophosphate and ascorbic acid. 2,0 ml of water for
injection was introduced in the vial 2. The vial was shaken to dissolve the lyophilized reagent. Then
0,5 ml from the vial 2 and 2,0 ml of eluate from 99Mo/99mTc generator were added to the vial 1 withsol Re2S7. The vial 1 was placed in the boiling water-bath for 30 min. Then the vial was cooled in
the ice-water-bath to the room temperature for about 5 min.
Determination of radiochemical purity (RCP):
RCP was determined using paper chromatography on Whatman 1 in methyl-ethyl-keton using“MiniScan” (USA). In this system pertechnetate-ions (impurity) migrate with solvent front (Rf =1),
colloid remains on start of the strip (Rf =0).
Determination of particle size:
The dymanic diameter of particles was determined using a light-scattering photon correlation
spectroscopy on NICOMPTM 380ZLS (USA).
Results and Discussion.
Colloidal form of hentasulfide rhenium can be obtained via the following reactions:
2NaReO4+7Na2S2O3+2HCl Re2S7(col.)+ 7Na2SO3 + 2NaCl +H2O
2NaReO4 + 7Na2S + 16HCl Re2S7(col.) + 16NaCl + 8H2O
Simultaniously the side reactions take place, so the losses of rhenium during sol preparation are
inevitable.
Na2S2O3 + 2HCl  2NaCl + SO2 + S(col.) + H2O
NaReO4 + Na2S2O3 + HCl  reduced chemical forms of Re + S(col.)NaReO4 + Na2S + HCl  reduced chemical forms of Re + S(col.)
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All mentioned above reactions proceed with noticeable rate only during heating.
During sol preparation the influence of the following main reaction conditions were studied:molar ratio Na2S2O3 / NaReO4 was changed from 1,75 to 3,5; time of reaction was changed from 5
to 10 minutes. It was found for all molar ratios if time of the reaction less than 6 min – the obtained
product is light coloured, if the time of the reaction more than 6 min the precipitate is obtained. The
results of sol preparation is shown in Table 1.
Table 1. The results of sol preparation.
Na2S2O3 / NaReO4

Time, minResults

1,75

5–6
10
5–6
10
5–6
10
5–6
10

sol
precipitatesol
precipitatesol
precipitatesol (hardly filtered)precipitate

2,2
2,7
3,5

The yield of sol was determined by TLC (acetone – silica gel) using

188

Re as label during thesynthesis. As shown in Table 2, sol yield was about 30 % and did not depend on technology of it
synthesis.
Table 2. Yield of sol Re2S7
Colloid(Rf =0)

ReO4(Rf =1)“Wet” technology

24,0 %

69,2 %“Dry” technology

27,1 %

70,0 %

Methods ofsynthesis

Colloidal particle size is an important characteristic to consider when choosing aradiopharmaceutical for mapping sentinel nodes in lymphoscintigraphy. The dymanic diameter ofparticles was determined using a light-scattering photon correlation spectroscopy on NICOMPTM
380ZLS. Dynamic diameter of sol particles is shown in Table 3. Dynamic diameter of particles in
the ready-to-use radiopharmaceutical was in the range 15 – 50 nm.
Table 3. Dynamic diameter of sol particles

Method of synthesis

D, nm
D, nm
(before sol filtration)(after sol filtration)“Wet” technology
from 25 to 90
from 25 to 80“Dry” technology
from 20 to 190
from 20 to 70
In Table 4 the results of determination of radiodhemical purity in “Nanotech, 99mTc” and pH of RPhare shown. From presented results we can conclude that radiopharmeceuticals with RCP more than
90 % were obtained at molar ratio Na2S2O3 / NaReO4 2,2 - 2,7.
Table 4. Determination of radiochemical purity (RCP) of RPh

Na2S2O3 /NaReO4
1,75
2,2
2,7
3,5

Time ofsynthesis. min
66
6
6

TcO4-, %RCP, %

рН

7,4
4,5
4,3
12,4

84,4
91,3
91,9
72,6

5,5
5,8
5,6
5,5
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The preliminary biological results were shown on Fig.2 and 3. 0,1 ml of RPh «Nanotech, 99mTc»
was injected into the plantar of the right limb of rats. Dymanic investigations were carried out
during 15 min post injection, investigation in static - after 1 and 2 h post injection.

Fig. 2. Accumulation in the inguinal lymph
node during 15 min (Y – arbitrary units –ratio of accumulation to the injected dose)

Fig. 3. Accumulation in the inguinal lymph node
after 2 h post injection.

Conclusions.
Two methods of sol Re2S7 synthesis were compared (“dry” and “wet” technology). It was
found: optimal molar ratio Na2S2O3 /NaReO4 – 2,2, time of synthesis – 6 min. During the
production in commercial scale “Dry” technology allows more easer to increase the volume of sol
batch. The yield of sol (using 188Re as label during synthesis) via “dry” or “wet” technology does
not differ and is about 30 %. The mean diameter of sol particles (Re2S7 ) - 20 - 80 nm. RCP ofradiopharmaceutical is more than 90,0 %. According to the results of the biological investigations
the maximum uptake in the inguinal lymph node was obtained at molar ratio of Na2S2O3 / NaReO4= 2,2. Nowadays the preclinical trials with “Nanotech, 99mTc” were carried out.

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4.P12.
SORPTION REMOVAL OF Na99mTcО4 FROM EXTRACTS OF
EXTRACTION GENERATOR 99Mo/99mTc
Reshetnik Y.N., Bykov A.N., Kodina G.Е., Malysheva A.O.
Burnazyan Federal Medical Biophysical Center, Moscow, UNReshetnik@runtech.ru

Extraction technology of 99mTc from irradiated natural Mo or enriched with 98Mo is wellknown during more than 30 years [1]. Nevertheless, in the conditions of the ongoing "99Mo -crisis",as well as environmental reasons, an alternative in relation to fission 99Mo and 99mTc production
methods have received in recent years a new development.
In such method 99mTc is extracted from the alkaline solution of irradiated Mo by methyl
ethyl ketone (MEK) with the subsequent evaporation to dryness and dissolution of the residue in thesaline [2]. This technology more than 20 years is successfully used in Russia as well [3,4].
However, the evaporation of organic solution is the most long-term and insecure operation, in
addition, the full automation of process in such performance is difficult to implement.
In the present work we studied 99mTc sorption behavior when removing it from MEK
without stage of extract evaporation
As a result of experiments it was established that 99mTc can be sorbed on alumina (Merck,
0,06-0.20 mm) in both acidic and alkaline forms from MEK solutions pre-cleared out of cations
abundance on ion exchange resin (Dowex, 50W-X8, 100-200 mesh). After washing of alumina withwater 99mTc in the 99mTcO4- form can easily be desorbed with saline. The table presents the resultsof determining the 99mTc output in sorption stages and process in general.
№

Column 1(Dowex)
Sorbtion,
Eluate,Column 2 (alumina)
Sorbtion, %Washing ,Yield
Eluate,
%

1
2
3
4
5

%
4,3
7,7
6,2
3,2
2,0

%
95,7
92,3
93,8
96,8
98,0

(% from initial)
99,9 (95,6)
95,8 (88,4)
90,0 (84,4)
89,5 (86,6)
91,3 (89,4)% from initial
2,1
0,5
1,5
1,5
2,5

%
93,0
85,3
89,1
79,9
91,7

86,9
75,0
73,8
74,6
79,4

The MEK content in the final solution ˂˂ 0.5 mg/ml (range, regulated domestic and foreign
pharmacopoeias). Radiochemical purity (RCP) ≥ 99%. The pH values are 6.5 - 7.4. Thus, we canconclude that the final solution Na99mTcO4 is suitable for medical use.
Other 99mTc-radiopharmaceuticals, prepared with the use of the final solution Na99mTcO4
and the domestic 99mTc-kits also comply with pharmacopoeia requirements.
1. Boyd R.E. Radiochem. Acta, 1982, 30 N 3, p. 123 - 145.
2. Melichar F., Svoboda K., Prokop J., Budsky F. IAEA-SM-131-50, Vienna, 1986, p.81.
3. Skuridin V., Glukchov G., Chygriaev M. Extraction generator of technetium-99m. USSR
Priority1426019; С01G 57//00, 14.04.86, reg. 22.05.88.
4. Zykov M.P., Romanovsky V.N., Kodina G.E. et al. J. Radioanalyt. Nucl. Chem., 1997, 221 N 1 2, p. 227 – 230.
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Applications of Tc and Re
in technology, including their alloys
in Modern Constructing Materials

Chairman of the 5-th Session Boris D. Bryskin with welcome
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5.1.
THE FABRICATION DEVELOPMENT OF RHENIUM USED IN HIGHTEMPERATURE ROCKETS AND HIGH TEMPERATURE SPACE POWER
REACTOR
Boris D. Bryskin, Edwin D. Sayre
Abstract
The use of tungsten as the thin liner of high temperature rocket nozzles in solid fuel rockets tended
to produce very brittle tungsten carbide with the graphite nozzle structure underneath. It was foundthat rhenium provided a good bond and it did not react with the graphite and provided a good bondof the tungsten during the entire length of the rocket flow. Rhenium has been found to improve thehigh temperature jet engine blade service by alloying slight amounts in nickel and cobalt hightemperature alloys. In the development of the SP100 Nuclear Space Power System it was foundthat uranium nitride was the ideal fuel and Nb1%Zr alloy tubing was the best fuel cladding.
However it was found that the Nb1%Zr alloy tube reacted with the fuel and fission products at suchhigh operating temperature, (10770C). It was found that rhenium tubing on the inside protected it
for the life of the system. No rhenium tubing to meet the requirements had been produced and none
was available on the market that could be used for the SP100 Nuclear Space Power System. We in
the program had to work with the rhenium sources and develop the rhenium strips needed anddevelop the tube production process. Rhenium-Molybdenum alloy large tubing was developed fornuclear reactor control. This paper is devoted mainly to the development of the two processes formaking the very high quality rhenium tubing. One process produces welded and drawn tubing andthe other process produces seamless drawn tubing.
Introduction
Rocket nozzles for less than a minute solid fuel rockets were made with a steel outer container
coated with high temperature insulation that was coated with thin carbon graphite layer that had theform of the nozzle for the gas flow control. Then a tungsten layer was finally deposited to protect
the carbon and control the flow. Because of the very high operating temperature after less than aminute the carbon would react with the tungsten to make tungsten carbide in the major nozzle inner
layers and the brittle layer would crack and flow out with the rocket exhaust and destroy the rocket
exhaust control and loose the thrust and cause change in course. The rocket nozzle producers foundout from the University of Tennessee that rhenium would be a good barrier layer between thetungsten and the graphite to stop the formation of tungsten carbide.
Aircraft jet engine producers found that rhenium alloyed with turbine blade alloys could increase
the operating temperature and the life of the blades1
When General Electric ran the NASA SP100 Nuclear Space Power System Program they
determined that rhenium was the best barrier between the fissioning fuel and the Nb1%Zr fuel tube.
The development of the two processes for making the rhenium tubes is the major part of this paper.
One process is to make thin rhenium strips, form them into tubing, weld them, heat treat them anddraw them to the final dimensions and properties. The other process is to produce a rhenium
powder metallurgy start tube and draw it to the final dimensions and properties.
Rhenium Between Carbon and Tungsten in Large, Long Time Solid Fuel Rocket Nozzles
While developing the long time, large, solid fuel rocket nozzles it was determined that the tungsten
nozzle liner on the graphite nozzle was reacting with the carbon and produced brittle tungsten
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011carbide which continually cracked and ruined the rocket performance after about 30 seconds.
While developing the longer (2 minutes plus} nozzle we found out from the University ofTennessee that rhenium would make a good barrier metal coating between the carbon and thetungsten layers in the center flow walls of the rocket nozzles. We produced the outer walls of thenozzle as usual and had the university coat the carbon layer with electroplated rhenium. The
rhenium was then finally coated with tungsten in controlled atmosphere system as shown in figure
1. The completed nozzle is shown in figure 2. The nozzle was then tested on a lager space solid
fuel rocket for over 2 minutes with a perfect performance.2 This has become a good usage forrhenium and these nozzles have been used many years in military and space applications.

Figure 1. Controlled Atmosphere Plasma Spray Tank

The Fabrication Development for Rhenium Tubes for Nuclear Space Power Systems
To get the high efficiency from the nuclear space power system SP100 the reactor operating
temperature was established at 10770C. Uranium nitride turns out to be the best fuel for the hightemperature operation. The niobium alloy with 1%zirconium and 0,01% carbon was selected forthe fuel cladding tubes. It had good properties for the high temperature reactor, but it was decided
to use the rhenium bonded to the inside of the fuel tube because it was not nearly as reactive withthe fission products and had a much higher strength at 10770C than the niobium alloy. The final
thicknesses were (<0.25 mm) rhenium bonded inside layer and (<0.75 mm) PWC-11 outside layer.
Initial Approaches
Once rhenium was selected for the inner tubes it was determined that no rhenium tubes wereavailable on the market. Three processes were tried to establish the best for the tubing including
sintered tube shell, vapor deposited and thin strip formed, welded, heat treated and drawn. Using
thin strip, forming it and welding the tube followed by heat treating and drawing turned out to be
the fastest developed satisfactory process to get the fuel tube fabrication going. There was very
little rhenium thin sheet material to use to make welded fine grained tubes so we worked hard withtwo producers to get the high quality rhenium strip under production
Producing the Rolled and Welded Thin Walled Rhenium Tubes
The rhenium strip stock was produced at a thickness of 0.203 mm. Strips for forming the rolled
tubes had to be cut very accurately. The strip had to be heat treated to get the minimum hardness
for cutting. Several methods were tried for very accurately cutting the final strips for rolling.
Mechanical cutting would not be accurately enough because of the very high hardening at the
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cutting line. Elctrodischarge machining wound up being the successful cutting process. It required
chemical cleaning after cutting.
Hydraulic forming was used to form the tubes3. The tube forming was very critical because theminimize gap along the weld line is extremely critical. The successful electron beam weld requireda maximum gap of less than 0.051 mm and a mismatch of less than 9,938 mm. The weld grains
were large and sometimes single ones were from edge to edge as shown in figure 3. These throughwall grains tended to rupture during drawing the welded tubes. To solve this problem the welds
were shot peened and heat treated to get the grains reduced in size before the drawing of the tubes.
The tubes were then drawn and heat treated to wind up as thin walled fine grained rhenium tubes
with the same metallurgical characteristics as any drawn tubes. The welded tubes, after the weld isshown on the left in figure 3 and after the first drawing they look like the right side of figure 3. The
tubes are then drawn and heat treated several times until they reach the final size.

Figure 3. Heat Treatment and Cold Working Effect on Welded Rhenium

After the final draw and heat treatment to final size the rhenium tubes are very soft and this is an
important factor in bonding the rhenium tubes inside the niobium alloy tubes4. It makes it possible
for the tubes to tighten without cracking during the HIPing bonding.
Bonding the Rhenium Tubes on the Inside of the Niobium Alloy Fuel Tubes
When we had both rhenium and PWC-11 tubes meeting all the properties we started thedevelopment of the bonding process. Because of the very thin tubes it was decided to use HIPing toprovide the heat and pressure to make the bond. In order to HIP bond the two tubes we needed amethod to metallurgically bond the two ends with a very good vacuum between the tubes. We
found that vanadium was the ideal metal to bond the ends. It has high melting point and bonds wellto both metals. The tubes were machined at the ends to provide a gap for inserting the vanadiumrings3. The tubes were brazed in vacuum with EB welding. The tubes were then HIPed and bonded
very well. The brazed ends were cut off HIPing and left solid niobium alloy tubes with well bonded
rhenium inside. A micro picture of the bonded tube is shown in figure 4. Several completed tubes
are shown in the vacuum heat treatment furnace in figure 5.
Making Seamless Rhenium Tube From Rhenium Powder
The extended development of rhenium seamless tubing by former Sandvik Rhenium Alloys, Inc.
with application of Powder Metallurgy was conducted through the following manufacturing steps:pressing, presintering and sintering of rhenium metal powder reduced from ammonium permeate.
The sintered tube was cold swaged over a mandrel of molybdenum high speed steel to consolidate
structure and decrease diameter and wall thickness. Further deformation by repeating cold drawing
on hardening steel mandrel through carbide dies to approximately 0.010 – 0.007” wall with
reduction 5.8% per pass was applied. Intermediate annealing of tubes at 1500 – 1800C up to 5-19
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min. in hydrogen was introduced. Attempt to deform sintered tube by cold pilfering with reduction
10% was successful and resulted in good surface quality and size precision.

Figure 4. Micro of Rhenium Inner Tube Bonded
to Nb Alloy Outer Tube

Figure 5. Several Finished Bonded Tubes in
The Vacuum Heat Treatment Furnace

References
1. General Electric uses rhenium in the GE 90 jet engine and is recycling the alloy scrap
to optimize the use of new rhenium.
2. Edwin D. Sayre, “Application of Rhenium and Rhenium Containing Alloys”, Evolution of
Refractory/Metals and Alloys”, Edited by N. C. Dalder, Toni Grobstein and Charles S. Olsen, RNS
Annual Meeting, Denver, Colorado, February 21-25, 1993.
3. Edwin D. Sayre, Thomas J. Ruffo, Donald C. Wadekamper, Mike Kangilaski, “Development of
Bonded Rhenium/Niobium-1% Zirconium Tubing For The SP100 Space Reactor”, Rhenium &Rhenium Alloys, Edited by Boris Bryskin, Minerals, Metals & Materials Society International
Symposium held at the 1997 TMS Meeting in Orlando, Florida February 10-13, 1997.
4. Edwin D. Sayre and Thomas Ruffo, “Manufacturing SP100 Rhenium Tubes”, Ninth Symposiumon Space Nuclear Power, Albuquerque, New Mexico, 1992, Proceedings Published by American
Institute of Physics, New York, 1992, 246.

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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 20115.2. MAKING AND SHAPING OF RHENIUM AND RHENIUM
CONTAINING ALLOYS
Todd Leonhardt1 and James Ciulik2

1

Rhenium Alloys, Inc. Elyria, Ohio 44256 USA
The University of Texas at Austin, Department of Mechanical Engineering
Austin, TX 78712-0292 USA

2The focus of this paper is to discuss the advancements in the production ofrhenium and rhenium containing alloys along with science and understanding of the
impact of powder morphology, powder compaction, sintering, and the consolidation
methods of hot isostatic pressing and extrusion.
Rhenium is extremely sensitive to processing conditions because of its highwork-hardening coefficient. This intrinsic property dominates the processing options
available for production. A comparison will be made of the different
densification/compaction processes on the microstructures and mechanical propertiesof powder metallurgy rhenium and rhenium containing alloys of molybdenum andtungsten.
The addition of rhenium in the concentration of 47.5 weight percent rhenium inmolybdenum and 25 weight percent rhenium in tungsten has a significant impact on
the microstructures and mechanical properties of these alloys.
Several processing methods will be compared and contrasted and the resulting
microstructures, morphologies of the fracture surfaces, and mechanical properties
obtained from tensile testing at room temperature and up to 1927°C will be discussed.

Corr.-member of RAS A.M. Chekmarev, Prof. M. Ozawa and Prof. I.D. Troshkina
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5.3.
HETEROMETALLIC RHENIUM, NICKEL, COBALT-ALKOXIDESAS PRECURSORS FOR FUNCTIONAL MATERIALS SYNTHESIS
I. V. Mazilin, D. V. Drobot
Lomonosov Moscow State Academy of Fine Chemical Technology (Russian Federation, 119571 Moscow, Vernadsky
avenue 86)

Keywords: Aerospace superalloy, fine powder, soft chemistry, alkoxide precursor.
Abstract
New technology to obtain Re, Ni, Co hydroxides, simple and complex oxides, fine and nanosized
powders of metals and alloys has been developed. Mono- and heterometallic nickel, rhenium andcobalt alkoxides with adjustable metal content were used as precursors to produce final powders.
Electrochemical and chemical techniques for synthesis of molecularly mixed precursor compounds
were proposed. The said precursors were subjected to hydrolytic and thermal decomposition. Bychanging precursor composition and/or decomposition parameters, one can obtain powders ofdifferent size, chemical and phase composition. Ultrafine (D50=501 nm) nickel-based alloy powder
with rhenium and cobalt doping was obtained at as low as 350 °C.
Introduction
Nickel-based superalloys containing rhenium (6 - 10 %) are known to exhibit excellent mechanicalstrength and creep resistance at high temperatures, good surface stability, corrosion and oxidation
resistance [1]. They are generally applied in fields such as: aerospace, industrial gas turbine andmarine turbine industry, e.g. for turbine blades in hot sections of jet engines [1-4]. Some state-ofthe-art methods are used to produce these alloys; with all of them including melting of the metals
involved. Taking into account huge difference in the melting points of base metal (nickel, 1726 K)
and doping metal (rhenium, 3360 K), obtaining of chemically homogeneous alloy becomes anextremely difficult task. Moreover, these processes are energy-consuming because of the necessity
to maintain very high temperatures for a long time. It is of common knowledge that chemical
uniformity of precursor compound leads to a homogeneous distribution of doping elements in alloys
and general chemical composition stability. In the last decades in the context of continuous increasein energy prices, more and more attention is being paid to energy - efficient technologies. Softchemistry technique has already been applied to refractory materials and alloys synthesis [5-11]. In
the present work we have applied alkoxide route for the preparation of nickel-based alloys using
trimetallic nickel-rhenium-cobalt methoxocomplexes as a precursors.
Experimental
It is well - known that some metal alkoxides are water-sensitive and could decompose in the air;
therefore, all operations and storage of such compounds are performed in dry inert atmosphere.
The conditions of the syntheses are listed in the table 1. Individual metal methoxocomplexes wereobtained electrochemically (Syntheses I-IV). To obtain bi- and trimetallic methoxocomplexes bothconsequent anodic dissolution (Syntheses V-X) of metals and chemical reaction between individual
methoxocomplexes were applied (Synthesis XI).
The former was performed in a glass electrochemical cell with water cooling and a condenser. To
prevent the decomposition of the compounds formed the tube with drying agent (P2O5) was used.
We have used water-free methanol (Merck KGaA, purity > 99,5 %, water < 0,1 %) as anelectrolyte; a 2 cm2 platinum plate as a cathode; nickel, cobalt and rhenium plates as an anode.
Methanol was dehydrated before it was involved in synthesis by means of boiling with magnesium
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shavings followed by distillation. Water-free methanol is known to be an insulating media, for thatreason we had to use a background electrolyte – lithium chloride. Lithium chloride was annealed(180 – 200 °C) in vacuum (p ~ 1,3 Pa) for 40 – 60 minutes to dehydrate it. The concentration waschosen to be 0,025 M to provide optimal conductivity and low chlorine concentration. The process
was controlled by measuring current, voltage, temperature and anode mass loss. The consequencesof dissolution are shown in the column anode of Table 1 (“+” stands for simultaneous dissolution).
The latter involves mixing of nickel methoxide and rhenium oxomethoxide in the methanolic media
with stirring at room temperature for at least 1 hour.
Once the desired amount of metal was dissolved or the chemical reaction completed, the resulting
liquid is transferred into a glass flask and subjected to solvent vacuum evaporation to yield final
powder.
Table 1. Syntheses conditions.

#
I
II
III
IV
V
XI

U, V I, mA t, hrs
Anode#U, V I, mA t, hrs
Anode
16
45
21
Ni
7
30
40
Re - Ni
VI
16
55
7
Ni
65
60
10
Re - Ni
VII
20
65
15
Co
26
100
20
Ni - Re
VIII
31
170
16
Re
31
160
61
Re - NiIX
94025
Ni + Co
20
55
20
Re - Co - Ni
X
Chemical interaction of 100 ml 0,049 M solution I and 9,25 ml 0,054 M solution IV

The complexes obtained were analyzed by means of chemical analysis, X-Ray powder diffraction,
IR-spectoscopy, SEM and thermal analyses (DTG, TGA, DSC) in air and inert atmosphere.
Nickel was determined using titration with EDTA against murexide [12], cobalt - photometricmicrodetermination with nitroso-R salt [13], rhenium – gravimetrically as nitron perrhenate
C20H16N4·HReO4 [14], carbon and hydrogen – organic microanalysis with CHN–O–RAPID(Heraeus GmbH, Germany). X-ray diffraction patterns were obtained on XDR 6000 powder
diffractometer (Shimadzu, Japan) with Cu Kα-radiation; IR-spectra in the range 4000-400 cm─1
were taken on EQUINOX 55 spectrometer (BRUKER, Germany) between IR-transparent KRS-5
plates in liquefied petrolatum to prevent decomposition; Thermal analysis in the air was performedon Q–1500 D derivatograph (MOM, Hungary) with heating up to 430°С with 5°С/min rate.
Thermal decomposition of the complexes was accomplished in the air, argon atmosphere andhydrogen atmosphere. The quartz tube with the powders was placed in the pipe furnace. The tube
inlet and outlet were equipped with H2SO4 vessels to dehydrate argon and hydrogen. Gas flow
should be no less than 0.2 LPM. Heating rate was established to be 5°С/min, cooling rate 1015°С/min. All decomposition products were identified using XRD analysis. Particles size
distribution was determined on the Delsa™ Nano PN A54412AA analyzer (BECKMANCOULTER, USA).
Results and Discussion
At the first stage of the investigation individual nickel, rhenium and cobalt methocomplexes
Ni(OCH3)2 (I, II) Co(OCH3)2 (III) and Re4O6(OCH3)12 (IV) were obtained using anodic dissolutionof rhenium, nickel and cobalt in absolute methanol respectively. The said methoxo-derivatives werecharacterized by XRD, SEM, IR and thermal analysis.

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The XRD pattern of I is presented on the Fig. 1 withcorresponding literature data for Ni(OCH3)2 [15].
Four wide peaks at the pattern indicate that the said
compound has a distorted hexagonal layered
Mg(OH)2 structure with P3 m1 space group (cellparameters: a = 3,074 Å; c = 7,977 Å). FWHM offirst peak (2 θ = 10,89 °) was measured to be 3,092 °and according to the Debye-Shrerrer equation thecorresponding grain size is as low as 90 Å.
Complexes III, V was found to have the samestructure.
The SEM picture of I is presented at Fig. 2. It is easy
to see that average particles size is around 1 µm. The
difference in calculated and visible sizes of particles
can be explained by a strong tendency fornanoparticles to agglomerate.
The IR-spectrum of I contains methoxo–derivatives
ν (С-О) intrinsic peak at 1073 cm-1 and few peaks inthe metal-oxygen region: ν (Ni–O(R)–Ni) at 631 cm1and ν (Ni–O(R)) at 454 and 408 cm-1, with theformer intensity being twice as great. There is also a
weak peak at 3294 cm-1 correlated to ν (О-Н) ofabsorbed methanol. According to the IR spectrum,
Ni(OCH3)2 has a continuous structure with Ni–
O(R)–Ni bridges. The IR spectra of III are almost
alike: ν (С-О) at 1066 cm-1; ν (Co–O(R)–Co) at
606 cm-1; ν (Co–O(R)) at 450 cm-1.
The thermal decomposition mechanism in the air
and inert atmosphere was studied by means of
DTA/DTG
andDSC/DTG
techniques
respectively. The DTA/DTG curves of I are shownat Fig. 3. At the initial stage of heating in the air(below 100 °C) absorbed methanol evaporation istaking place followed by partial evaporation ofligand (up to 195 °C); the thermal decompositionof I in the air begins at around 235 °C. According
to the DTA peak, the final product (NiO) starts tocrystallize at 255 °C. The thermal
decomposition of III in the air begins
at 185 °C with the formation of CoO
followed by oxidation to spinel Co3O4
at 235 °C.
The thermal behavior of I in the inert
atmosphere deviates slightly. The
thermal decomposition begins at
210 °C and ends at 270 °C with the
crystallization of NiO; On thecontrary, the DSC curve of III
contains exo-effect at 307 °C and thefinal product is CoO (instead of Co3O4
in the air). The XRD pattern, theFig. 1. XRD pattern of I (top) and data for
Ni(OCH3)2 [15] (bottom).

Fig. 2. SEM picture of I.

Fig. 3. DTA/DTG curves of I.

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crystal structure, the IR spectrum and the thermal analysis of IV were reported by our colleagues [8,16].
The hydrolytic decomposition of I-III leads to the formation of nickel and cobalt hydroxides withthe same structure and a slightly larger grain size determined from Debye-Sherrer equation (140 Å
in case of I).
At the second stage of our investigation bi- and trimetallic nickel-rhenium methoxodervatives wereobtained and analyzed. The XRD analysis has shown that compounds X, XI with low rhenium havethe same structure as I. Bimetallic compounds VI-IX with high rhenium are X-Ray amorphous. The
results of the chemical analyses and the IR-spectra peaks positions are shown in Table 2.
Table 2. Chemical compositions and IR-spectra peaks of heterometallic complexes.

#

Ni, wt % Re, wt %

VI
VII
VIII
IX
X
XI

31,83
14,71
10,76
6,80
33,51
45,41

19,61
37,14
51,01
57,13
14,21
14,70

FormulaNi5.4Re1(OCH3)8
Ni1.3Re1(OCH3)5
Ni1Re1.5(OCH3)4
Ni1Re2.7(OCH3)4
Ni8Re1Co0.1(OCH3)14
Ni9.8Re1(OCH3)10

Positions of IR peaks, cm-1
ν (С-О) ν (Ni–O(R)) ν (Re–O(R))
1041
640w, 457 909, 550, 418
1039
639, 458
908, 527, 424
1050
652, 465
907, 523, 431
1058
654, 465
934, 530, 425
1045
640w, 456 916, 553, 420
1049
640w, 455 913, 548, 422

It leads us to a supposition that compounds VI-XI do not have direct nickel-rhenium bond, but these
metals are linked by means of oxygen or oxygen-ligand bridges. Having compared the obtained IRspectra for VI-XI with the ones for I-IV, we determined a shift in the peak positions. This can beused as the evidence of molecularly mixed nickel rhenium precursor compounds formation.
The
thermaldecomposition
mechanism of VI-XI in the air isdetermined from DTA/DTG curves.
The DTA/DTG curves of X are shownat Fig. 4. Gradual evaporation of theabsorbed methanol and some part ofthe ligand gives way to the final
decomposition at 210 °C. Even low
rhenium content in the bimetallic
complex X leads to multistage productcrystallization (the main DTA peak at
245 °C is followed by another three).
Fig. 4. DTA/DTG curves of X.
Additional studies are required todetermine all the intermediates.
All the collected data involving the composition, the structure and the thermal properties of the
precursor compounds allowed us to develop a technology to carry out the synthesis of functional
materials. Depending on the thermal decomposition conditions we can obtain fine or evennanosized powders of nickel, rhenium and cobalt oxides, hydroxides or alloys with any desirable
metals content. This ratio can be set at the precursor synthesis stage and remains almost constantafter thermal treatment. All the decomposition products we have obtained are summarized inTable 3.

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For instance, let us discuss the case of nickel-rhenium-cobalt alloy powder synthesis with content ofmetals close to that in aerospace superalloys. The precursor compound X with adjusted content ofmetals was thermally threated at 350 °C for 2 hours in the hydrogen atmosphere to produce the final
powder (its size distribution and the XRD pattern are shown at Fig. 5 and 6) respectively.

Fig. 5. Particles size distribution of X
decomposition product in hydrogen.

Fig. 6. XRD pattern of X decomposition
product in hydrogen (top) and data for Ni
ICDD card # 65-0380 (bottom).

The average size of particles is D50 = 501 nm and we believe that it can be decreased further bymeans of changing decomposition conditions. The Ni-based solid solution (sp.gr Fm3m,
a = 3,570 Å) obtained has slightly shifted the XRD peaks indicating the presence of rhenium andcobalt. The rhenium content can be estimated as 14 wt.% according to the cell parameter and thedata cited in literature [17].
It is obvious that methoxo-derivatives can be effectively applied as precursors to obtain metals,
alloys, ceramic powders and, potentially, coatings by means of the CVD technique.
Table 3. Precursor decomposition products obtained (*TBD - to be defined).

Precursor compound
Ni(OCH3)2
Co(OCH3)2
Re4O6(OCH3)12
NiXCoY(OCH3)N

Hydrolysis
products
Ni(OH)2
Co(OH)2
TBD*
x Ni(OH)2y Co(OH)2

NiXReY(OCH3)NTBD*

NiXReYCoZ(OCH3)N

TBD*

Thermal decomposition products
In airIn inert gas
In hydrogen
NiO
NiO
Ni
Co3O4
CoO
Co
ReO3, Re3O10
ReO2
Re
NiCo2O4, x NiO,
x Ni-y Co solid
xNiO·yCoO
y Co3O4
solution
NiReO4, x NiO,
x Ni-y Re solid
TBD*
y ReO3solution
NiReO4, x NiO,
x Ni-y Re-z Co
TBD*
y ReO3, v Co3O4
solid solution

Conclusions
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The alkoxo-technology has been proved to be an effective method for the Ni-Re-Co alloy fine
powder synthesis with adjustable content of metals (RU 2010132289 Pat. Appl.);Variations in alkoxide decomposition parameters made it possible to obtain simple and complex
oxides, hydroxides and alloy powders, fine and nanosized;
Thermal properties of nickel and cobalt methoxocomplexes were investigated;
The heterometallic Ni-Re and Ni-Re-Co methoxocomplexes were obtained for the first time ever,their properties are being investigated.
Anknowledgements: Yuri V. Syrov and Yuri V. Velikodniy – XRD Analyses; Elena E. Nikishina– DTA Analyses; Sergey Savilov – DSC Analyses; Valeri V. Kravchenko – IR Spectra; Tatiana E.
Yakovleva – English translation. Work granted by RFBR (projects 06-03-32444 and 09-03-00328).
References
1. B. Geddes, H. Leon, Xiao Huang; Superalloys: Alloying and Performance ASM
International, 2010, 176 pp.
2. S. Walson, A. Cetel, R. Mackay, O. Hara, D. Duhl and R. Dreshfield; Joint Development ofa Fourth Generation single Crystal Superalloy. NASA TM–2004-213062
3. E.N. Kablov, N.V. Petrushin, I.L. Svetlov, I.M. Demonis, Technology of light alloys, 2: 6-16
(2007)
4. R. H. Tuffias, R. B. Kaplan, and M. A. Appel. Proc. Int. Symp. Rhenium and Rhenium
Alloys Orlando, USA, 10—13 February, TMS, 1997, p.275
5. N. Ya. Turova, E. P. Turevskaya, V. G. Kessler, and M. I. Yanovskaya; The Chemistry of
Metal Alkoxides, Kluwer Acad. Publ., Boston—Dordrecht—London, 2002, 568 pp.
6. D. Drobot, G. Seisenbaeva, V. Kessler, P. Scheglov, O. Nikonova, S. Michnevich, O.
Petrakova, Journal of cluster science, 20:23-36 (2009)
7. P. A. Shcheglov, D.V. Drobot, Russian Chemical Bulletin, 54: 2247-2258 (2005)
8. P. A. Shcheglov, PhD Thesis, Moscow, 2002, 198 p.
9. P. A. Shcheglov, D. V. Drobot, Inorg. Mater., 40:176 (2004)
10. P. A. Shcheglov, D. V. Drobot, G. A. Seisenbaeva, S. Gohil, and V. G. Kessler, Chem.
Mater., 14:2378 (2002)
11. I. V. Mazilin, Rhenium, nickel and cobalt alkoxides as precursors for functional materials
synthesis, Master’s thesis, Moscow, 2009, 113 p.
12. H. Flaschka, G.Schwarzenbach, Complexometric titrations, London: Methuen, 1969, p.244248
13. S. Baybaeva, L. Krylova, Methods for paint coatings analysis, Chemistry, Moscow, 1974,
324 pp.
14. V.F. Hillebrad, H.E. Lendel, G.A. Bright, A Practical Guide to Inorganic Chemical
Analysis, Chemistry, Moscow, 1966, p. 372-381
15. Rogova T.V., Turova N.Ya., Zhadanov B. V., Coordination chemistry, 11:784-788 (1985)
16. A. I. Ermakov, V. V. Belousov, D. V. Drobot, P. A. Shcheglov, Coordination Chemistry,
32:701–706 (2006)
17. A. Nash, P. Nash, Bulletin of Alloy Phase Diagram, 6:348-350 (1985)

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5.4.
METALLOTHERMIC METHOD FOR PRODUCINGRHENIUM-BASED ALLOYS
A.P. Parshin1, R.N. Manuylov1, S.A. Melnikov1, G.M. Voldman2
1. Public corporation «Leading research institute of chemical technology»
33, Kashirskoye shosse, Moscow 115409, Russia, info@vniiht.ru
2. Lomonosov Moscow State Academy of Fine Chemical Technology
86, prospect Vernadskogo, Moscow 119571, Russia, mitht@mitht.ru

The aim of this work was to design a technology for producing rhenium alloys withlow carbon content (<0,05 % of the mass) by metallothermal method.
The initial mixture components such as ReO2; CaMoO4; NiO and PA – 4 (Aluminium
powder) as a reducing agent were used to obtain the master-alloy based on rhenium.
ReO2 was produced on automated plant VME-8-10,5 by thermal decomposition ofammonium perrhenate in argon atmosphere. Direct metal yield achieve 95,3 %.
Calcium molybdate (technical standards 48-3812-28-87), nickel oxide (GOST (state
standard) 609-4125-75), AP – 4 (Aluminium powder) aluminium powder (GOST (state
standard) 6058-73) were used in this research. Inert additive of calcium oxide was applied
to reduce thermal effect of the reaction.
To study metallothermic processes of obtaining rhenium alloys a variation content ofinitial mixture components m(ReO2) : m(CaMoO4) : m(NiO) in the range from 1 : 0,298 :
0,125 to 0,457:0,197: was conducted, and also the effect of reducing agent excess from 0%
to 20% was studied.
The results of the experiments have shown that the optimal compounds mixture was of
1 : 0,38 : 0,155, and percentage of aluminum excess varies from 7 to 10 % of the mass. In
this case ingot extraction amounts to 95,3%.
Due to slag processing and extraction of supplementary metallic phase ingot extraction
can be increase to 98%.
There was produced an enlarged batch of master-alloy that fully met the requirementsof technical standards 1-92-202-2001.

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5.5.
RHENIUM EFFECT IN Mo-Re WELDS
F. Morito (a), M.I. Danylenko (b) and A.V. Krajnikov (b)(a) MSF Laboratory, Moriya, Japan(b) Institute for Problems of Materials Science, Kiev, Ukraine

Rhenium is widely used to alloys VIA group refractory metals. In particular, the strength andplasticity, creep resistance, and low temperature ductility of Mo are all improved with increasing
the rhenium content due to the so-called “rhenium effect”. In addition to traditional applications,such as heating elements, electron tube components, etc, Mo-Re alloys are considered as candidate
materials for structural applications for chemicals and energy facilities, including elements of fusion
or fast breeder reactors. Welds are obligatory elements of practically any complex construction
while working conditions are characterized by high temperatures (>1000 K), aggressive medium(liquid metals) and high neutron fluence (>1021 n/cm2).
Therefore, good weldability, high radiation performance, thermal stability and corrosion
resistance are the key issues for these application fields. Tendency of Mo alloys to embrittle at low
temperatures assumes probable degradation of the mechanical properties either during welding or
under irradiation. In spite of the fact that significant progress has been achieved in studying themechanism of rhenium effect, many details of Mo-Re alloy behaviour under extreme operating
conditions are not studied yet.
This work analyses several Mo-Re alloys and welds with the Re content 0-50% in as-received
state and after electron beam welding and/or radiation treatment. The mechanical properties andmicrostructure of Mo-Re welds are examined focusing on the effect of Re concentration. Phasestability, microstructural changes and impurity redistribution are studied for better understanding
and predicting the long-term performance of Mo-Re alloys at high temperatures and/or high neutron
fluences.
In particular, a strategy of welding of Mo-Re alloys is discussed with emphasis on thesensitivity of alloys to pre-weld heatings and on the development of post-weld treatments, such as
warm rolling and annealing, to provide optimal phase composition. Grain refinement during
directional solidification after welding, ductility improvement and fracture mode change fromintergranular to transgranular one are clearly observed with an increase of Re content.
Effect of neutron irradiation on the strength of Mo-Re welds is studied for a wide temperature
range. Mo-Re welds exhibit a large radiation-induced strengthening. At room temperature, thestrengthening effect is rather limited and unstable because of lack of ductility. The strengthening
becomes strongly pronounced at high temperatures. Damaging effect of neutrons at hightemperatures is shown to be smaller than that at low temperatures. Intensification of homogeneous
nucleation of Re-rich sigma phases in all studied Mo-Re alloys is observed after high temperatureneutron irradiation. As a result, all parts of as-irradiated welds display approximately same level ofstrength.
High-temperature annealings with different heating/cooling rates have been used to simulate
thermal conditions in different welding zones. Impurity redistribution in Mo-Re alloys has beenstudied by surface analysis methods. The role of carbon and oxygen segregation as well as
formation of carbides and Re-base phases is discussed to minimise intergranular embrittlement ofwelds.

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5.6.
USE OF TUNGSTEN AND RHENIUM ALLOYSFOR MANUFACTURING OF HIGH-TEMPERATURE
THERMOCOUPLES W5%Re/W20%Re
P.P.Oleynikov, P.A.Zaytsev, A.A.Ulanovskiy1, S.N.Nenashev2, T.Ju.Goncharuk3

Scientific Industrial Association (SIA) "LUCH” (Zhelesnodorozhnaya, 24, Podolsk, Moscow region, RussianFederation)
1- Obninsk Thermoelectric Company (OTC), Ltd. (Lenina,121, Obninsk, Kaluga region, Russian Federation)2- Federal State Institution "ROSTEST-MOSKVA ("Nahimovskiy pr.,31, Moscow, Russian Federation)
3- Company "Volfram", Ltd. (Bozovaj st.,7, Moscow, Russian Federation)

Keywords: tungsten and rhenium alloys, thermocouple, thermoelement, thermoelectriccharacteristics, electromotive force, EMF, standard specimen, calibration uncertainty, disperse
hardening, nanoparticles.
Abstract
Features of development in Russia and application of thermocouples with thermoelements made oftungsten-rhenium alloys are briefly characterized in the paper. The choice of alloys with therhenium contents 5 and 20 % is justified [1].
At present time systematic researches of W-Re thermocouples in the range of temperatures 2000 ...
2500 °C are necessary. In this range the following factors are very essential: EMF drift ofthermocouples, signal shunting through insulating armature, compatibility of materials at hightemperatures. Commonly approved calibration procedure of thermocouples also needs to be
developed for this range of temperatures. To increase stability of thermoelectric materials thepossibilities of nano-technologies and disperse hardening of alloys should be considered.
Introduction
Thermoelement materials for W-Re thermocouples are produced by a method of powder
metallurgy. Powders of tungsten and ammonium perrhenate (NH4ReO4) are preliminary mixed,
and then the mixture is pressed into cylindrical columns and melted. The columns are forged anddrawn into a wire of diameters varied from 0,5 to 0,1 mm. Finished wire is subjected to stabilizing
annealing in hydrogen.
The research stage in Russia had been finished by 1977 when technical Specifications on
manufacture of thermoelement materials [2] was developed at MELZ (Moscow electric bulbs plant)
and the reference table of the thermocouple [3] was standardized. Reference table included in
GOST 3044-77 contained three close graduations: А-1, А-2, А-3. Last two graduations lay aboveand below the basic graduation А-1. Their upper limits had been limited by 1800°С, and the basic 2500°С.
The temperature range 0…1800°С is inherent for the gages which are widely applied in metallurgy
for short-term temperature measurements of liquid metals [4]. The temperatures closed to upper
limit were often realized in nuclear and space industries, and also while carrying out of hightemperature scientific researches [5].
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According to the national verification scheme (GOST 8.558-93) standard thermoelectric
thermometers based on W-Re thermocouples had been developed to transfer temperature unit in therange 900...2500 °C to industrial thermoelectric thermometers. To certificate W-Re wires the Ural'sInstitute of Metrology (Ekaterinburg, Russia) had developed and introduced into metrologicalpractice standard specimens of thermoelectric materials (SOTM) (wires) for
W-Re5 and W-Re20 alloys. They were calibrated with expanded uncertainty about 11 °C at thetemperature 2500 °C by a "wire bridge" method [6].
Unfortunately, in 1990-s consumption of W-Re thermoelectric wires was sharply reduced becauseof falling of industrial production in Russia. Production of tungsten and rhenium wires at MELZ
became spasmodic and eventually had been stopped. It took several years for manufacture
restoration (at “Rhenium” company, Ltd.). The company could keep invariable both manufacture
processing methods, and procedures of certification and selection of alloys for thermocouples.
The present stage of development of high-temperature thermometry is connected with creation of a
new generation of installations having limiting parameters. New researches have sharply expanded
the nomenclature of high-temperature materials investigated and increased quantity of controllable
high-temperature technological processes [7].
The requirements to control high temperature of a technological process have become more severe
and they demanded new quality of certification of high-temperature technological and test
equipment.
For the decision of the arisen measuring problems high-temperature thermoelectric converters(thermometers) were required with greater number of running cycles while realization oftechnological control. Also they had to guarantee reliable information on temperature regimes underoperation of autonomous installations. The set life-time figures for most of them consist 5 and more
years.
By this time manufacturers succeeded to find the ways of essential increase of working resource
stability for high-temperature thermometers. Placing their sensitive elements in gas-tight protective
tubes filled with neutral gas, working capacity of a measurement device had been provided at thetemperatures up to 1800°С both in air and neutral environments during many thousands hours. Suchdesigns with sapphire and molybdenum protective tubes are described in [8,9].
The increased interest to similar developments lead to the decision of international working group
N5 of IEC SC65B to include tungsten-rhenium thermocouple of types A (W-Re5% / W-Re20%)(Russia) and C (W-Re5% / W-Re26%) (USA) and their reference tables to a new draft of thestandards IEC60584-1 and 2.
As a result of this decision the demand for reproducibility check of thermoelectric characteristics oftype A thermocouples produced now in Russia was made. Also it was necessary to check thepossible improvements of their metrological stability by modifying of a positive electrode bydisperse hardening method. Oxide particles aggregated with alkaline additives entered into initialfusion mixture as it was described in [10].
The similar stabilizing effect was fixed in refractory metals in case of allocation different nanoparticles on grain borders of metal. In [11], for example, stabilization of tungsten composite
structure was fixed to temperatures 2200-2400°С.
Experimental
After W-Re thermocouples of types A (W5%Re/W20%Re) and C (W5%Re/W26%Re) including
into the new draft of IEC standard 60584-1 and 2 Russian researches had to check reproducibility ofthermoelectric characteristics for type A thermocouples manufactured now in Russia. The
calibration program and comparison of calibrations results were performed by Russian metrologists(ROSTEST-MOSKVA; VNIIM, OTC, SIA"LUCH") and experts of foreign research laboratories(PTB, Germany; NIST, USA; NIMJ, Japan; NRC, Canada). All participants investigated thethermocouple specimens made of the same pairs of wire coils having diameters 0.5 and 0.35 mm.
The Russian researchers realized calibration of W5%Re/W20%Re thermocouples in the range of
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temperatures 600 ... 2500°C by various methods. There were performed "wire-to-wire" comparisonof the tested specimens with standard W-Re wires and comparison of W-Re thermocouples with areference type B thermocouple or a reference pyrometer. In all range of temperatures calibrations
data were within 0.7 % limit of permissible EMF deviations from reference table according to
Russian standard GOSTR 8.585-2001. New draft of IEC standard installs the limit of permissible
deviations ±1 %. The results of researches well agreed with the results of foreign participants of the
project in the investigated temperature range (600... 1850 °C). New draft of IEC 60584 standard has
been fully agreed and in the nearest future it will be transferred for voting to National Committeesof the countries - IEC participants [12].
For estimation of prospects of thermal stabilization of a positive thermoelement of type A
thermocouple there was manufactured an experimental wire of 0.35mm in diameter, containing 0.1% (weight) nanoparticles of yttrium oxide with average size 50 nanometers. Nanoparticles werereceived in scientific research institute of inorganic materials (Moscow) and were added to initialfusion mixture by the way similar to one described in [10].
Results and Discussion
The following characteristics as thermoelectric uniformity, durability, microhardness (530-540
kg/mm2) of the newly received composite practically didn't differ from the values defined for thealloy WAR5 in the work [10]. Microstructures of initial materials were also similar.
Results of electronic microscopy testify that under plastic deformation there is intensive
stratification of the material on grain borders and destruction of separate grains in planes ofcleavage.
As for the thermoelectric characteristics, the first calibration of an initial alloy against
corresponding standard specimen (SOТМ) executed before and after 30-minute annealing at
1650°С have revealed negligible difference in behavior between direct and reverse calibration
curves in each heating-cooling cycle. But there was essential discrepancy in the results of different
cycles (Fig.1). It can be explained by insufficient stabilization of initial alloy structure during
unitary annealing of the wire at 1500°С under manufacturing process.
The results received under the subsequent cyclic annealings at 1700°С have confirmed thisconclusion. In these experiments the wire cut from regular W-Re20 coil was used as reference
thermoelement. Fig.2 shows EMF changes of the thermocouple in three consecutive cycles ofheating and cooling after annealing at 1700°С during 4, 5 and 2 hours.
It is obvious that EMF of the thermoelement investigated stabilized only after the second cycle oralmost 10 hour annealing. In the last cycle direct and reverse curves have practically coincided
taking into consideration the fact that measurements uncertainty in this case, according to [12], wasnearly ±4°С.
It is interesting to trace the EMF variation during high-temperature annealing. As it is shown in
Fig.3, during the first hours the working signal of the thermocouple decreased with the rate almost
coinciding with earlier observed EMF drift for WAR5 alloy in [13]. After the second cycle thecharacteristic was restored, practically, to initial level.

390Нижние - после первого короткого отжига при
1600, верхние - после отжига 30 мин при 1650th

7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

ΔЕ, mV

0,08

Curve
Ряд11

0,06

Ряд2

Curve 2

0,04
0,02

Ряд3
Curve
Ряд43

0

Curve 4-0,02 0

500

1000

1500

°С
2000

-0,04
-0,06
-0,08
Fig. 1 EMF changes for nanostrengthened termoelement W-Re5% against SOTM wire while calibrations ofinitial wire and the wire after 30-minute annealing at 1650°.
Curves 1 and 2– heating and cooling of initial wire,
curves 3 and 4 – heating and cooling of the wire after half-hour annealing at 1650°С.

32Cycle 1
Cycle 2

1

Cycle 3Fig. 2 EMF changes of W-Re5% (0,1% of nanoparticles of yttrium oxide) against W-Re20% (coil 311)
thermocouple during three consecutive cycles of heating and cooling.

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Fig.3 EMF change for W-Re5% (0,1% of nanoparticles of yttrium oxide) against W-Re20% (coil 311)
thermocouple relatively initial value observed in the first cycle.

Annealing of experimental thermocouple at 2000°С according to the received results (Fig. 4) led tomuch faster stabilization of the composite. In this case EMF deviations from nominal values areshown for direct and reverse (after an hour annealing) calibration curves.

Fig.4 EMF deviation from nominal values for W-Re5% (0,1% of nanoparticles of yttrium oxide) against
SOTM wire during heating-cooling cycle with an hour annealing at 2000°С.

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Conclusions
Despite certain convention of such conclusions, essential stabilization of the composite structure is
obvious fact that allows optimistic estimations regarding continuation of the researches ofthermoelectric properties of nanocomposites. They will allow improving of the next generation ofhigh temperature standard specimens of thermoelectric materials.
References
1. S.K.Danishevsky, A.N. Gurevich, N.I.Smirnova, E.I.Pavlova. Thermocouples for hightemperature measurements having thermoelements on the base of molybdenum or tungsten. AC
USSR №108438, Bulletin of inventions, 4 (1958).
2. SUO.021.142 TU. The annealed wire made of tungsten and rhenium alloy and graduated forthermoelements of thermocouples. Specifications (1976).
3. Thermoelectric converters. Nominal static characteristics of transformation. SU Standard GOST
3044-77, Moscow, Standards Publishing House, (1977.)
4. О.A.Gerashenko, А.N.Gordov, V.I.Lah. Temperature measurements. A guide. Kiev, Naukova
dumka, p.494 (1984).
5. I.I.Fedik, V.P.Deniskin, V.I.Nalivaev, V.S.Konstantinov, The problem of high temperature
measurements in fuel assemblies of nuclear propulsion engines. J. Devices and automation, 3 (21):20-27 (2002).
6. Methodical instructions. State System of Measurements. Standard specimens of properties ofthermoelectric materials made of W-Re5 andW-Re20 alloys (SOTM W-Re5/20). MI 1745-87.
7. P.А.Zaytsev, P.P.Oleynikov, А.А.Ulanovskiy, S.N.Nenashev Abstracts of 5th International
conferences «Power saving up technologies in the industry», September 27-30, 2009. Pp.3-17.
8. V.B.Pampura, V.А.Povalyaev, P.P.Oleynikov, А.G.Hotkin, J.New industrial technologies, 6: 6163 (2007)
9. А.А.Ulanovskiy, B.L.Shmiryov, Y.N.Altuhov, Devices and automation, №5(71): 4-13, (2006.)
10. P.P.Oleynikov, V.I.Nalivaev. Issues of a nuclear science and technics. Nuclear materials
technology. Moscow, VNIINM, 5, p.97 (1982).
11. S.V.Alekseev, А.А.Pavlov, M.L.Taubin, А.А.Yaskolko. Abstracts of international conference«Nanotechnology of functional materials», S.-Petersburg, Pub. GPU, p.165 (2010).
12. А.А.Ulanovskiy, V.А. Medvedev, S.N.Nenashev, Y.А.Sild, M.S.Matveev, А.I.Pokhodun, P.P.
Oleynikov, Int. J. of Thermophysics, 31: 1573-1582 (2010).
13. S.K.Danishevsky, L.D.Oleynikova, S.I.Pavlova, L.I.Trahtenberg, P.P. Oleynikov. Rhenium in
new technics, Science Pub., Moscow, 190-193 (1970).

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5.7.
MODERN STRUCTURAL MATERIALS BASED ON THE
W-Mo-Re SYSTEM
Povarova K.B, Kazanskaya N.K.
Baykov Institute of Metallurgy and Materials Science RAS povarova@imet.ac.ru

The high-rhenium alloys, based on the bcc Group VI metals of the periodic table (Wand Mo) are known. These alloys exhibiting the “Re effect-1” (a simultaneous increase in
low-temperature ductility and strength of Group VI metals after the addition of 25-35 at. %Re connected with an additional deformation mechanism by twinning) are lied near theα(W,Mo)/α+σ interphase boundary.
These high-rhenium alloys are as good as W and Mo alloys in high-temperaturestrength, but, unlike them, are not cold-brittle and do not become embrittled after hightemperature service and thermal cycling.
The binary W-Re, Mo-Re and ternary W-Mo-Re alloys have satisfactory formability
and can be produced both as bulk articles and structures and as micron-scale semiproducts(foil, wire), which cannot be produced from Re because Re is expensive metal anddemonstrates poor deformability caused by intense strain hardening.
The manufacture of the alloys by vacuum melting (VM) provides a high purity relative
to interstitial impurities and a homogeneous Re distribution. This prevents the σ phaseformation (deteriorating the plasticity), promotes the deformability, and allows the realizationof “Re effect-2” (an abrupt increase in the strain hardening rate of W and Mo alloys due to the
Re addition, up to B = 4500-6000 MPa for micron-scale wire).
Such micron-scale wire from alloys of the MRe-47VM type retain the ability to
deformation by flattening and to spiral coiling. In the case where high-rhenium alloys are
manufactured by the cheaper PM method, none technique of the Re introduction into theinitial powder provides a uniform distribution of Re, whose segregates provoke the formationof grain-boundary σ-phase precipitates. Therefore, the Re content in the PM alloys is smaller
than in the VM alloys (WRe20PM//WRe27VM and MRe40PM//MRe47VM).
The investigation of the effect of Re on the electronic structure, physical andmechanical properties of W and Mo have revealed the “Re effect-3” (a substantial increase in
low-temperature ductility of W and Mo alloys at 2-7 at. % Re).
This allowed the development of low-rhenium high-temperature W-Re alloys for bulk
products, including those reinforced by refractory MeC-type carbides and Y2O3-type oxides
for massive parts of the structures operating at temperatures above 2000ºC.

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5.8.
TECHNETIUM - A RARE METAL PRODUCED BY MAN FOR
STRUCTURAL AND MEDICAL USE
Edwin D. Sayree-mail: pbmpilot@comcast.net

Abstract
Technetium-99 is a manmade element made for medical and high temperature structural use.
Technetium is too rare in nature for any use so it is made as Tc99m with short half life for medical
use and Tc99 with long half life and low beta radiation for structural use is provided by the fission
products in used nuclear fuel. The needed Tc99m for medical use is produced by radiation ofmolybdenum with nuclear reactors. The Tc99 metal with very much longer half life and lessradiation is separated from the spent nuclear fuel, reduced and purified to pure metal powder andmelted to ingots. Technetium has physical properties very similar to Rhenium. Technetium-99 was
taken from the waste tanks in Hanford, Washington, purified, reduced to metal powder and melted
into an ingot programmed by the author in 1964.(1) The Tc99 was then used to alloy with tungsten
to improve its ductility similar to rhenium. The tungsten alloy with 25% technetium could be cold
forged indicating the improved ductility. The current nuclear power plants produce about 800 gramsof technetium per metric ton of used nuclear fuel. The commercial value of the technetium
produced by a 1000 megawatt reactor in one year is about $240,000 assuming the value of Tc99
equal to that of rhenium. Almost all of the literature on technetium is about the medical Tc99 since
there has been very little removed from used nuclear fuel fission products. The author also had
Tc99 inserted to locate cancer cells to be irradiated for destruction. It was successful ten years ago.
The value of technetium will help pay for the reprocessing of used nuclear fuel around the world.
Preface
There are several purposes to write this paper on technetium. Moet people have no knowledge
whatsoever of technetium99. Most of the public papers are written about the element with the very
short half life used for medical purposes. The author wrote a paper on technetium for theInternational Symposium on Rhenium and Rhenium Alloys on technetium recovered from thefission products in used nuclear fuel. This provided the opportunity to cover both the medical
Tc99m and the high temperature structural Tc-99. Both of these applications will be covered in thispaper.
Introduction
Technetium has many properties similar to its sister element rhenium. In 1925 Noddack, Tacke andBerg announced the discovery of the element 43 by X-ray emission spectroscopy on theconcentrated sulfates of niobium and platinum. The occurrence of technetium in nature is
extremely rare. The first manmade technetium99 was made in 1937 by Perrier and Serge at
Berkeley by irradiating molybdenum with neutrons.
As far as is known the first technetium-99 was taken from used nuclear fuel by a program
developed by the author and funded by NASA in 1963 at the Hanford Laboratory in Washington
state.. The author became interested in technetium in the early 1960s while developing advanced
high temperature alloys for jet engines at General Electric. Rhenium was just being introduced andit was found that technetium is a similar element and could also improve high temperature
properties of cobalt and nickel alloys for turbine blades.
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Figure 1. Technetium ingot being inspected

The author then found that technetium did not exist. He was then moved to Hanford and found that
there was much technetium in the so-called waste tanks. That is when the program was established
to remove technetium from the waste, reduce it into metal powder and then arc melt it into an ingot.
The program continued to alloy the technetium with tungsten to see if it improved it’s ductility likerhenium does. Alloys of tungsten with 10%, 15%, 20% and 25% technetium were vacuum arc
melted and cast into small test ingots. The test ingots were evaluated and the tungsten 25%
technetium was determined to be ductile.
There was a little work just beginning on developing the 99Tc with the high radiation and short halflife from irradiating molybdenum. It is now in very much demand for medical testing to locate andevaluate various cells in the body. The author had it used to locate cancer cells that escaped fromhis prostate cancer before it was removed. Then high level radiation was used to destroy the cancer
cells located by the 99Tc. It proved to be a very good medical tool to keep the author going into his
middle eighties.
The Production of Technetium Metal for Structural use From Used Nuclear Fuel
The only source for production of technetium metal for metallic use is used nuclear fuel. The
average production of stable technetium metal for structural use is about 800 grams per metric ton
after use for one year. It is one of the useful fission products. If the technetium has the same value
as rhenium then the value of the amount per metric ton of used fuel is about $8,000. The value ofthe amount of technetium produced each year from a 1,000 megawatt nuclear plant is $240,000...
Right now the amount of used nuclear fuel being stored in the US is about 64,000 metric tons. This
contains about 50,000 kilograms of technetium worth about $51,000,000. In addition to thetechnetium there are some other very valuable fission product metallic elements.
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There is some advantage to storing the used nuclear fuel for about 50 years before separating out
the fission products and the actinides. When the used fuel is first taken out of the reactor there aremany fission products and actinides that have very short half lives with high level radiation. Byleaving these storing for 40 to 60 years they have gone through many half lives. Which means they
have only very long half lives and the very low level of radiation left.
Technetium-99 when it is created it has a half life of 6.01 hours and it radiates gamma at 0.14051
and beta at 0.347. After the radiation age change to 99Tc it has a half life of 2.13 x105a or 213,000
years. It has very low radiation danger unless it is located internally. There is some 97Tc and 98Tc in
the fission product technetium but there is no certainty of the amount yet. But it is estimated thatthey are a very small percentage. The different isotopes of technetium are shown in Table 1.
The process to separate the technetium from the fission product solution is to provide an element to
get the technetium to precipitate and get separated from the solution. It is then reacted to purify it
into ammonium pertechnate. It is then reduced in a hydrogen furnace to pure technetium powder.
The powder is pressed into electrodes and vacuum arc melted into ingots. Then the technetium canbe alloyed with other metals.
Technetium can be alloyed with tungsten to improve its ductility. Very small additions oftechnetium to steel tend to improve its corrosion resistance.
Very small additions of technetium in nuclear grade stainless steel may have a significant
improvement in radiation assisted stress corrosion cracking.
Technetium may have the same improving effect as rhenium in high temperature jet engine alloys.
Because of its characteristics as technetium gets available it will see broad usage.
Developing the Sources of Technetium
With advanced separation processes for the fission products from the used nuclear fuel there should
be adequate technetium available. There are such large quantities of valuable fission products
available that their value will make their production very cost effective. The following tables show
the amounts and value of most of the usable fission products.
Table 1 Technetium for Commercial Use

Isotopes Amountgr.

Half life
Years

Radioactivity
Mev

Commercial Value
1 Metric ton Used fuel fromof used fuel 1000 MW Nuc.
___________________________________________________________Plant for 1 Yr.
Tc98
0.006
4.2E6
β 0.40, γ 0.7454
Τc99
770
2.3E5
β 0.293 γ 0.090
Total
771
$7710
$239,859
Table 2 Natural Elements with Stable Isotopes

Isotopes AmountGr.

Half life

Radioactivity
Mev

Commercial Value
1 Metric ton Used fuel fromof used fuel 203 reactors in___________________________________________________________the year 2050
Bromine21.6
stablenone$
22$50,600
Molybdenum 3,345
stablenone
860
1,978,000
Ruthenium 2,177
stablenone
99,663229,220,000
Silver
76.2
stablenone
152349,600
Cadmium
107.8
stablenone
215
494,500
Barium2,311
stablenone
1,295
2,978,500
Terbium
2.6
stablenone
78
179,400
Dysprosium
1.4
stablenone
7
16,700Rhodium
467
stablenone
233,500
537,050,000
Total
8,509.6$335,792$772,320,000
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Table 3 Natural Elements with Radioactive Isotopes
Element

Amountgr.

Radioactive Isotope
Commercial Value
Isotope Percent Half Life Radioactive 1 Metric ton Used fuel fromMev
of used fuel203 reactors in___________________________________________________________________ the year 2050__

Rubidium365
Tellurium
484.58Lanthanum 1215
Neodymium 2803.2
Indium
Cerium
Τοταλ

2.6
2,355
7,225.38

Rb87
66.8
4.89E10 β 0.273, no γ $ 4,300
Te123
0.0017 1.3E13
e?
675
La138
0.0004 1.05E11 β0.26, γ 1.44
2.187
Nd144
0.65
2.1E15α 1.83
6,166
Νd145
0.24
>6E16
α?
In115
92
4.4E14 β 0.48
26
Ce142
47.
5E16a
α~1.5?
662$7,850$9,890,000
1.552, 500
5,030,100
14,177,200
59,8001,522,600$18,055,000

There are several usable fission product metals not listed here. Half the fission products in usedfuel that has been aged over 50 years is not radioactive and about half of the other half is so low inradioactivity that it can have good usage Most of the countries that are reprocessing used nuclear
fuel are just storing the fission product solutions with the plan to separate them later.

Figure 2 Technetium Isotopes shown in Chart of Nuclides

The cost of producing technetium will be about the same as the cost of producing rhenium so theprice of technetium should be about the same as rhenium. It would be a great loss to the world tohave technetium and some other fission products buried deep in the ground as is the plan set up by
those that have no regard for the value of technetium.
Producing Technetium99 for Medical Use by Irradiating Molybdenum With Neutrons
Technetium nuclides are shown in figure 2 which is part of the overall chart of nuclides developedby General Electric.(2) The technetium 99 made by radiating molybdenum with neutrons. The
produced technetium-99 is the nuclide shown in the left side of the 99Tc in the chart in figure 1.
Note this nuclide has a very short half life of just 6.01 hours and it has gamma radiation energy
level of 0.1405 which makes it a good indication of its location in body cells. This 99Tc nuclide wasinjected into the author to locate any cancer cells that left the prostate cancer before it was removed.
Several cancer cell locations were discovered and they were taken care of with radiation to destroy
them.
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Technetium for medical use is quite different from the structural technetium metal, but they both
can have a very useful ability and should be continually developed.
Metal wire tubes are put into arteries and veins to keep them open. However for many people themetal becomes coated with the blood contents and blocks the flow. Low level beta radiation stops
the deposition of the blood components so it may be a good application of the structural technetium
metal for medical use.
Summary
The nuclear technology period has brought us some very important learnings and there will be
millions more worth trillions of dollars to us in the future. Technetium-99m with the short half life
for medical use and the 99Tc with low radiation and long half life are going to see much more use as
we learn with time. As we learn to economically take technetium and other useful elements fromthe used nuclear fuel fission products the so-called waste elements will be a great economic
addition to our technical world.
References
1. Technetium, A Manmade Sister Element And Backup Alloying Element For Rhenium by
Edwin D. Sayre, in Rhenium and Rhenium Alloys, Symposium, Edited by B. D. Bryskin,
The Minerals, Metals and Materials Society, 1997.
2. 2. The Chart of The Nuclides updated by F. William Walker, Dudley G. Miller and Dr.
Frank Feiner, 1983 General Electric Company.

ISTR2011 participants in the Red Hall of Presidium of Russian Academy of Sciences

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5.P2.
INFLUENCE OF OXOCHLORO-THIOPYRINE RHENIUM(V) COMPLEX
ON RADIATION RESISTANCE OF CELLULOSE DIACETATE
N.S. Beknazarova, A.A. Aminjonov
Tajik National University. (Rudaki Avenue 17, Dushanbe, Republic Tajikistan). azimjon51@mail.ru

The concentration of the complex which appears to maximum effect as an additive for none
owner diacetate cellulose. Based on the analysis of dependencies tensile strength of the radiationdose -radiation has been concluded from the fact that the maxima of these curves can be used to
produce cellulose acetate material having improved physical and mechanical properties. Found thattiopirin manifests in relation to cellulose diacetate as light stabilized and antistatic properties.
Keywords: polymer, - radiation, diatsetat cellulose, thiopyrin, rhenium (V) complex.
Products made of polymer materials are widely used in agriculture, aviation, nuclear,electronic and space technology. Based on polymers made household items and medical supplies. In
the operation of polymer materials change their transparency, chemical, mechanical and electricalproperties. Thanks to modern technology has now developed methods for producing thin films andfibers, which are used as thermal and electrical insulation, and reinforcing materials. During
operation and storage of polymers and products based on them are exposed to many physical andchemical factors. Under the influence of these factors is aging of polymers, which is associated withdeterioration of their physical, mechanical and other characteristics.
To stabilize the operating characteristics of polymers are used in different ways. One
effective way of increasing the polymer stability to the effects of external factors such as light, heat,radiation, and various types of mechanical stress is the introduction into their structure modifying
agents. Among the commonly used additives for the stabilization of certain properties of polymer
and polymer composite materials occupy special place sulfur-containing compounds. For example,
2-merkaptobenzimidazol used as a stabilizer in rubber and polyolefin’s. Thiourea derivatives are
effective stabilizers of rubber. 2-mercaptobenzimidazol is an accelerator of rubber and polyolefinstabilizing process. The application of polymeric materials from year to year has greatly expanded.
In [1,2] found that in photo-2-merkaptoimidazol and 1-methyl-2-merkaptoimidazol show fairly
good stabilizing properties in respect of cellulose diacetate (DAС). It is shown that the 1,2,4triazoltiol-3 (5) significantly slows the process of photodecomposition of DAС. The assumption
was made that the reason is the screening effect of 1,2,4-triazolitol-3(5). The authors of [3] studied
the effect of 2-merkaptobenztiazol to the light fastness of DAС. Light stabilized effect this additive
has been studied both in terms of photo-aging and in photomechanical destruction. It was shownthat the maximum effect of the light stabilizing takes place in photo aging with the introduction of
the DAС 0.5% 2-merkaptobenztiazol and in photo mechanics 3%. By means of electron
spectroscopy and photoluminescence analysis proved that the 2-merkaptobenztiazol is a goodquencher of electronically excited states of the macromolecules of cellulose diacetate. In [4]experimental data on the effect of different concentrations of N,N-ethylenethiourea light fastness on
DAС is presented. It is shown that the introduction of the DAС small amounts of N,Nethylenethiourea (0.001%) light fastness when exposed to UV DAС - radiation with  = 254 nm at
25-hour exposure increased 3.4-fold.
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Experimental part
We conducted researches on influence the effect thiopyrin for light fastness and irradiation, andto electrifing diacetate cellulose. To obtain polymer films cellulose diacetate solutions in DMF
containing different amounts of thiopyrin were prepared and after filtration through the filter of
Schott (since 100), evenly placed in a glass cell, and placed on a horizontal surface weight-VLT a
specially upgraded for this purpose. After that, the cell was covered with glass and slow evaporationof the solvent took place. The resulting films were dried in a vacuum oven (vacuum 10-2) at 5000C.
Samples for mechanical testing were produced using the knife of figure that provides thefollowing geometric dimensions: length of the working part of samples l = 22mm, width d = 2mm.
The sample thickness was measured with an accuracy of 20.5 mm and ranged from 40 to 60
microns. As a source of UV light bulb used LUVs - 30, 80% of the radiation which is light with awavelength of 254 nm (J = 0,040 cal/cm2 min).
The samples were irradiated with equal doses of UV light, and then were tested in uniaxial
tension. Mechanical tests were carried out using discontinuous machines with a constant loading
rate 12 mm / min. Breaking removal and tensile strength of the samples was determined by theformula:Е p (%) hg  h0lh 100%;

p

КП
hp

(1   )2SммP = K (Hh)Where n - the multiplicity of breaking machines;
K-cruelty springs dynamometer;
S - Cross-sectional area;hg - elongation of the samples;
h0 - correction factor;
The radiation intensity of LUVs-30 was measured using a thermoelectric actinometer AT 50 and recorded the measurements of the emf potentiometer PP - 63. Source - radiation chamberserved as RHM- - 20, D-0, 19 • 106 R / h.
Results and discussion
Table 1 shows the experimental data on the effects of UV - irradiation with  = 254 nm on thetensile strength of the original DAС and DAС containing various concentrations of tiopirina.

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Table 1.Effect of UV - irradiation with = 254 nm on the tensile strength of DAС containing various
concentrations of tiopirin

0

0
11,2

2
9,1

Bursting strength, kg/мм2
Radiation time, hour
5
10
15
6,5
4,4
3,7

0,001

10,9

9,9

9,0

7,1

6,2

5,9

5,6

0,05

11,3

9,7

8,9

8,3

7,5

7,1

5,9

0,1

11,4

10,8

9,3

8,9

8,1

7,8

6,2

0,5

11,3

10,9

9,8

9,4

8,8

8,3

6,4

1,0

11,1

11,0

10,1

9,5

9,1

9,0

6,5

2,0

11,6

11,5

10,9

9,8

9,7

9,4

7,1

3,0

11,4

11,2

11,0

10,0

9,8

9,5

7,9

5,0

11,0

10,8

11,0

10,8

10,2

9,1

7,4

Additive
ratio, %

20
2,9

25
2,6

The data in Table 1 show that the introduction of the cellulose diacetate thiopyrin concentrations
0,001-5% by weight of the polymer has virtually no effect on its initial tensile strength, but at thesame time there is a significant of supplementation light stabilizing effect. Thus, the introduction of
0.001% tiopirina of the DAС within 25 hours of UV - irradiation of the initial tensile strength of thefilm from DAС decreases from 10.9 to 5.6 kg/mm2 that is 1.95 times, whereas the irradiation DAС
not containing added initial tensile strength decreased from 11.2 to 2.6 kg/mm2 that is 4.31 times.
These data suggest that the introduction of the DAZ 0.001% polymer additive light resistanceincreases 2.2 times. The data in Table 1 shows that with increasing concentrations of tiopirin
resistance to UV - radiation increases. This experimental finding can be interpreted in favor of thescreening mechanism of the influence of additives on the light fastness DAС.
Because of the sulfur-containing compounds have a definite effect on the electrified
materials based on cellulose acetate, we conducted a study on the effect of different concentrationsof tiopirina on electrified DAС. Moreover, electrostatic charges applied by the friction of medical
cotton tape. Electrified films from DAС were measured by a vibrating electrode. Registration of thecharge decay was performed using a digital voltmeter with an accuracy of 2 mV immediately after
application of electrostatic charges.
Table 2 shows the experimental data on the effect of different concentrations of tiopirina onelectrified DAС.

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Table 2. The dependence of the static charge on the surface of DAС on the time and the percentage of
tiopirine

The size of the static charge, у.е.

t,
minConcentration tiopirinа
0

0,01%

0,5%

1,0 %

2,0%

0

46,8

32,1

30,2

22,3

14,2

0,5

37,1

30,2

26,4

16,3

12,1

1,0

34,3

28,1

22,2

14,2

11,7

1,5

31,9

26,2

20,1

13,7

11,0

2,0

30,3

22,1

18,4

12,5

10,7

2,5

29,8

20,1

16,8

11,8

9,9

3,0

29,1

19,2

16,0

11,1

9,1

3,5

29,4

19,0

15,1

10,7

8,9

4,0

29,2

18,3

14,8

10,0

8,2

4,5

29,0

18,0

14,2

9,6

8,0

5,0

28,8

17,9

14,1

9,3

7,8

5,5

28,7

17,2

13,8

8,9

7,2

6,0

28,6

17,0

13,7

8,8

7,0

6,5

28,7

16,9

13,5

8,7

6,0

7,0

28,7

16,7

13,3

8,5

6,7

7,5

28,8

16,4

13,1

8,2

6,5

8,0

28,9

16,2

12,9

8,1

6,3

9,0

28,9

16,0

12,7

8,0

6,2

10,0

28,8

15,8

12,1

7,7

6,0

The data in Table 2 shows that the introduction of the 0.01% thiopyrin into the DAС conducts to a
reduction in the initial electrified from 46.8 USD to 32.1 cu that is almost 1.5 times. With
increasing concentration of antistatic additive activity against DAС increases. Introduction of theDAС additives in a concentration of 2% reduces the electrified polymer in the initial time to 3.3fold, and for 10 minutes at 4.8 times. In other words, thiopyrin has good antistatic properties inrespect of DAС.
Found that thiopyrin manifests in relation to cellulose diacetate as light stabilized andantistatic properties.
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We also conducted researches on influences studied the effect of different concentrations of
the complex [ReOL2Cl3]. 3H2O, where L - tiopirin on the electrical characteristics of the (v, s, E0,Emax) and the time semi decrease charge (τ0 and 5) from the surface of the film diatseta
cellulosions (DAС) after charging him corona. The experimental data presented in Table 3.
Table 3. The influence of complex composition [ReOL2Cl3]•3H2O, where L- tiopirin on the electricalcharacteristics of the DAС

Complexconcentration, %0τ 0,5,
min126,4

Е0, В/смЕmax, В/см v, Ом ·см s , Ом207

491

10·101339,2·1013

0,01

76,6

120,3

228,4

2,9·1013

9,8·1013

0,05

64,9

90,2

150,3

2,3·1013

9,1·1013

0,1

17,4

73,8

139,4

2,0·1013

8,9·1013

0,5

4,9

35,8

70,3

1,9·1013

8,0·1013

1,0

1,6

20,1

35,9

1,7·1013

7,9·1013

2,0

2,7

17,0

30,5

1,0·1013

1,5·1013

3,0

2,8

17,3

31,1

1,8·1013

2,6·1013

These tables indicate that the introduction of the DAС different concentrations of the complex leads
to a significant reduction in time semi decrease charge from the surface of the samples after
charging them a corona discharge. At the same time are improving other electrical characteristics(E0, Emax v, s,) of the polymer. Semi decrease time charge from the surface of films containing no
additive DAС complex appeared to be 2 hours 11 minutes. This figure is the minimum
concentration in the management of the complex (0.01%) is reduced to 1 hour and 28 minutes,
which is 1.65 times. In the concentration range of complex 0.01 - 1.0% of the value of τ0, 5 iscontinuously reduced, and a further increase in additive concentration of 2.0 to 3.0% is a small
increase in τ0, 5. The minimum value of τ0, 5 - is observed for films of DAС containing 1.0% of
the complex. The value of τ0, 5 - reduced from 126.4 to 1.6, is 79 times. Observed decrease in thevalues of the electrostatic field of the surface charge technology E0 (before charging corona). This
figure is for samples containing 0.01% of the complex is reduced to 1.72 times, and the introductionof 2.0% additives - a 12.18 time. The minimum value of Emax, v, s is observed for samples
containing 2.0% DAС complex.
Thus, the complex composition [ReOL2Cl3].3H2O, where an L –tiopirin can be used as
antistatic agents for effective materials based on diatseta cellulose.
Studies on the effect - radiation on the tensile strength of films diatseta celluloze
modify tiopirin and complex rhenium (V) with it set to high none own properties. The experimental
data presented in Tables 4 and 5.

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Table 4. Dependence of tensile strength on the concentration of DAС thiopyrine time and γ-irradiation(starting dose chamber RHM-γ -20, D = 0,19 • 106 p / h)Concentration
О
0,001
0,05
0,1
0,5
1,0
3,0

8,0
7,9
8,0
8,2
8,3
8,6
8,0

8,4
7,6
7,8
7,9
8,0
8,2
8,3

6,1
7,2
7,9
7,9
7,9
8,0
8,0

Bursting strength, kg/ mm
Exposure dose, rent/hr 1 0
5,9
4,8
4,2
6,4
5,7
5,1
6,7
6,0
5,7
7,4
6,9
5,9
7,6
7,4
6,8
7,7
7,6
7,0
7,8
7,7
7,3

3,8
4,0
4,9
5,3
5,7
6,0
6,6

1,6
2,0
2,2
2,0
2,1
2,2
2,1

Table 5 . The dependence of the tensile strength of DАС concentration of the complex [ReOL2Cl3], where Lthiopyrine and γ-irradiation time (Initial dose chamber RHM-γ -20, D = 0,19 • 106 p / h)Concentration[ReOL2CI3]
О
0,001
0,05
0,1
0,5
1,0
3,0

О
8,1
8,3
8,6
7,9
8,2
8,5
8,4

3,2
6,4
8,4
8,9
8,0
8,3
9,2
9,0

6,3
6,0
8,8
9,3
9,9
10,1
10,9
11,2

Bursting strength, kg/ mm
Exposure dose, rent/hr 1 0
9,6
19,0
38,0
5,0
4,3
4,0
9,4
10,2
9,6
10,2
11,3
11,8
12,3
13,8
12,2
13,4
14,0
14,1
13,6
14,4
14,6
13,8
14,6
15,0

95,0
3,3
9,0
10,2
10,0
12,4
13,7
14,2

190,0
1,8
6,8
7,2
7,8
7,5
6,9
7,0

It was found that the introduction of the cellulose diacetate uncoordinated thiopyrine its tensile
strength under the influence of -radiation is much slower than in the original DAС is reduced.
Thus, the strength of samples containing 0.1% DAС tiopirin exposed - radiation from X-ray doseof 95 / h compared to samples not containing this additive are 1.4 times greater mechanical strength.
With increasing concentration of radiation resistance thiopyrine DAС increases, due to the shielding
mechanism of action of this additive. On the curve of the breaking strength of the radiation dose  radiation peaks do not appear. A different picture is observed when introducing complex of oxo
rhenium (V) with tiopirin. Even with the introduction of low concentrations of oxo rhenium
complex (0,001% by weight of polymer) under the action of -radiation occur the growing
importance of tensile strength. At this concentration, addition of hardening process of cellulose
diacetate films from occurs until the effects of radiation dose -19 ∙ 104 Roentgen / hour. At thisdose of film hardening factor of 1.3. Further increase in dose lead to a slow decrease in tensile
strength values. At a dose of 190 ∙ 1010 Roentgen / hour film of unmodified DAС become brittle
and to determine their strength becomes very difficult. Samples of the films containing diatsetat
cellulose 0.001% of the complex of rhenium (V) at the dose of radiation maintain their appearance
and plasticity, and their tensile strength by comparison of the modified non-irradiated film
decreases from 8.3 to 6.8 kg/mm2 kg/mm2 that is 1 2 times. It should be noted that the tensile
strength of the polymer containing no additives of the complex under the influence of -radiation at
a specified dose is reduced from 8.1 to 1.8 kg/mm2 kg/mm2, that is 4.5 times. With increasing
concentration of the complex increases its anti-radiation effect. According to the results of
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experimental studies defined interval the concentration of the complex which appears to maximum
effect as an additive for none owner diacetate cellulose. Based on the analysis of dependencies
tensile strength of the radiation dose -radiation has been concluded from the fact that the maxima ofthese curves can be used to produce cellulose acetate material having improved physical andmechanical properties.
Reference
1. A.A Aminjanov. Complex compounds of rhenium (V) with amide ligands and tioamidnymi:
avtoref. Dis. ... Dock. Chem. Science. – Ivanovo ( 1992)42p.
2. K.U. Akhmedov, Synthesis and study of complexes of rhenium (V) with tiosemikarbozidom andits derivatives: Author. diss. ... Candidate. Chem. Science - Ivanovo (1986) - 22 p.
3. B.N. Narzullaev, A.A. Aminjanov, K.U. Akhmedov, H.D.Dodomatov, S. Narzullaev .Effect of 2merkaptobenztiazola lightfastness on cellulose diacetate, Proceedings of V All-Union Conferenceon Chemistry and physics of cellulose, Tashkent (1982)
4. E.D.Goziev N, N'-ethylenethiourea complexes of rhenium (V) and some aspects of theirapplications Abstract. diss. ... Candidate. Chem. Science Dushanbe, (2007). 22P.

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5.P3.
PLASTIC DEFORMATION OF RHENIUM AND PLATINUM-GROUPMETALS
I.G.Roberov, N.B.Gorina, G.S.Burkhanov
IMET RAS, Moscow

Plasticity, as well as strength is a complicated function of several terms i.e. the nature of theinteratomic bond, macro-and microstructure, various kinds of defects, external factors (temperature,pressure, composition), test conditions (stress state, strain rate, surface condition, scale factor ), etc.
Plasticity is not only the property but also the state of matter.
Rhenium and technetium,by their physical and mechanical properties,are close to platinum-groupmetals. They are distinguished by high degree of strain hardening, which makes the process ofobtaining rhenium semi-products very labor-intensive. Rhenium isthe only of alloying elements,
which increases both ductility and strength of tungsten and molybdenum (rhenium effect),
neutralizing the harmful carbon and oxygen effects on physical and mechanical properties.
Of platinum-group metals, only palladium and platinum have high ductility. Rhodium and iridiumof technical purity, having the same crystalline structure, are fragile. In the state of technical purity,
ruthenium and osmium are practicallyno deformable.
Deep cleaning of rhenium and platinum-group metals sharply increases their ductility. Investigationof structure and properties of rhenium and platinum-groupmetals in the pure poly-and single-crystal
stateshas enabled to determine the contribution of impurities to changing their plasticity, the causeof brittleness and deformation mechanisms.
Developed on the base of studies, the regimes of plastic deformation have enabled to obtain thinfoils of iridium, rhodium and rhenium. For the first time, by plastic deformation, it is obtained
ruthenium foil by thickness of less than 1 mm.

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6
Tc and Re nanotechnology and applications in the field of
nanomaterials

The chairman of the 6-th section corr.-member RAS B.G. Ershov
in the President Hall of RAS

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6.1.
SYNCHROTRON DIAGNOSTICS OF FUNCTIONAL NANOMATERIALS
Ya.V. Zubavichus, A.A. Veligzhanin, A.A. Chernyshov, E.V. Guseva
National Research Centre “Kurchatov Institute” (Kurchatov sq.1, Moscow 123182, Russian Federation)

Synchrotron radiation (SR) offers unique capabilities in structural characterization ofcomplex functional materials. Nowadays, there are about 70 operating SR centers all over theworld. Russia hosts two of them located at the Budker Institute of Nuclear Physics (Novosibirsk)
and Kurchatov Institute (Moscow).
This lecture surveys current status and future plans of experimental stations installed at theKurchatov Synchrotron Radiation Source.
The emphasis is placed on the design and recent results obtained with the “Structural
Materials Science” end-station. This station is dedicated to structural investigations of noncrystalline and nanostructured materials by a set of mutually complementary methods, viz. smallangle X-ray scattering (SAXS), X-ray powder diffraction (XRD) and X-ray absorption spectroscopy(EXAFS/XANES).
These techniques yield structural information at different distance scales over the range of
0.1-100 nm (interatomic distances, unit cell parameters, size of crystallites/particles/pores, etc.) thus
enabling more comprehensive characterization of a material.

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The station is equipped with a special sample environment chamber to study samples under
non-ambient conditions (high/low temperature and a specific gas atmosphere, including vacuum,inert gases, oxidative/reductive gases, etc.). This is especially important for functional materials
since a structural study can be performed under conditions similar to those required for their target
exploitation.

Over the last few years, diverse classes of functional materials have been elucidated,
including supported catalysts for petrochemical processes, metal alloys, polymers, functional metaloxides and complexes.
The logic of application of different synchrotron X-ray techniques to solve specific structuralproblems is discussed. Possibilities and advantages of combined utilization of several techniques
are illustrated with a number of examples.

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6.2.
MANUFACTURE OF NANO- AND ULTRADISPERSE POWDERS OFRHENIUM AND REFRACTORY METALS FROM TECHNOGENIC RAW
MATERIALS.
A.I. Kostylev, U.G. Pokrovskiy, I.D. Troshkina1, N.G. Firsin, A.M. Chekmarev1
FSUE «RPA «V.G. Khlopin Radium Institute», (2 Myrinskyi prosp., 28, Saint-Petersburg, Russian Federation)
1

D. Mendeleev University of Chemical Technology of Russia, (Moscow, Russian Federation)

Keywords: powders of rhenium, electrochemical process, rhenium heptoxide, hydrogen reduction,
controlled particle size.
Abstract:
This report contain the results of research concerns the production of powders of rhenium and somerefractory metals from industrial wastes. The aim of the work was to develop the best technologicalsolutions and investigate of key stages in pilot industrial scale production: dissolution of raw
materials, the separation of multicomponent mixtures of metal compounds and obtaining of highpurity rhenium, tungsten and molybdenum powders of a controlled phase and particle size.
Production is focused on getting the final product: nano-and ultrafine powders or microgranules in aform suitable for use in powder metallurgy of superalloys and special refractory alloys.
As a raw material in the process mostly imported waste heat-resistant nickel alloys of
GSMX-4 and MK-4 were used. Full technological cycle of processing involves the following
stages: electrochemical crushing, sulfuric acid leachimg, plasmochemical oxidation, adsorbtion andion exchange purification of ammonium perrenate, hydrogen reduction, CVD – process of receptionof rhenium.
Introduction
Consumption of rhenium in the next 10 years is projected at least 70 - 80 tons per year [1 - 3]. For
example, in civil and military aviation technology application of the rhenium superalloys according
to the plans of leading companies (Cannon Muskegon, Rolls Royce, Pratt & Whitney, General
Electric) and estimations of the collaboration of manufacturers of aviation turbine «Engine OEMs
Collaborate» will increase at least until 2027 and in the next few years (until 2018) will be at least
60 - 70 tonnes of rhenium per year. That is due to the fact that 40 - 50% of the parts in modern
aircraft engines are made from rhenium superalloys. Next important field of the rhenium
consumption is production of reforming catalysts and catalysts of natural gas processing in the socalled GLT - process. According to opinion of catalyst leading manufacturers the need of rhenium
in this sector over the next 10 years will be about 16 tons per year. Production of primary rhenium
in connection with the specifics of the geochemical distribution in this period can be 50 - 60 tons
only.
A noticeable increase in the production of rhenium is impossible due to lack of new
discovered fields. This deficiency (between the primary production of rhenium and the needs ofindustry) should be covered by the secondary rhenium obtained by recycling of industrial wastes.
Demanded volume of rhenium production from industrial wastes for the next decade is estimated by
the world leading producers of rare metals in amount not less than 14 tons per year.
The primary market for recycled rhenium is mainly represented by large pieces and turbine
parts made of nickel-based superalloys. Superalloys - complex alloys with heterophase structure
whose main elements – disperse (1 - 0.5 micron) particles of γ'-phase on the basis of the orderedintermetallic compound Ni3Al and nickel complex-γ-solid solution [4]. Practical experience inprocessing of this raw material was obtained in the operation of pilot production, which was
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organized in 2004 in the Federal State Unitary Enterprise " Morozov Plant" in the Leningrad region.
Recycling of heat- resistant rhenium alloys (grinding powders) to yield as the main products ofrhenium in the form of ammonium perrhenate, powder and sintered rods from it was carried out at
this production. As a co-product ultrafine nickel powder and nickel oxalate were manufactured. Alarge part of produced rhenium in the form of sintered rods (pellets) comes to produce alloys to
Stupino Metallurgical Company. Scheme of processing was based on nitric acid leaching followed
by separation of rhenium and nickel with the use of crystallization of sparingly soluble salts andion-exchange treatment. Experience in operating production, mainly using hydrometallurgical
techniques, allows to identify the following disadvantages: a large amount of acidic liquid waste,
not efficient use of resources: cobalt, tungsten, molybdenum, they are not extracted and remain in
solid waste dumps production, poor efficiency, unefficiency of processing of the scrap and scrap
waste of heat-resistant nickel alloys. In this regard, parallel works on improving technology in thefollowing areas are carried out: the development of economical method for waste crushing,replacement of nitric acid oxidation to plasma processing of materials to make the process simpler,increase productivity and reduce the amount of liquid waste, integrated processing of raw materials
with extraction of valuable components from alloys (nickel, cobalt, tungsten, molybdenum) withmodern efficient methods, development and implementation of technology for rhenium productionin the form of ultra-and nanopowder.
Experimental
The unique microstructure of superalloys defines completely unique stability of the material tomechanical stress and chemical agents. The usual dissolution methods of this materials (acidic,
alkaline, oxidizing melting, etc.) are not effective [5 – 7]. At the same time, the electrochemical
processing of the alloy (in sulfuric acid solution at a potential of the anode ≈ 1 and temperature t =20 - 50 ° C, platinized titanium at potential ≤ 0,6 V is used as the cathode) provides quite rapid
breakdown of the material. Under these conditions at the anode, electrochemical dissolution
reaction of nickel situated in the grain boundaries of the alloy occurs. Except for nickel, as part ofthe matrix (γ-phase) there are some other components of the alloy: cobalt, iron, chromium andmolybdenum. So the electrochemical process of the intergranular fracture of the alloy isaccompanied by transition to a solution of these metal ions, cobalt, iron, chromium andmolybdenum. Transition to a solution of rhenium as a perrhenate- ion can be observed. In practice,
the really attainable level of electricity consumption is about 1.3 kW • h per kg of damaged alloy.

MK-4 Alloy

Product of electrochemical destruction
Fig.1. Electrochemical destruction.

The next stage of the process, sulfuric acid leaching, is carried out in sulfuric acid solution at
the temperature of 85 - 95 ° C with stirring. The main chemical reactions that occur at this stage are
the dissolution reaction of nickel, aluminum, iron, cobalt and chromium. The residue after
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dissolution and washing is thin, black powder, containing mainly tungsten, tantalum, niobium,rhenium. Particles of this material have a size of about 5 - 10 microns.
The precipitate is washed to remove the bulk of sulfate and transferred to the oxidation step forrhenium extraction. From the solution after filtration, nickel, cobalt and rhenium presented insolution as an impurity (~ 5% of the total) are recovered. Nickel and cobalt are extracted from thesolution by reduction at a controlled pH, and impurity of rhenium is extracted from the motherliquor by adsorption on anionite.

10 мкм

1 мм__Electrochemical grinding alloy

Resique after leachingFig.2. Sulfuric acid leaching

Plasma oxidation is carried out in the installation of air-flame spraying with powder feed
processed in the zone of the plasma torch. As an oxidant, air is used. Temperature in the plasma
torch is 3000 - 5000 ° C, in the oxidation zone - about 1000 º C. That provides the oxidation of thepowder particles and the diffusion of volatile oxides in the gas phase. The resulting gas mixture isreleased from the solid cinder in a cyclone and enters into the adsorption column irrigated withaqueous alkali. The cooling of gas stream with an aqueous solution and adsorption of rheniumoxides are carried out in the column. At an arc current of 150 - 200 A and air flow 2 - 3 cubic
meters per hour, efficiency is reached up to 5 kg / hour. The degree of rhenium extraction from thematerial is up to 90%. Additionally molybdenum in the form of ammonia paramolybdate isremoved.
Ion exchange purification of ammonium perrhenate produces material with a quality tosatisfy to the requirements for "ammonium perrhenate for superalloys." Products have beencertified in accordance with the requirements of MMTA (Minor Metals Trade Association). The
main amount of rhenium powder so far is obtained by hydrogen reduction. Reduction is carried out
in one stage in tube furnaces with a stepped increase in temperature from 250 - 350 ° C to 800-850 °C. Physical characteristics of the powder are the next: dispersion - 1 μm, bulk density - 2.5 g/cm3,
color - gray. The resulting powder metal is subjected to further special treatment for compact
rhenium obtaining in the form of rods, which are marketable product. To do this, rhenium powder iscompressed and then sintered at 1100 - 1200oC in hydrogen atmosphere. Rhenium pellets obtainedby this method have purity level of 99.98 - 99.99% and density of 60 - 70% of the theoretical.
To get compact metal from a standard powder produced by hydrogen reduction ofammonium perrhenate procedures of very high sintering (more than 2000 º C) and subsequentmachining operations with intermediate annealing are necessary. That is a disadvantage ofobtaining powder method. That is why for organized production, ways to increase the purity of themetal, to reduce the sintering temperature and reduce losses of the metal were suggested.

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Fig.3. Manufacture of pellets of standart from scrap

This method worked on a laboratory scale is based on the obtaining of powdered rhenium byhydrogen reduction of rhenium heptoxide Re2O7 in vapor phase. In this case, the quality of themetal can be improved by additional distillation of initial oxide rhenium. Depending on process
conditions (ratio of the reactants and the carrier gas, pressure and temperature in the reaction
chamber) the rhenium powder with the dispersion at the level of 0.1 - 0.3 microns and a specificsurface area of 1 - 2.3 m2 / g can be obtained. The method allows to obtain fine unpyrophoric
powders with controlled particle size in the range 100 - 500 nm, purity above 99, 995% and theoxygen content of less than 0.2%. The use of these powders at getting rhenium and its alloys bypowder metallurgy methods can reduce the sintering temperature, increase the density of products
and improve their physical and mechanical properties.

Fig.4. Nanorhenium powder, ~0,1 μm

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90
80
70
60
Density, % 50
theor.
40

Standart, 3-10 мкм
Nano, 0,1-0,3 мкм

30
20
10
0
Pressed,
4 t/см2

Sintered1150

Fig.5. Rhenium powder is compressed under the pressure of 4 tons/cm2 and then sintered at
1150oC in hydrogen atmosphere.
Conclusion
Rods, pressed from this powder are the feedstock for obtaining some products of rhenium
like wires, foils, rods, etc. They can be rolled, stretched, hammered and put the other mechanicallyprocessing. Moreover, with increasing of dispersity, chemical purity and structural perfection of thepowders the physical and mechanical properties of final products, such as resistance to plastic
deformation and fracture resistance, increase sharply. Creation of material from perfect crystals of
nanometer size would allow to achieve almost theoretical strength and ductility. Superalloys, which
are currently widely used materials and the main area of rhenium use, are entering into the second
era of development. One of the key trends of their development is the use of powder metallurgy
methods based on nanopowders.
Reference
1. Lipmann W., Rhenium 2009 and beyond. The MMTA Int.Minor Metals Conference. Istambul.
Turkey. 2009;
2. The Minor Metals Age. Metals for the Aerospace Industry/Conference, Seattle. October 2009;
3. Magyar M.J., Rhenium. U.S. Geological Survey Minerals Yearbook – 2004;
4. Murakami H., The location of atoms in Re- and V- containing multicomponent nickel-basesingle-crystal superalloys. App. Surface Science, v. 76/77, 1994, 177 – 183;
5. Paul J. Fink et al., Rhenium reduction—alloy design using an economically strategic element.
JOM Journal of the Minerals, Metals and Materials Society. 2010, Volume 62, Number 1, 55-57;
6. US 2009/0255372 A1 (Publication number). Jun 29, 2007. Recycling of superalloys with the aidof an alkali metal salt bath;
7. A.V. Tarasov, V.M. Paretsky, A.D. Besser and E.I. Gedgagov. Processing of grinding waste ofrhenium-containig alloys to manufacture commercial-grade metals. Symposium General Recycling
and Solid Waste Processing: Precious and Rare Metals. Moscow. 2008.

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6.3.
NON-STOICHIOMETRIC SYNTHESIS OF RHENIUM
HEPTASULFIDE HYDROSOL
N.R. Antipkin, G.A. Biljalova, M.A. Bogorodskaya, A.O. Bogorodsky, A.B. Sazonov,
A.S. Chagovets

D. Mendeleyev University of Chemical Technology of Russia(Miusskaya sq. 9, Moscow, 125047, Russian Federation)

Keywords: nanoparticles of rhenium heptasulfide, rhenium heptasulfide hydrosol, reaction of
perrhenate and hyposulfite, colloidal stability of rhenium heptasulfide.
Abstract
The Re2S7 nanoparticles were synthesized in the exchange reaction of perrhenate andhyposulfite. Effective hydrodynamic diameter of the nanoparticles is 55 ±15 nm. The influences ofsynthesis time, acidity, ratio of reactants, and quantity of the stabilizer on the disperse phase yield
were investigated. The kinetic characteristics of this reaction and side reaction of hyposulfite
decomposition were obtained. It was found that formation of particles at a temperature of 100 оС
finishes in 2 min. The activation energy is 76 kJ/mol and 16 kJ/mol of main and side reaction
respectively. The main reaction order was determined to be 1 and 1.35 with respect to perrhenate
and hyposulfite respectively. As a result of the work, visually transparent product, stable within awide range of рН (1-9), not coagulating in saturated solutions of salts (including polyvalent cations)even at long heating up to 100 оС has been synthesized. Hydrosols can be stored in an inert
atmosphere for indefinitely long time (years).
Introduction

Rhenium heptasulfide is an effective and selective catalyst of hydrogenation and reduction.
Its stability to catalytic poisons (for example, sulfur or arsenic compounds) is unique. Its catalytic
activity is greater than one of palladium or tungsten sulfides and allows getting almost quantitative
yield at optimal conditions [1-4]. The major characteristic of a catalyst in heterogeneous catalysis is
its specific surface. Therefore, synthesis of the catalyst nanoparticles is interesting from practicalpoint of view.
Hydrosols labeled by radionuclides have found the application in nuclear medicine fordiagnostic and therapeutic purposes. The key to success here is not a chemical form of theradiopharmaceutical but the size of its nanoparticles. It’s known that optimal contrast substance for
lymphoscintigraphy must have radius of its particles in the range of 10-50 nm [5]. Such particles
can be removed from tissues with acceptable rate and can not penetrate into the blood. Recently the
nanocolloids of technecium – 99m have been widely adopted in the technique of intraoperational
visualization. This technique allows to reduce a volume of dissection and to perform less traumatic
operations in the cases of oncological diseases. Among many studied substances (proteins,
antimony sulfides, etc.) sulfide of rhenium appeared to be the preferable one. Its X-ray-amorphous
irregular shape particles appeared to be the best for radionuclide labeling for diagnostic application.
However, the desire of radiopharmaceutists to carry out the synthesis of hydrosol in a solution withisotonic concentrations of substances used to restrict the possibilities of optimization.
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The purposes of the present work were the optimization of parameters for synthesis ofrhenium heptasulfide nanoparticles, the synthesis of the hydrosol possessing aggregative stability,
and the estimation of particle sizes in the dispersoid.
Experimental
Nanoparticles have been synthesized in the exchange reaction of perrhenate and hyposulfite
in acidic medium at elevated temperature and at the presence of a stabilizer [6]:2NaReO4 + 7Na2S2O3 + 2HCl  Re2S7col + 7Na2SO4 + 2NaCl + H2OThis reaction is accompanied by a side reaction of hyposulfite decomposition:
Na2S2O3 + 2HCl  2NaCl + SO2 + Scol + H2O,
and also by formation of intermediate substances, for example, monotioperrhenate NaReO3S:
NaReO4 + Na2S2O3  NaReO3S + Na2SO4
During the synthesis rhenium was distributed over different phases as it follows. Primary
precipitate of rhenium heptasulfide (RePP) has been codeposited with particles of elemental sulfur.
It can be separated from supernatant part by centrifugation. Dispersoid (ReDS) is represented by thenanoparticles
ofrhenium
Mixing of reactants
heptasulfide(probably
with
Re loss evaluationin ice bathincorporated elemental sulfur). The
14 000 rpm
Picking up of supernatantdispersoid can be separated from
3-times acetone
solution aliquot forcontinuous medium by coagulation
washing of DS
DS coagulation
Transferring to
after
additionofacetone.
the reactor,
Continuous
medium(ReCM)
Sample preparation
DS mineralization
synthesis 2 mincontains residual perrhenate andfor spectrophotometry(Н2О2 + NH3)
intermediate products of the basic
End of synthesis
PP mineralization
14 000 rpm 3-times
reaction. Separation of the phases
and cooling(Н2О2 + NH3)
water washing of PP
has been done according to thefollowing chart (Fig. 1).
Sample preparation
Transferring into
Hydrosols are not true
for spectrophotometry
the centrifuge tubes
solutions, and for spectral analysis
Fig. 1. Experiment layoutof dispersoid it must be dissolved inammonia solution of hydrogen peroxide or in aqua regia. Thus rhenium heptasulfide may be
converted into a chemical form of perrhenate or rhenium acid. Coloured compounds are formed
after addition of hyposulfite and tin (II) chloride.
Particle size determination was taken at Zeta Potential/ Particle Sizer Nicompтм 380 ZLS(photon-correlation spectroscopy method – PCS), VEGA 3 SB (Scanning Electron Microscope –SEM) and ТECNAI-12-3R (transmission electron microscope – TEM). Visual spectra were taken
at SP-2000. Separation of the phases has been done with Centrifuge Eppendorf 5415 C.
Results and Discussion.
Properties of hydrophobic sol depend on many variables: concentrations of reactants, orderof their addition, heating, cooling and stirring mode, character of the stabilizer and the moment of
its addition.
After rhenium dissolving in peroxide solution, evaporating
it, and adding hyposulfite and tin (II) chloride known orange
complexes with a maximum of absorption at 410 nm are formed(Fig. 2).
It’s not reasonable to evaporate aqua regia since rheniumacid is volatile. Absolutely different compounds of violet color
were formed at the presence of aqua regia residues. Possibly, anitrosyl-sulphide complex of rhenium with a maximum ofFig. 2. Reduced rhenium
absorption at 530 nm was formed in that system. Thus, a newcompounds spectra
unknown complex of rhenium with molar extinction equal to
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0.82·104 M –1cm–1 has been
%
, %
synthesized. It can be used in
ReDS
spectrophotometric analysis 80
of rhenium as well. However,
40
ReDS
60
RePP
extinction of a sulphidic
Re S
compoundformedafter 40ReCM
30treatmentofrhenium
20
heptasulfide by peroxide isC(HCl), M
twice above, or 1.60·104 M –
20
1
–1
0
1
2
3 C(HCl),
4 M
0,3
0,4
0,5
0,6 C(HCl), M
cm .
Therefore,aFig. 3. Influence of acidity on the heptasulfide yieldcombination of peroxidic
dissolving and hyposulfite
treatment should be recommended for analysis.
The first series of experiments has given a chance to estimate influence of acidity on
heptasulfide yield as a whole, and its nanoparticles in particular. A total yield of rhenium
heptasulfide rises up to 80% when the medium acidity increases (Fig. 3). However, on the curve“dispersoid yield versus acid concentration” the plateau with maximal yield (about 40%) within
0.45-0.65 M concentration range is observed. This can be explained because the acid not only
catalyzes formation of rhenium sulfide, but also provokes coagulation of the dispersoid. Therefore,
for all further experiments a minimal possible value of hydrochloric acid concentration (0.45 M) has
been chosen as the optimal one.
Time is of great importance for successful synthesis.
It is shown that formation of particles at 100 oC comes tothe end during 2 minutes (Fig. 4); an increase of thesynthesis time doesn't result in increase of the dispersoid
yield, but increases a risk of its coagulation.
Since the synthesis of nanoparticles appeared to be
unexpectedly quick, it was interesting to determine theactivation energies for the basic and side reactions. For thispurpose the synthesis temperature has been varied from 40
to 100 oC. The activation energy of the basic reaction isequal to 73 kJ/mol, and the temperature factor is about 2.5.
Fig. 4. Finding optimal synthesis time
This allows to classify it a reaction going with average rate
(at normal conditions its rate is extremely low). The
activation energy of hyposulfite decomposition is equal to 16 kJ/mol, and the temperature factor is
1.2. It is a fast reaction going quickly at room temperature. When temperature rises up from 20 to
100 oC the rate of Re2S7 formation increases in 800 times, and the rate of hyposulfite decomposition
increases only in 4 times. Therefore, to increase the yield of thebasic substance and to reduce relative contribution of thehyposulfite decomposition it is necessary to synthesize
nanoparticles at the highest possible temperature.
This can be proven by dependence of heptasulfide andelemental sulfer yield on temperature (Fig. 5).
Determination of the basic reaction order with respect toperrhenate was performed at the conditions of a pseudo-zeroorder with respect to hyposulfite concentration (meaning its
excess). Initial reaction rate is directly proportional to theperrhenate concentration; it is a first order reaction.
The dependence of the Re2S7 formation rate on thehyposulfite concentration is more difficult and that is not a Fig. 5. Temperature dependencesof the Re2S7 and S yields
surprise. For determination of a formal order of the basic reaction
2 7

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with respect to hyposulfite the dependence “rate versus concentration” have been drawn inlogarithmic coordinates. The formal reaction order is equal to 1.35.
There is a consecutive substitution of oxygen atoms by sulfur atoms in the molecule ofrhenium acid formed after perrhenate-ion protonation. So, one of the intermediate products isbright-yellow monotioperrhenate-ion which formation we observed. Stages of the substitution canbe described by the following reactions:
HReO4 + H2S2O3 = H[ReO3S] + H2SO4
H[ReO3S] + H2S2O3 = H[ReO2S2] + H2SO4
H[ReO2S2 ] + H2S2O3 = H[ReOS3] + H2SO4
H[ReOS3 ] + H2S2O3 = H[ReS4] + H2SO4
The last one is formation of a sulphidic bridge between rhenium atoms.
H[ReS4 ] + H[ReOS3] = Re2S7 + H2O
One can assume that all these reactions go with different rates, and the last one is ratedetermining. The formal reaction order is equal to 1.35. Thus, in the synthesis it is reasonable toincrease the hyposulfite concentration above a stoichiometric value.
To stabilize hydrophobic soles the amphiphilic polyelectrolytes (for example, gelatin) areused. Thus the surface of nanoparticles becomes hydrophilic and their aggregative stability
increases. However, gelatin reduces catalytic activity. Moreover, being used in medicine it may
become an allergen as well as any other protein. Therefore it was necessary to determine its
minimal possible quantity needed for the synthesis. Shortening of the synthesis time from 7 to 2
minutes allowed expecting possibility of reduction of gelatin concentration. It has been shown thatafter the increase of gelatin concentration more than 1% the yield of the dispersoid doesn't change.
Further synthesis has been performed at the stabilizer concentration equal to 1.2 mass percents (Fig.
6).
Formally the stoichiometric hyposulfite–perrhenate ratio is equal to 3.5. However, becauseof the side reaction of hyposulfite decomposition, this value can appear insufficient. A total yield of
Re2S7 rises up with an increase of this ratio above the stoichiometric value. However, when the ratio
is equal to 5 or 6 the "saturation" of the dispersoid yield is observed (Fig. 7). Further increase of thehyposulfite concentration does not result in an increase of the dispersoid yield.
Though a total yield of heptasulfide increases, the most part of, %rhenium codeposits with sulfur. It is observed that at a lack ofReDS60
hyposulfite (when the ratio is less than 3.5) visually transparent
RePP
Re2S7sols can be produced. Elemental sulfur formed after hyposulfite
40
ReCM
decomposition is not allocated in a separate phase but
incorporated into the structure of Re2S7 nanoparticles.
20
However, the yield at these conditions is the smallest (less than20%). Distribution of the particles over their sizes in this case0
Cgel, %
1
2
is presented by a curve with a maximum at about 50 nm.
Polydispersity
isFig. 6. Finding optimal
, %small;
75
mass
concentration of gelatin
ReDS
percents
of
the
RePP
80
particles have hydrodynamic diameters from 35 to 75
Re2S7
ReCM
nanometers. When the ratio increases, the turbid product60
with bimodal distribution of particles over their sizes isformed. It may be consequence of different nature of the 40
particles or different mechanisms of their formation.
Indeed, the sulfur deposit easily separates during 20
centrifugation and the sol becomes transparent. The
0maximal yield of rhenium in a disperse phase reaches
Na
5
10
15
2S2OСоотношение
3/NaReO4
about 40%. Since the product can be cleared of sulfur
easily by centrifugation, without a loss of the dispersoid, Fig. 7. Re2S7 yield dependence vs thehyposulfite–perrhenate ratio
the ratio equal to 4.5 has been chosen as the optimum.
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For the purified deionized sol an effective hydrodynamic volume-average diameter is equalto 55 nm and a number-average diameter is 35 nm (Fig. 8). Small discrepancy between the twovalues means that the distribution of particles over their sizes is narrow. Diameter of a dense core
determined by a method of transmission electron microscopy turns out to be 10-20 nm (Fig. 9).

Fig. 8. Particle size distribution (effective hydrodynamic diameter)cbaFig. 9. Re2S7 nanoparticles electronic photography: a – SEM, b, с – TEM

Comparison of hydrosols obtained by different methods is given in the Table 1.
Table 1. Characteristics of hydrosols obtained by different methods
Со(Re), Na 2S2O3g/l
NaReO 4

С(HCl),M

Сgel, %

Synthesis time,min

Hydrodynamic diameter,
nm

[7]

0.36

6.07.0

0.070.11

0.81

3.5

 1000[8]

0.59

3.07.1

0.125

0.17

610

< 100 (60%)
100200 (14%)

[9]

0.48

4.8 7.7

0.20

4.0

35

<50 (20%)

Present
work

0.60

4.5

0.400,45

2.2

25020 (100%)

Reference

Conclusions.
As a result of the work, visually transparent non-opalescent hydrosol of Re2S7, stable within arange of рН from 1 to 9, not coagulating in saturated solutions of salts (including polyvalentcations) even at long heating up to 100 оС has been synthesized. An effective hydrodynamic
volume-average diameter is equal to 55 nm and a number-average diameter is 35 nm (PCS). An
effective hydrodynamic diameter is at least 2 times more than diameter of the dense core. Re 2S7nanoparticles are irregularly shaped, X-ray amorphous. Deionized hydrosols can be stored in an
inert atmosphere for indefinitely long time (years).
This work may be also helpful in developing synthesis of other hydrosols of metal sulfides(anthymony, molibdenum and so on).
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References
1. M.A. Ryashenceva, H.M. Minachev; Renii i ego soedineniya v geterogennom katalize, Nauka:
Moscow, 1983, p. 248 (in Russian).
2. T.A. Pal'chevskaya, L.V. Boguckaya, V.M. Belousov, Ukr. Him. J. №3: 240-243 (1989) (inRussian).
3. V.I. Savel'eva, I.D. Sokolova, B.V. Gromov, M.A. Ryashenceva, Trudy MHTI im. D.I.
Mendeleeva. 69: 151-154 (1972) (in Russian).
4. V.I. Savel'eva, B.V. Gromov, M.A. Ryashenceva, Trudy MHTI im. D.I. Mendeleeva. 71: 148151 (1972) (in Russian).
5. N.S. Lyubarskii, A.I. Shevela, M.R. Kolpakov, R.S. Hanaev, V.V. Ilmaev, Flebolimfografiya.
№ 17: 8-14 (2003) (in Russian).
6. G. Remi; Kurs neorganicheskoi himii. 2. Mir: Moscow, 1966. 836 p. (in Russian).
7. Koren. Registracionnoe udostoverenie № 81/1116/3. Vremennaya farmakopeinaya stat'ya 421150-81 ot 17 avgusta 1981 g. (in Russian).
8. ISSN: 0315-162X (ISSN print). Patent. Zabel, Pamela Louise; Dunn, Kent. Colloid for
scintigraphy. Patent Number: US 6706251 Patent Date Granted: March 16, 2004 Patent
Country: USA Patent Assignee: London Health Sciences Centre, London, AR, USA PatentClass: 424-129 Official Gazette of the United States Patent and Trademark Office Patents 1280
(3) Mar. 16, 2004.
9. Tsopelas, Chris, Journal of Nuclear Medicine. 42: 460-466 (2001).

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6.4.
CONTROLLED SYNTHESIS OF ULTRA DISPERSED (NANO SIZED)RHENIUM OXIDES (IV) AND (VI): SYNTHESIS OF PRECURSORS AND
PROPERTIES OF THE MATERIALS

K.A.Smirnova, D.V.Drobot, A.I.Lvovskiy, O.V.Petrakova

Lomonosov Moscow State University of Fine Chemical Technologies(Prosp.Vernadskogo 86, Moscow, Russian Federation)

Keywords: rhenium, alkoxides, thermal decomposition, nano sized oxides
Abstract:
Electrochemical syntheses of complex of rhenium with n-butanol ReO3(OBun)∙mBunOH (I)and heteroligand complex of rhenium with ethanol and isopropanol Re4Ox(OEt)y(OPri)z (II) havebeen elaborated. It was shown that thermal decomposition of (I) and (II) allowed to produce ofnano sized rhenium (IV) and (VI) oxides.
Introduction

Recently the interest to chemistry of rhenium compounds and a problem of synthesis of newmaterials on its basis has considerably increased. The interest is caused by unique and important
properties of rhenium compounds [1]. In particular, alloys of rhenium with other refractory metals
are characterized by a combination of useful mechanical properties (durability, hardness, plasticity)[2]. A significant amount of rhenium compounds are used in manufacturing of catalysts possessing
high activity and selectivity in various organic and inorganic reactions [3]. It is known that theapplication of nano sized particles in catalysis allows to reduce the expense of active components.
Therefore ultra and nano sized rhenium oxides arouse the practical interest because of their special
physical and chemical properties [4].
The aim of work is development of method of controlled synthesis of functional ultra
dispersed (nano sized) materials by using of homo- and heteroligand rhenium alkoxocomplexes asprecursors. Electrochemical synthesis was improved to obtain ReO3(OBun)∙mBunOH (I) andRe4Ox(OEt)y(OPri)z (II).
Experimental
The electrochemical method has been used for synthesis of complexes (I) and (II). The
scheme of an electrochemical cell is presented on fig. 1.
Conditions of synthesis of complexes (I) and (II) are presented in Table 1.

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Description:
1 - drying agent (P2O5)
2 - reflux condenser
3 - water for cooling
4 – comparison electrode5 - cathode (Pt)
6 - anode (Re)7 - membrane from porous glass
8 – thermometer

Thermal properties of a complex of rhenium
Fig.1. An electrochemical cell for
ReO3(OBun)∙mBunOH in the range of temperatures fromsynthesis of alkoxides
22 to 420 °С were investigated. Heating was carried out on
air with a speed 5 °С per minute. Differential temperature curve is presented on fig. 2. For studyingof thermal decomposition of a complex (I), for determination of structure and investigation ofproperties of products of decomposition, isothermal annealing has been carried out at fivetemperatures (1800С, 1900С, 2000С, 3000С,
Table 1. Conditions of electrochemical synthesis of3400С). The analysis of thermogram allows torhenium alkoxides
state that at T=185 0C the first step of weightloss of the sample comes to the end, therefore
Conditions
III
the sizes of particles in this area of
Anode
Re
Re
temperatures (1800С, 1900С, 2000С) have been
CathodePt
Pt
defined, other two points were chosen so that
Electrolyte(n-BuOH) n(i-PrOH) : n(EtOH) = to come nearer to conditions in which weight
1:1 mole/mole,loss has ended. The temperature was chosen
membrane
not above 340 0С as sublimation of Re2O7 was
possible.
U, В150-200
200-240
Synthesis products of complexes (I) and
I, mA
30-80
10-50
(II) have been characterized by chemical
Duration, h
48,5
112,0
analysis, X-ray and IR methods. Found for
LiCl, mole/l0,10,1complex (I): C- 40,0; H 5,5; Re 13,5 wt.%.
Mass of2,6
1,3
The empirical formula of a complex (I) dissolved Re, g
ReO3(OBun)∙mBunOH. IR, cm-1: 3338 (ν ОН), 1072-1114 (ν С-О), 2873-2959 (ν С-Н), 953-1044 (ν Re=O), 628 - 904 (ν Re – O, the bridge),
516 (ν Re – O (R)).
Found for complex (II): C 9,12; H 1,74 wt.%.
The general formula of a complex (II) (Re4Ox(OEt)x(OPri)y). IR, cm-1: 1078 (ν С-О), 920 (νRe – O – Re), 893 (ν C – C), 540 (ν Re – O (R)), 464(ν Re – OR (bridge)).
For revealing of dependence of structure of
products of decomposition from temperature,
isothermal annealing has been carried out in air (Table
2).
The following stage of work was measurement of
the sizes of particles of the samples obtained at
isothermal annealing of a complex (I). Measurement of
the particles sizes was performed on the Delsa™Nano
Submicron Particle Size and Zeta Potential Analyzer
PN A54412AA. Also dependences of number ofFig.2. DTG-TGA analysis of complex (I) in
particles (ν, %) from diameter (d, nm) at various
air, Тmax = 420 °C
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temperatures (Fig. 3 (a)) and number ofnano sized particles (T, 0C) (Fig. 3 (b))
were investigated.
In all dependences there is a
maximum which corresponds to thegreatest number of ultra dispersed (nanosized) particles formed at the fixed
temperature. Such distribution ofparticles in the sizes is caused by thereason that the complex decomposes notcompletely; hence, the quantity of nanosized particles is small. The complex
decomposes at a rise in temperature andduration of annealing, so the quantity ofnano sized particles is increased.

aTable 2. Conditions of isothermal annealing ofcomplexes (I) and (II)SampleT,0С

Dur., h(I) - 1180

7

Decomposition
product
ReO3cub(I) - 2190

4-(I) - 3200

2

ReO2orth+ReO3cub(I) - 4300

5-(I) - 5340

6(II) -1

245

8

ReO2orth + ReO3cub
ReO3cub(II) -2

255

34

ReO3cub(II) -3

265

4

ReO2orth+ReO3cubb

Fig.3. Dependence of number of particles (ν, %) from diameter (d, nm) of the product ofthermal decomposing of the complex (I) in air (a) and number of nano sized particles(ν, %) from temperature (T, 0C) (b)At the further rise of
Table №3. Distribution of the sizes and number of particles oftemperature the agglomeration products of thermal decomposition of the complex (II) depending
happens, the number of nano on temperature of annealing for various ranges of measurement ofsized particles is decreased. As diameter of particles

shown on Fig.3 (b), attemperature
2000С
the
Range of measurement of diameter
maximum quantity of nano sized
Т, 0С
υ, %
d, nм
of
particles,
nm
particles (diameter 59 ± 5 nm) is
formed.
60
20
In theTable 3set
26
24
granulometric composition ofd < 100255
14
29
the complex (II) are presented.
36
119Apparently from Table 3,29
140nano sized particles of ReО3cub
100 < d < 200
245
9
164
with diameter 24 ± 5 nm wereobtained at step thermal decomposition of a complex (II) at the maximum temperature (255 0С).

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Conclusions

Electrochemical synthesis of complex Re with n-butanol (I) was carried out. It is establishedthat at Т = 200°С the complex (I) decomposes with formation of a mix of oxides ReO3 (cub) andReO2 (orth) in the condensed phase. Electrochemical synthesis of the complex Re with ethanol andisopropanol (1:1 mol/mol, membrane) (II) was also carried out. It was shown that at 255 0С it
decomposes with formation of ReO3 (cub).
Methods of obtaining of ultra dispersed (nano sized) oxide Re (VI) with d=24±5 nm andmixes of oxides Re (IV) and Re (VI) with d=59±5 nm were developed.
Acknowledgments: This work was supported by Russian Foundation for Fundamental Research(project no. 09-03-00328).
References

1. Palant А.А., Troshkina I.D., Chekmarev А.М. Rhenium metallurgy, 2007. М., «Nauka». p.298
2. Naumov A.V. Rhenium rhythms (review of world market), Nonferrous metallurgy transaction,
2007, V.6, P. 36-41.
3. Ryashenceva M. A., Minachev H. M. Renii i ego soedineniya v geterogennom katalize, M.:
Nauka, 1983. p.248.
4. J.Bregeault, B. El Ali, J. Martin, C. Martin, F. Derdar, G. Bugli, M. Delamar Novel rhenium catalysts(clorides and/or alkoxides dispersed on inorganic supports) for metathesis: a comparison with ammonium
perrenate precursors , J. of Molecular catalysis, 1988, № 46, P. 37-60

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6.5.
VOLATILE TECHNETIUM CARBONYL COMPOUNDS AND PROSPECTS
FOR THEIR APPLICATION
G.V. Sidorenko1, A.E. Miroslavov1, D.N. Suglobov1, A.A. Lumpov1, and A.N. Yalfimov2
1

Khlopin Radium Institute, Research and Production Association, Federal State Unitary Enterprise, 2-i Murinskii pr.
28, St. Petersburg, 194021 Russia
2
Russian Research Centre for Radiology and Surgical Technologies, St. Petersburg–Pesochnyi, Russia

The results obtained in synthesis and studies of volatile technetium carbonyl compounds (mainlyby the authors) are summarized. The main chemical forms of these complexes are considered:Tc2(CO)10 and its analogs, Tc(I) carbonyl halides, products of replacement of CO groups and halideions by other ligands, and technetium carbonyl hydrides. The results of studies of technetium
carbonyl complexes in the gas phase by IR spectroscopy and mass spectrometry are analyzed.
Vaporization of volatile technetium compounds is characterized by the preparative sublimation
conditions and temperature dependences of the saturated vapor pressure. Factors affecting thecapability of technetium carbonyl compounds for vaporization are discussed. The thermal stabilityof technetium carbonyl complexes is analyzed in the aspects of resistance to decarbonylation (forhigher carbonyls), loss of σ-donor ligands (for heteroligand complexes containing σ-donor ligands),
and deep degradation. Unique properties of β-diketonates as ligands for designing volatilecompounds are demonstrated.
The possibility of using technetium carbonyl compounds for chemical vapor deposition of
corrosion-resistant technetium coatings is examined. Such coatings can be of interest for protectionof certain units operating in seawater from biofouling. Samples of technetium coatings on model
supports were prepared from a large series of volatile carbonyl precursors. The chemical andphysical compositions of the coatings were determined, and their corrosion resistance in seawater
was evaluated. Some samples are not inferior to dense Tc foil in the corrosion resistance.
The volatility of technetium carbonyl compounds opens new prospects for their use in nuclear
medicine. First, transfer of the complexes through the gas phase allows preparation ofradiopharmaceuticals free of any foreign reagents and of finely dispersed carriers which may exert aside effect on the patient. Second, it becomes possible to perform chemical transformations in
nonaqueous media starting from higher technetium carbonyls, i.e., routes to compounds
synthetically inaccessible from the standard precursor, tricarbonyl triaqua complex[Tc(CO)3(H2O)3]+, are opened. Third, the volatility allows technetium compounds to be directly
used for diagnostics of respiratory organs with inhalation administration.
Technetium-99m pentacarbonyl iodide prepared by carbonylation of the eluate from atechnetium generator at a high CO pressure in the presence of HI and released into the gas phase in
the course of relieving CO pressure demonstrated selective and persistent accumulation in lungs oflaboratory animals at intravenous administration. This property, in combination with the volatilityof the complex and possibility of its inhalation administration, opens a unique possibility of using
the same agent for investigation of both ling perfusion and lung ventilation. The images of lungs oflaboratory animals, obtained with intravenous and inhalation administration of [ 99mTcI(CO)5], arepresented. However, additional studies are required to evaluate the selectivity of this agent inrevealing possible pathologies.

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6.6.
SYNTHESIS AND CHARACTERIZATION OF Ni-M (M = Pd, Pt)
NANOPARTICLE PAIR STRUCTURES
E.V. Abkhalimov, B.G. Ershov
Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Leninsky prosp. 31-4, Moscow, Russian Federation)

The process of interaction of nickel nanoparticles (Ni NPs) with ions of Pd(II) and Pt(II) was
studied. Bimetallic nanoparticle pair structures were synthesized.
The process was performed in two steps. The Ni NPs were synthesized through the chemical
reduction 2×10-4 M Ni2+ in water in the presence of the 1×10-4 M sodium polyacrylate (M. w. =2100 g/mol) by sodium borohydride.
Nickel ions reduction occurred instantly after adding of NaBH4, solution color changed toyellow. In ultraviolet range formation of the specific for Ni NPs absorption band at 215 nm wasobserved [1]. According to TEM, nickel nanoparticles were of spherical shape and narrow size
distribution with mean diameter 5 nm.
Interaction of Ni NPs with Pd(II) и Pt(II) led to formation of palladium and platinum
nanoparticles. Reduction of the metal ions took place at surface of the nickel nanoparticles.
According to the spectrophotometric data, reduced noble metal layers did not cover the entire
surface of Ni NPs. Gradual addition of Pt(II) was accompanied by significant increase of opticaldensity in the whole range of UV-VIS wavelengths. At concentration ratio Ni/Pt ≤ 2:1, formation ofshoulder at 220 nm in solution spectrum was observed.
Addition of Pd(II) resulted in progressive decrease of light absorption and scattering by thesolution. TEM and electron diffraction studies proved that synthesized bimetallic nanoparticles NiM (M = Pd, Pt) were of contact pair type.
Acknowledgments: The work was supported by Russian Fundation for Basic Research grant09-03-00432-а.
References:
1. B.G. Ershov, Izv. Akad. Nauk, Ser. Khim., №10: p. 1733 (2000).

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6.7.
Pd NANOPARTICLES IN AQUEOUS SOLUTIONS:SYNTHESIS AND PROPERTIES
R.D. Solovov1, P.A. Morozov2, B.G. Ershov2
1- M.V. Lomonosov Moscow State Academy of Fine Chemical Technology(Vernadskogo prosp. 86, Moscow, Russian Federation)
2- Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry andElectrochemistry of RAS (Leninsky prosp. 31-4, Moscow, Russian Federation)

Studies on two techniques of palladium nanoparticles (PdNPs) synthesis in aqueous solutions
were performed. PdNPs were synthesized through chemical reduction of dissolved of Pd2+ ions bygaseous hydrogen or photochemical reduction of dearated Pd2+ solutions by UV-VIS radiation of
xenon high-energy pulsed lamp. Process of photo-induced reduction was enhanced by using of
sodium formate as a source of reducing ∙COOH radicals in irradiated samples. Stabilizing agentsused were sodium polyphosphate (NaPP) and sodium polyacrylate (NaPA); both polymers were ofmolecular weight ~2100 g/mol.
H2-Process. Investigation of the effect of stabilizing agent concentration on PdNPs stability
proved that sodium polyacrylate was more preferred surfactant: the lowest concentration ratios
providing long-term stability of nanoparticles for [Pd2+]/[NaPP] and [Pd2+]/[NaPA] were 1:20 and
1:2.5 respectively. Studies of chemical reduction of Pd2+ with concentration up to 0.75 mM showedthat the initial concentrations of Pd2+ allowing to produce sedimentation stable nanoparticles wereas high as 0.5 mM; using of higher [Pd2+]0 values led to rapid precipitation of palladium black.
Furthermore, the sedimentation of PdNPs stabilized with NaPP was accompanied by particles
flocculation, what had not been observed in the similar experiments with NaPA solutions. The
atypically significant effect of [Pd2+]0 on sizes of hydrogen-reduced particles was revealed: at[Pd2+]0=0.35 mM mean diameter of Pd-NPs was 30 nm and at [Pd2+]0=0.50 mM it was 45 nm. Size
distributions and dispersity of PdNPs with both surfactants were found to be quite similar; howeverpolyacrylate-stabilized particles were 2 to 5 times more sedimentation-stable.
Photochemical process. The optimal concentration of sodium formate used in irradiationinduced reduction was found to be 10 times as high as Pd2+ concentration. Obtained PdNPs
exhibited narrow size distribution, Pd-NaPP and Pd-NaPA particles diameters were 2–7 nm and1.5–4 nm respectively (at [Pd2+]0=0.2 mM). The fact that Pd-NP synthesized photochemically wereof lesser size is explained by the difference of nanoparticles formation mechanisms – intensive
irradiation of solution results in instant formation of Pd seeds over the entire volume of sample,
while the interaction of H2 with Pd2+ takes place on the surfaces of a limited number of the mostactive nucleating centers.
Acknowledgments: The work was supported by Russian Fundation for Basic Research grant 0903-00432a.

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6.8.
WAVELET ANALYSIS OF EXAFS SPECTRA AS APPLIED TOPOLYNUCLEAR AND CLUSTER TRANSITION METAL COMPLEXES
V.Yu. Murzin,1,2 Ya.V. Zubavichus,1 M.V. Chukalina,3 A.A. Shiryaev,4 K.E. German4
1

National Research Centre "Kurchatov Institute", Moscow, Russia
A.V. Topchiev Institute of Petrochemical Synthesis RAS, Moscow, Russia
3
Institute of Microelectronics Technology RAS, Chernogolovka, Moscow District, Russia
4
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Moscow, Russia
2

Keywords: EXAFS, wavelet transformation, coordination compounds, clusters, nanoparticles,
technetium, rhenium, palladium
Abstract:

An approach to a qualitative analysis of EXAFS spectra based on the Morlet wavelet transformation
is extensively tested for a series of Re, Tc, and Pd reference compounds with variable coordination
environments of the central atom. A possibility of straightforward differentiation between MN(O)/M-Cl/M-Br/M-M (M=Pd, Re, or Tc) contributions in the first and second coordination shells
based on peak positions in 2D wavelet maps is demonstrated, which is extremely important as an
initial stage of EXAFS spectra interpretation prior to model construction and fitting. The potentialof this approach in structural studies of complex cluster species and nanoparticles is discussed.
Introduction

EXAFS spectroscopy is a very common experimental technique capable of retrieving local
structure information for functional materials irrespective of their aggregate state and degree ofstructural ordering therein [1]. Since 1970-s, the Fourier transformation is the most common way
for representing EXAFS spectra in a descriptive form [2]. Well separated coordination shells ofneighbors around a central atom appear as distinct peaks in the Fourier transform (FT), and thus
EXAFS FTs are often referred to as pseudoradial distribution functions in an analogy with atomic
pairwise distribution functions (PDF) [3] or radial electron density (RED) [4] obtained from total Xray scattering.
However, in those cases when a few groups of different atoms are located at similar
distances, their contributions in EXAFS overlap producing complex and difficult-to-interpret
interference patterns in FTs.
The wavelet transform (WT) represents an alternative and potentially more powerfulapproach to retrieve useful information from EXAFS spectra, as has been suggested quite recently
by M. Chukalina, et al. [5,6]. The WT has been widely used in different fields and applications suchas sound and image processing, data compression and digital signal de-noising [7]. When applied to
EXAFS data analysis, the WT is capable of providing not only radial distance information, but it
resolves data in k space as well giving a quick-glance estimate of the atomic number Z of anelement in a specific coordination sphere [8].

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Mathematical background

Fourier transformation
is given by:of a one-dimensional signal

defined over a finite value range(1)
The Fourier spectrum of the signal retains only its coordinate component, whereas themomentum component is lost. The use of windowed Fourier transform [9] partly overcomes thisdrawback. In the case of windowed Fourier transform, a
is analyzed only within a limited
window . The Fourier image is then given by:(2)
This implies that the signal is localized within a certain momentum range. Unfortunately, thewindow has a limited width independently of the specific scale of interest. Furthermore, the width isdescribed by different functions along the coordinate and momentum axes. In contrast, the wavelet
transformation automatically gives rise to a window effectively adapted to the signal being
processed, i.e., to main distance-frequency ontributions present in the spectrum [10].
The wavelet transformation is generally formulated as:
(3)
where

is the so-called mother wavelet function.

a)

b)

c)

Fig. 1.Examples of mother wavelet functions. a) WAVE, b) MHAT, c) Morlet.

A lot of such functions can be constructed [11] (Fig.1), but the Morlet wavelet is probably
one of the most efficient and widespread among them. The Morlet wavelet is given by [12]:(4)Essentially, the Morlet function is an amplitude-modulated sinusoid with a frequency , which isevanescent beyond a Gaussian of a specific half-width . It is evident that the dependence of the
wavelet signal on R becomes fully analogous to the Fourier transform at large . With a decreasein , the momentum resolution improves. An increase ingives rise to a worse resolution in k at
the costs of a better resolution in R, which implies that simultaneously high coordinate andmomentum resolutions remain elusive.
Experimental

Experimental EXAFS spectra of a series of rhenium, technetium, and palladium referencecompounds have been measured at the Structural Materials Science beamline installed at theKurchatov Synchrotron Radiation Source [13]. The electron storage ring Siberia-2 operated at anelectron energy of 2.5 GeV with an average current stored of 100 mA. A Si(111) channel-cut
monochromator was used to monochromatize the incident synchrotron beam. The spectra were
measured in the transmission mode using two ionization chambers filled with appropriate Ar-Xe
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gas mixtures before and after the sample. Preliminary processing of the raw EXAFS spectra has
been performed with Athena program from the IFEFFIT software package [14].
A dedicated software code WAVES (Wavelet Analysis & Visualization for EXAFS
Spectroscopy) has been developed to apply the wavelet transformation to normalized oscillatingparts of experimental EXAFS spectra. The code is written using the C++ API of the QT
programming environment. It reads the experimental background-subtracted unweighted oscillating
EXAFS signal as data input along with processing parameters, such as weighting power n, , ,ranges of interest in k and R spaces from a dialog window and then performs numerical integrationaccording to the above formulas.
Results

Fig. 2.Comparison of information content in FT and WT representations of Re L3 EXAFS for rhenium
chloroacetate Re2(Ac)4Cl2 with very short Re-Re bonds.

An illustrative example comparing traditional FT and the WT-based representations of an
EXAFS spectrum is given in Fig. 2, which concerns a dimeric rhenium chloroacetate complex [15].
In this complex, the coordination environment of each rhenium atom includes 4 oxygen atoms, 1
chlorine atom, and 1 rhenium atom at a very short distance of ca. 2.2 Å due to the formallyquadruple character of this metal-metal bond as schematically shown in Fig. 2 (lower left panel).
The Fourier Transform of the Re L3-edge EXAFS spectrum reveals two dominant peaks at around
1.5 and 2.0 Å, neither of which can be reliably attributed to a specific interatomic contact due to aheavy interference between the three contributions. In contrast, all three contributions, viz., Re-O,
Re-Cl, and Re-Re, are nicely resolved in the WT map. Furthermore, it becomes evident that both FT
peaks are actually dominated by the Re-Re contribution located at (14 Å-1; 1.75 Å) but the true
maximum of the Re-Re contribution occurs in the FT as an apparent deep between the two maxima
due to the interference with the Re-O and Re-Cl signals.

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Fig. 3. WTs of Re L3–edge EXAFS spectra for reference compounds with different coordination
environments of the rhenium atoms. From left to right: ammonium perrhenate (NH4)ReO4, pyridinium
hexachlororhenate (PyH)ReCl6, hexametthyleneiminium octachlorodirhenate (HMI)2Re2Cl8, and metallic
rhenium.

The high information content of WT maps is further verified in Figs. 3-6, which compare theWT representations of EXAFS spectra for an assortment of rhenium, technetium, and palladium
reference compounds. As it can be deduced from the graphs, the peak position corresponding to a
specific interatomic contact CA-N (central atom – neighbor) in the WT map is uniquely determinedby a combination of parameters ZCA, ZN, RCA-N, and 2CA-N. The “rule of thumb” for theinterpretation of the positions can be formulated as follows: a WT peak appear at larger k values forheavier CA-N pairs and for more rigid bonds characterized by narrow distance distributions (whichis equivalent to small values of the respective 2CA-N). For instance, the Re-O contributions forchloroacetate and perrhenate along the k axis occur at ca. 4 and 7 Å-1, respectively, which is due tothe effect of the Debye-Waller factors: Re-O bonds in perrhenate are more rigid than in acetate,
which is additionally characterized by low symmetry. On the other hand, in the series of puremetals, the M-M peak occurs at 8.5, 9.5, and 14 Å-1 for Tc, Pd, and Re exactly in a series ofincreasing atomic numbers.
These regularities also apply to the second-coordination-shell neighbors, as demonstrated by
the Pd…O (Pd-N-O) peak for tetranitropalladate and Pd…Pd (Pd-O-Pd) peak in palladium oxide.

Fig. 4. WTs of Tc K-edge EXAFS spectra for reference compounds with different coordination environmentsof the technetium atoms. From left to right: tetraphenylphosphonium pertechnetate (TPP)TcO4,
tetraethylammonium hexachlorotechnetate (TEA)TcCl6, tetramethylammonium hexabromotechnetate(TMA)TcBr6, and metallic technetium.

Fig. 5. WTs of Pd K-edge EXAFS spectra for reference compounds with different coordination environmentsof the palladium atoms. From left to right: palladium oxide PdO, potassium tetranitropalladate K2Pd(NO2)4,
palladium chloride PdCl2, and metallic technetium.
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Conclusions
The examples shown above clearly demonstrate that the WT is indeed a quite informative andinstructive way to represent EXAFS spectra prior to more thorough model-based quantitative
analysis. Elements with different atomic numbers Z (typically, from different rows of the Periodic
system) are characterized by clearly distinguishable positions along the k axis of the wavelet maps.
The wavelet representation is especially useful for complex and nanostructured materials with
mixed-ligand coordination of metal atoms.
Acknowledgments: The work was accomplished using the equipment of the Center for collective
use “Kurchatov Center for Synchrotron Radiation and Nanotechnology” supported by Russianfederal contract 16.552.11.7003.
References
1. Y. V. Zubavichus, Yu. L. Slovokhotov. Russ. Chem. Rev. 70, 373-403 (2001).
2. F.W. Lytle, D.E. Sayers, E.A. Stern. Phys. Rev. B 11, 4825–4835 (1975).
3. T. Egami, S.J.L. Billinge (Eds.). Underneath the Bragg peaks. Structural analysis ofcomplex materials. Pergamon, Amsterdam, 2003.
4. E.M. Moroz. Russ. Chem. Rev. 80, 315-334 (2011).
5. H. Funke, A.C. Scheinost, M. Chukalina. Phys. Rev. B 71, 094110 (2005).
6. H. Funke, M. Chukalina, A.C. Scheinost. J. Synchr. Rad. 14, 426-432 (2007).
7. Q. Tao, V.I. Mang, X. Yuesheng (Eds.). Wavelet analysis and applications. BirkhäuserVerlag, Basel, 2007.
8. J. Timoshenko, A. Kuzmin. Comp. Phys. Commun. 180, 920–925 (2009).
9. D. Gabor. J. IEEE 93, 429-457 (1946).
10. I.M. Dremin, O.V. Ivanov, V.A. Nechitailo. Physics-Uspekhi 44 447–478 (2001).
11. N.M. Astafieva. Physics-Uspekhi 39 1085–1108 (1996).
12. P. Goupillaud, A. Grossman, J. Morlet. Geoexploration 23, 85-102 (1984).
13. A.A. Chernyshov, A.A. Veligzhanin, Y.V. Zubavichus. Nucl. Instr. Meth. Phys. Res. A 603,
95-98 (2009).
14. B. Ravel, M. Newville. J. Synchrotron Rad. 12, 537-541 (2005).
15. P.A. Koz'min, M.D. Surazhskaya, T.B. Larina, A.S. Kotel'nikova, T.V. Misailova, Koord.
Khim. 6, 1256-1258 (1980) [In Russian].

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6.9.
NANODIAMONDS FOR BIOMEDICAL AND SORPTION APPLICATIONS:STRUCTURE AND DEFECTS
A.A. Shiryaev
Institute of Physical Chemistry and Electrochemistry, RAS, Leninsky pr. 31, Moscow 199991, Russia;
shiryaev@phyche.ac.ru

Nanodiamond (ND) particles belong to a broad family of nanocarbon-based materials with astructural diversity that is based on specific synthesis conditions, post-synthesis processes, andmodifications. ND particles with sizes up to several tens of nanometers currently find broad
application in polishing, structural materials, and lubricants, as well as prospective applications inbiotechnology and medicine.
Recently, several important new application areas have been proposed based on the potential ofincorporating impurity atoms and point defects into the nanoparticle lattice. Major breakthroughareas where controlled doping of NDs and on-demand production of the nitrogen-vacancy (N-V)
centers. The spin state of the negatively charged N-V center can be polarized by optical pumping
and can be manipulated using microwaves, permitting implementation of an efficient single photon
emitters for quantum information processing or a magnetic sensor with a nanoscale resolution.
Optical transitions in the N-V centers in diamond provide bright and stable photoluminescence.
We have recently shown that very small nanodiamond particles (1-2 nm) may also possess brightluminescence from another defect - Silicon –Vacancy complex (Si-V) [1]. Thus, on-demand
production of the N-V and Si-V centers in nanodiamond is of paramount importance for quantum
information processing and quantum computing, nano-scale imaging magnetometry andphotoluminescent probes for bio-research. We will discuss recent advances in understanding defects
and structural peculiarities of nanodiamonds, important for various applications.
Another important and yet not fully explored niche for nanodiamonds is their application as
sorbents. Various ways of surface modification are invented, thus allowing creation of efficient,durable and reusable nanodiamond-based sorbents. Recent results on radionuclides sorption will bereported.
References:
1. Shiryaev et al., Geochim. Cosmochim. Acta. 75, 3155-3166 (2011)
2. Vlasov et al., Small 6, 687-694 (2010)

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6.10.
NANOTECHNOLOGIES IN RADIOCHEMICAL TECHNOLOGY AND
RADIOECOLOGY INCLUDING TECHNETIUM SPECIATION AND
SEPARATIONS
Tananaev I.G., K.E. German
Frumkin Institute of physical chemistry and electrochemistry of RAS, 119071, Moscow, Leninsky
prospekt, 31/4, geokhi@mail.ru
Modern approaches to sustainable development of Atomic Energy, development andimprovement of nuclear fuel cycle in Russia are directly linked to the development of nanoindustry.
The following items will be elucidated and discussed herein: major scientific advances in the
production of nuclear fuel compositions, search of new technologies for the reprocessing of spent
nuclear fuel (SNF) and optimization of existing ones, the solutions of the problem of radioactive
waste of different activity levels management, development of radioecology. Information about
search results in getting of oxide fuel modified compositions will be presented in the report also.
The results on the synthesis and use of heterogeneous catalysts based on noble metal nanoparticles
drawn on the carrier surface to improve processing of SNF also will be presented. The advanced
technologies of water low-acid and fluid (in liquid CO2) dissolution of uranium and plutoniumoxides resulting in significant decrease of radioactive waste volume will be also considered.
With respect to nuclear waste treatment we shall discuss the major results for processing
both liquid (water/organic) and gaseous wastes using nanocollectors for cleaning of industrial drain
productions, pieces of carbon materials (activated and modified coals, nanotubulens), as well assorbents for fixing of various forms of radioactive iodine based on Ag nanoparticles, respectively
key results in producing the above mentioned carbon materials, including development of methodof electron-beam conversion of ligno-cellulosic material to obtain nanoporous coals with unique
physical and chemical properties will be presented. Also the data on processing of alkali radioactive
material handling, methods of improvements of various solid matrixes (cement compounds, glass
composition, ceramics materials) by method of nano-additives for immobilization of high-level
waste will be proposed.
In the end of the report data on development of methods of radionuclides and espessially
technetium-99 determination and concentration in environmental media objects using
nanostructured high-performance agents – extractans and sorbents will be given. On the basis of theinformation submitted will provide key conclusions on advisability and development of researches
in the field of nanoindustry in radiochemical technology and radioecology.
Acknowledgments: The work was partially supported by the Russian Foundation for Basic
Research (Projects № 09-03-00017).

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6.P1.
HIGH TEMPERATURE INTERACTION OF RHENIUM, MOLYBDENUM
AND TUNGSTEN WITH URANIUM MONONITRIDE
G.S. Bulatov, K.N. Gedgovd, D.Yu. Lyubimov1.
Institution of Russian Academy of Sciences – A.N. Frumkin Institute of Physical Chemistry andElectrochemistry of RAS (Leninsky prosp. 31-4, Moscow, Russian Federation)
1
ENTERPRISE OF “ROSATOM” - FEDERAL STATE UNITARIAN ENTERPRISE “SCIENTIFIC RESEARCHINSTITUTE SCIENTIFIC INDUSTRIAL ASSOCIATION “LUCH”(24, Zheleznodorozhnay st., Podolsk, Moscow region, Russian Federation)

Keywords: nuclear fuel, uranium mononitride, rhenium, molybdenum, tungsten, diffusion
coefficients
Abstract:
The interaction between uranium mononitride and refractory metals: rhenium, molybdenum andtungsten at the temperature 1773 were investigated.
Diffusion coefficients of uranium from UN into Re, Mo and W in different structure state(polycrystalline and single crystal metals) have been estimated. The acceleration of uranium
diffusion into the depth of the polycrystalline metals was associated with the diffusion at the grainboundaries.
Introduction
The study was aimed to research the new materials for the utilization in high temperature nuclear
devices and to increase their efficiency and safety [1].
Experimental
The interaction of nitride nuclear fuel U(N0.90 C0.05 O0.07)1.02 with rhenium, molybdenum andtungsten metals acting as cladding materials at T=1773 K was investigated. Uranium in the fuel wasenriched in 235U to 90 %. Uranium nitride and metal samples in a form of the disks, possessing 2 -3mm thickness and 8 – 9 mm diameter were placed in turn into the rhenium, molybdenum andtungsten metal ampoules. The ampoules were welded in vacuum and annealed in the vacuum
furnace at 1773 K for 1000 hours. The diffusion coefficients of uranium from UN to Re, Mo and W
were determined using layer by layer radiometric analysis, measuring the integral α-activity ofmetal samples. The diffusion coefficients values were calculated in terms of diffusion model for theconstant source to the semi-infinite body using the equation [2]:Ii / Io = erfc [x i / 2(Dt)1/2],
where: Ii - integral α-activity on the depth xi, Io - integral α-activity on the depth x0=0,
D - diffusion coefficient, t – time.
Results and Discussion
The interaction of uranium mononitride with these metals at 1773 K was accounted for the diffusionof the fuel components to the metal samples (Fig. 1-3). Using autoradiography technique thedifference in the diffusion mechanism for single crystals and polycrystalline samples was
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1

1

0,9

0,9

0,8

0,8

0,7

0,7

0,6

0,6

0,5

I/Io

I/Io

stablished. The acceleration of uranium diffusion into the depth of the polycrystalline metals was
associated with the diffusion at the grain boundaries (Fig. 1).

1

0,4

a

0,5
0,4

0,3

0,3

2

0,2

0,2

0,1

0,1

0
0

1

2

X, mkm

3

4

0

5

0

10

20

30

40

50

60

mkm
X,X,μmFig. 1. Radiometric curves for polycrystalline–1 (with a - autoradiography of diffusion
U→Re, ×200, X=5 μm) andsingle crystal – 2 rhenium samples
1
0,9
0,8
0,7
0,6
I/Io

The corresponding diffusion coefficients values
for uranium into polycrystalline (D1) and single
crystal samples (D2) were determined as:
D1 (U→Re) = 1.2 × 10-18 m2×s-1,
D1 (U→Mo)= 3.7 × 10-16 m2×s-1,
D1 (U→W) = 9.8 × 10-20 m2×s-1,
D2 (U→Re) = 4.0 × 10-19 m2×s-1,
D2 (U→Mo)= 4.9 × 10-17 m2×s-1
D2 (U→W) = 3.3 × 10-21 m2×s-1.
The presented data prove that the diffusion
factors for uranium from UN to rhenium metal
were lower than corresponding values formolybdenum and higher than for tungsten metals.

Fig. 2. Radiometric curves forpolycrystalline -1 andsingle crystal- 2
molybdenum samples

0,5
0,4
0,3
0,2

1

0,1
0
0

0,5

21

1,5

2

2,5

X, mkmFig. 3. Radiometric curves forpolycrystalline - 1 andsingle crystal – 2tungsten samples

Conclusions.
The presented results may be taken into account in the development of the fuel elements based onuranium mononitride for their utilization in the high temperature reactors for ground and space
installations.
References.
1. V.P. Nikitin, B.G. Ogloblin, E.N. Sokolov. Atom. Energ. 88: 95-108, (2000).
2. Bokschtein B.S. Diffusion in Metals, Metallurgiya: Moscow, (1978), 248 p.

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6.P2.
THERMAL BEHAVIOR OF PERRHENATE COMPLEXES OF
NEODYMIUM AND PREPARATION OF NANODIMENSIAL RHENIUM
CERMETES
A.M. Fedosseev, A.A. Bessonov, Ph. Moisy*
IPCE RAS, Moscow, Leninskii pr.31- 4, 119071 Russia ( e-mail: fedosseev@ipc.rssi.ru)* - CEA – Marcoule, DEN DRCP, BP17171 – 30207, Bagnols sur Ceze, France

Trivalent f-elements perrhenate are proposed as promising precursor agents for cermet
composites preparations. Regarding the targets for minor actinides and technetium incineration, thecermet composites are noted as the materials with the best thermal conductivity that can help toreduce the operating temperature. In this work efforts were focused in finding an original approachfor their easy production. We propose a method of molecular Re(Tc)-Nd2O3 cermet preparation,
where the rare earth element may serve as an analogue for americium and rhenium as an analogue
for technetium, which transmutation should also be considered. For a complete understanding of thedegradation process of the perrhenates under reductive conditions, thermoanalytical diagrams ofNd(ReO4)3 .4H2O and Eu(ReO4)3 .4H2O have been recorded in this work. These compounds
originally contain four water molecules and the dehydration mechanism proceeds via similar
schemes. Rhenium reduction with 6%H2/Ar occurs at least in three stages distinctly observed in the
TG profile of europium compound. The first reduction step starting at 430oC, is followed by a stepat 590oC and a last one around 620oC. This thermodiagram profile leads to the conclusion that
perrhenate reduction occurs via ReO3 and ReO2 intermediates to finally reach the metallic Re.
Based on the thermogravimetric data, the temperature for Nd2O3-Re cermet preparation may beestablished at 590-600oC.
100

 Re metal90* Nd2O3 CUB

80

Intensity, a.u.



*

70



60





50
40

*

30
20

a


*

*  b



*

*



*  c

10
0
10

20

30

40

50

60

70

2o

X-ray powder diffraction patterns of samples
obtained at this temperature show line
broadening, obviously due to the low metal
crystallinity in the nanodimensional cermetmaterial. Nevertheless, the lines corresponding
to rhenium metal as well as to cubic Nd2O3
may be unambiguously identified. Increasingof the heating time at this temperature leads tovery slow nanocrystalline cermet particles
recristallization. SEM, EDX and EDS spectra
confirm clearly the high degree of distributionof the primary components in the cermet
product.

X-ray diffraction patterns of Nd2O3-Re cermet
prepared at 600 oC: a: 1 hour, b: 4 hours, c: 10
hours

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6.P3.
TECHNETIUM(VII) SORPTION BY MODIFIED NANODIAMONDSFROM AQUEOUS AND NITRIC ACID SOLUTIONS
Ya.A. Obruchnikova, A.A. Shiryaev, A.M. Safiulina, A.V. Karpukhin1
I.I. Kulakova1, K.E. German
Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Leninsky prosp. 31-4, Moscow, Russian Federation)
1
Lomonossov Moscow State University, (Leninskie gory, 1, Chem. Dept., Moscow, Russian Federation)

Nanodiamonds (ND) produced by detonation of high-energy explosives in oxygen-deficientenvironment present considerable interest for studies of nanoparticles and are also important fornumerous applications in diverse fields ranging from tribology and photonics to biomedicine [1].
Many chemical properties of NDs are determined by surface radicals and currently various types of
surface functionalisation are considered [2].
Technetium is a nuclear fission product and its reprocessing is often performed in intense radiation
fields, precluding long-term use of many conventional ion-exchangers. High radiation stability of
NDs may open new exciting possibilities for their applications in radiochemistry [3]. In our work
we have studied Tc sorption on detonation nanodiamonds treated in different ways to modify
surface radicals. The sample #1 represents NDs sintered at High Pressures – High Temperature
conditions. The sample #3 is commercially available ND powder subjected to primary acid cleaning
procedure after detonation. Such samples usually consist of very stable aggregates of ND grains.
Whereas the size of the individual ND grains is 4-5 nm, the size of the aggregates lies between
several tens to hundreds nanometers. Destruction of these aggregates is notoriously difficult. The
sample #7 represents the disaggregated ND sample [4], i.e. it consists of individual 4-5 nm diamondparticles. Its surface chemistry was not specially studied, though it is clear that it is dominated byvarious H- and O- containing radicals. The surfaces of the samples #2, 4-6 was modified bychemical and physical oxidation, see Table 1. The nanodiamond powders were ultrasonicated atambient conditions. 10-4M Tc in H2O and HNO3 solutions were prepared for sorption tests, thesorption efficiency was determined by -LSC activity measurements of the solutions.Two samples(#2 – with surface aminogroups and #4 – heated in H2 atmosphere at 800 C) showed high efficiency
towards Tc(VII) sorption. Their sorption efficiency is comparable to the best anionites. The ionicstate of Tc in these solutions is anion pertechnetate TcO4- and the most probable sorption
mechanism should be anion exchange at the surficial cationic positions.
Table 1. Description of samples of detonation nanodiamonds
Sample No
Diamond treatment
1
Sintering at HPHT
2
HPHT sintered and aminated (NH-C18H37)
3Standard industrial cleaning by HNO3
4Heated in Н2, 800 оС, 5 h
5Oxidized by air at 450 оС
6
Oxidized by HNO3+H2SO4
7
Disaggregated
References.

Fig. Distribution coefficientsfor sorption of Tc(VII) by
modified nanodiamonds.

1. V.Yu. Dolmatov, Russ. Chem. Rev. 76: 375-397.
2. I.I. Kulakova, Solid State Physics 46: 621-629 (2004).
3. S.I. Chukhaeva, L.A. Cheburina, Superhard materials (Russ.) 2: 43-48(2000).
4. A. Kruger et al., Carbon 43: 1722-1730 (2005)

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6.P4.
STABILIZATION OF NANO-RHENIUM AND NANO-TECHNETIUM
IN AMORPHOUS CARBON MATRIX.
K.E. German1, M.S. Grigoriev1, A.Ya. Maruk1,2, Ya. V. Zubavichus3,
V.Yu. Murzin3, Ya.A. Obruchnikova1,4, A.A. Shiryaev1

1 - Institution of Russian Academy of Sciences - A.N. Frumkin Institute of Physical Chemistry and Electrochemistry ofRAS (Leninsky prosp. 31-4, Moscow, 119071 RF)
2 - Burnazyan Federal Medical Biophysical Center of FMBA Russia; 123182, Moscow, Zhyvopisnaya,46;
amaruk@list.ru

e-mail:3 – National Research Center “Kurchatov Institute” (Kurchatov sq.1, 123182 Moscow, Russian Federation)
4 - D. Mendeleyev University of Chemical Technology of Russia, Miusskaya Sq. 9, Moscow 125047, Russia.

Keywords: technetium metal nanophase, rhenium metal nanophase, technetium carbide, rhenium carbide,
amorphous carbon matrix
Abstract
Metallic rhenium or technetium nano phases could be generated by thermal decomposition of
perrhenates/pertechnetates of organic cations under argon, the parallel carbonization of the cations provides
conditions favorable for formation of nano- and microparticles of Re and Tc carbides. For
hexametileniminium and thriphenylguanidinium pertechnetates the conversion proceeds with Tc 6C
formation. In the thermal decomposition of triphenylguanidinium perrhenate only a mixture of Re metal, Re
carbide and free carbon is formed. The nanocrystalline phases were X-ray amorphous, while formicrocrystalline Tc6C phase the cubic lattice with a = 3.98 Å was deduced. For the annealed sample thedetermined parameter a = 5,095 Å and the sp.gr. Pm3m indicates that the new Re carbide phase isisostructural with a number of Ln carbides.
Introduction
The noble metals and also Re were considered till recently to have no or very small affinity to carbon[1]. The formation of a carbide TcC1-x with low content of carbon (x = 0.83) was proved [2,3] also indicating
low affinity of Tc to carbon. Small amounts of carbon were shown to react readily with Tc metal causing its
crystallographic distortion from HCP to orthorhombic structure and important enlargement of the specificunit cell volume [3]. This was confirmed by findings of distorted Tc metal and Tc carbide in thermal
decomposition product of Tc carbonyls [4]. In this work we employ in situ carbonization in course ofthermal decomposition of several organic pertechnetates and perrhenates aimed at the preparation oftechnetium and rhenium carbides.

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Results and discussion

The thermal decomposition of Tc and Re compounds taken as initial salts or supported at the-Al2O3 as an inert ceramic carrier was studied in this work. In the first case the metals were microparticulated and when the initial compounds underwent the fusion before the decomposition,
macroagregates of metal or carbide phases were observed.
In the second case the nanophase Tc and Re metals or carbides were prepared depending on
the nature of the cation and the macroparameters of thermolyses.
Under the conditions favoring metal Tc formation, the phase was initially X-ray amorphous.
But the EXAFS analyses of the sample gave evidence for pure metal phase (Fig.1).

1.4 Tc-C 1.76Å
6.0 Tc-Tc 2.72Å

|FT(k (k))|

TcCx
3

12 Tc-Tc 2.72Å

Tc
0

1

2

3

4

5

6

R, Å
Fig.1. Tc K-edge EXAFS spectra of nanostructured Tc metal and carbide prepared bythermal decomposition of hexametyleniminium pertechnetate represented as Fourier (left) andWavelet transforms.
Hexametyleniminium pertechnetate and triphenylguanidinium pertechnetate at 600 K in Ar
gas undergo conversion to X-ray amorphous technetium carbide that could be stabilized inamorphous carbon matrix. Annealing of this product at 1073-1673 К leads to recrystallization and
FCC structure with a = 3.98 Å forms.
Hexametyleniminium perrhenate and morfolinium perrhenate undergo conversion at 700 K
in Ar gas to X-ray amorphous rhenium metal that is recrystallized under the subsequent annealing at
1073-1673 К to form HCP structure. Nanophases supported at the -Al2O3 were X-ray amorphous.
In the thermal decomposition of TPGHReO4 only a mixture of Re metal, Re carbide and freecarbon is formed. The product was solid-foam shaped. The principle product was a new phase ofrhenium carbide that was not described earlier. This was evidently due to higher concentration of
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carbon in the products of organics thermal decomposition. Small-angle X-ray scattering shows thatthe mean particle diameter was 16 nm. EXAFS pattern of the product reveals a strongly disordered
local environment around Re atoms, which can be described by a set on non-equivalent Re-C and
Re-Re bonds. (Fig.2).

0.3 Re-C 2.14Å
1.0 Re-C 2.46Å
1.1 Re-Re 2.62Å
3.1 Re-Re 2.73Å

|FT(k (k))|

ReCx
3

12 Re-Re 2.75Å

Re
0

1

2

3

4

5

6

R, Å
Fig. 2. Re L3-edge EXAFS spectra of nanostructured Re metal and carbide prepared by thermal
decomposition of triphenylguanidinium perrhenate represented as Fourier (left) and Wavelet
transforms).
Table 1. X-ray diffraction pattern of new Rhenium Indexing of the XRD pattern yielded
carbide phase (а = 5.095 Å) formed in thermal parameter a = 5,095 Å with no systematic
decomposition of TPGHReO4 at 623 K followed by absences consistent with the sp.gr.
Pm3m, which indicates that the Re
annealing at 1273-1373 K in argon [5].
carbide phase is probably isostructural toa number of Ln carbides (Ho3C, Sm3C)
[7].
No
HKL
2Theta2ThetaDiffer.
This observation suggests that the(exp.)(calc.)
usual inactivity of Re towards C is only
due to very high melting temperature
1
202
50.70
50.6040.096
rather than total absence of affinity.
2
311
60.30
60.1530.147
Indeed, when Re metal is generated insitu as a nano-phase simultaneously with
3
400
74.26
74.374- 0.114active carbon formed by organic cations
4
233
90.20
90.266- 0.66
thermolyses, both components are highly
reactive and thus able to form Re carbide
5
404
117.60117.5420.070
phase.

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Gaseous products of the thermolyses imply the oxidative mechanism of the destruction (CO 2, H2O anddifferent organic fragments of cations).

Fig.3. Laser microanalisis mass
spectrum registered with the LAMMA1000 instrument from the product ofthermal decomposition of TPGHReO4
at 623 К followed by isothermal
annealing at 1273-1373 К in Ar gas
atmosphere [5].

The laser evaporation of the Re-RexC-C composite formed by 5 thermolyses in LAMMA-1000
instrument has given evidence for ReC+, ReC2+ and ReC3+ ions formation (Fig.3) while the same analyses of
non-thermolysed 5 indicated just the first two peaks (185 and 187) presence. This is indicative ofconsiderable affinity of Re to C not only in solid but also in gas phase under such conditions.

Conclusion.
Metallic rhenium or technetium nanophase could be generated by thermal decomposition of
perrhenates/pertechnetates of bulky organic cations under argon, the parallel carbonization of the cation
provides conditions favorable for Re and Tc carbide formation as nano and microparticles. For
hexametileniminium and thriphenylguanidinium pertechnetates the conversion posess Tc6C with a facecentred cubic structure. In the thermal decomposition of triphenylguanidinium perrhenate, just a mixture of
Re metal, Re carbide and free carbon is formed. XRD patterns of nano dimension phases were X-ray
amorphous, while for micro dimension Tc6C phase the cubic lattice with a = 3.98 Å was deduced. For
annealed sample the determined parameter a = 5.095 Å and the sp.gr. Pm3m indicates that the new Re
carbide carbide phase is isostructural to a number of Ln carbides.

Acknowledgments: The work was supported by RFBR grant 09-03-00017. EXAFS studies were performed
using the equipment of the centre for collective use “Kurchatov Centre for Synchrotron Radiation andNanotechnology” supported via Russian Federal contract 16.552.11.7003

References.

1.
2.
3.
4.

5.

T. Oyama (Ed.), The Chemistry of Transition Metal Carbides and Nitrides, Blackie Academic andProfessional, London, 1996.
H. R. Heines, P. C. Mardok, and P. E. Potter, Plutonium 1975 and other Actinides, Proc.: 5th Int. Conf.
(Baden Baden, 1975). Amsterdam, 233-244 (1976).
K. E. German, V. F. Peretrukhin, K. N. Gedgovd, etc., Journal of Nuclear and Radiochemical Sciences, 6:
211-214 (2005).
G.V. Sidorenko, A.E. Miroslavov, D.N. Suglobov. Radiochemistry. 51: 583-584 (2009).
K. E. German. Nuclear Medicine and Biology, (2010) 37, Iss. 6, P. 687.
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6.

7.

K. German. In situ carbonization for rhenium and technetium carbide nano and micro phase preparation.
Proceedings of the International Symposium on Technetium and Other Radiometals in Chemistry andMedicine – Forum Brixen – BressanoneCongress Center (Italy) September 8-11, 2010, pp.125 -128.
K.A. Schneider and F.W. Calderwood. Journal of Phase Equilibria, 7: 445-446 (1986)..

6 th SECTION – NANOTECHNOLOGY OF Tc AND Re
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6.P5.
ION SELECTIVE ELECTRODES BASED ON MONOCRYSTALLINE
KTiOPO4 WITH NANOCAPILLAR CONDUCTIVITY FOR
DETERMINATION OF K+-IONS.
A.V. Kopytin, Yu. A. Politov, E.G. Ilyin, Yu.I. Urusov, K.E.German.
IGIC RAS, MUCTR, IPCE RAS ( ionix@igic.ras.ru)
ABSTRACTNew improved K+–selective electrode based completely on solid single crystal KTP with
nano-capillary conductivity is developed. The crystal KTP grown by two different methods had an
ordinary orthorhombic structure (Pna21) with the chain structure of shared TiO6 octahedrons, wherethe vacantly mobilized K+ ions provide the ionic conductivity through nano-dimension capillary.
The membranes of 0.8 mm thickness and 6 mm diameter were hermetically sealed without gluematerials into a IONIKS 111.080 solid membrane electrode body together with an inner standard
Ag/AgCl reference electrode. The electrode presents linear response in the range of pK +=1 – 5, theelectrode function slope S=58.8±0.4 at 25o C and high selectivity coefficients for ions of alkali andearth-alkali elements that permits to use it for practical application in medicine. The electrode had aconvenient response time, DLK of pK+ = 5.2 ± 0.1 and the reproducibility of electrode potential ±0.2
mV in KNO3 solutions during at least 28 months. Investigation of a unique properties a single
crystal KTiOPO4 (KTP) and the design of new improved K+–selective electrodes based completely
on KTP are reported. The studied single crystal KTP were grown by using of two methods:
hydrothermal and melting from a solution . They had ordinary orthorhombic structure (Pna21) withlattice parameters: a=12.814, b=6.404 and c=10.616 Å, and the chain structure made of TiO6octahedrons, where the potassium ions were able to move by vacancy mechanism, providing ionic
conductivity.. The membranes of 0.8 mm thickness and 6 mm diameter were hermetically sealed ina IONIKS 111.080 solid membrane electrode body without glue materials. The 0.01 M KCl
solution and a standard Ag/AgCl electrode were placed inside of reservoir. The electrode response
was linear in the range of pK+=1 – 5, with the electrode function slope equal to S=58.8±0.4 at 25o
C. The high selectivity coefficients for ions of alkali and earth-alkali elements were found. The
selectivity of proposed electrode permits to use it for practical application in a medicine. The
electrode had a convenient response time, DLK of pK+ = 5.2 ± 0.1 and the reproducibility ofelectrode potential ± 0.2 mV in KNO3 solutions during at least 28 months.
Introduction
Ion-selective electrodes for determination of potassium are among the most used in clinicalchemistry and agriculture. In this connection the increase of measurement precision by
improvement of electrodes parameters remains an important task. This purpose may be achieved inseveral ways: the improvement of ion-selective electrode construction, the improvement of separate
units quality, the optimum selection of membrane composition (with already known components),
the search of the new electrodoactive components, as well as the new sensitive elements –membranes (from inorganic materials).
The several kinds of K+-selective electrodes with membranes of a various compositions areat present developed and produced. All of them are assigned to a type of electrodes on the basis ofneutral carriers and are described in monographs and reviews [1-2]. The well known and received
the wide use is the electrode based on valinomycin [3], which is included in production catalogs ofmany firms, engaging by production of ionometric equipment. Therefore in our work we comparedparameters of new electrode based on monocrystal with valinomycin electrode.
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Theoretical premises
The requirements to membrane materials were formulated yet in the middle of 60’s. In spiteof it, untill now the electrode based on LaF3 remained the only electrode with monocrystal
membrane. Use of LaF3 as a monocrystal is indispensable condition to obtain the electrode withhigh analytical parameters. The active search of monocrystals with high ionic conductivity(basically 60's–beginning of 70's) as membranes ion-selective electrodes had no positive result.
The first message on an opportunity of application of monocrystal KTiOPO4 (KTP) as amembrane K+ - selective electrode has appeared in 1994 [4].
For the first time a monocrystal of KTiOPO4 (KTP) was identified by French researchers in1971 [5] and was patented in 1974 for use in electrooptical devices, converting the frequentcharacteristics of laser radiation [6]. The monocrystal KTP has an orthorhombic structure andconcerns to point group mm2 (space group Pna21). For KTP lattice parameters are: a=12.814 ,b=6.404 and c=10.616Å. Each elementary cell contains 8 formula units. The structure ischaracterized by chains of TiO6 octahedrons, which are connected on two corners and the chains are
divided by PO4 tetrahedrons. Potassium ions, located in centers of high coordination number, areweakly bound to oxygen atoms, which surround of atoms titanium and phosphorus, and are able tomove by vacancy mechanism. For the first time the information about low-temperature ionic
conductivity of KTP crystals has appeared at the end of 80's [7]. Data, obtained by various authors
have shown, that electrical conduction in KTP in a wide range of temperatures occurs almost
exclusively through the movement of potassium ions on channels, which perforate a framework
along an c axis. Electron and anion conductivity are more isotropic and their summary upper limit
can be evaluated from resistance of a crystal in perpendicular directions to c axis. According towork *197* this resistance makes about 1012 om.cm that on 6 - 7 orders of magnitude higher thanresistance of a KTP crystal in a direction along the axis c with under conditions of cation transport.
Thus, it is possible to conclude about overwhelming character of cation conductivity KTP. Researchof impedance has allowed to establish, that greatest value of ionic conductivity of crystal was
1.2.106 om.cm [8]. Taking into account availability of low-temperature ionic conductivity and statestability, assumption about a opportunity of use of a KTP crystal (by analogy with LaF3) as amembrane of K+–selective electrode was made.
Experimental section
1. Equipment and procedure.
All measurements were carried out with use of a ionmeter Orion Research Model-901(USA). The external reference electrode was a IONIKS-112.024 (Russia) double-junction Ag/AgClelectrode with 1M potassium chloride and 1M lithium sulfate brige electrolyte. Electroanalitycal
parameters of ion–selective electrode were measured according to IUPAC recommendations [9].
The selectivity coefficients were measured by the method of mixed solutions.
2. Synthesis of membrane and the electrode design.
KTP crystals were grown by two methods: hydrothermal and from a solution in melt
[10,11]. The conductivity of crystals varied in a range of 107—106 om.cm. The membranes of about
0.8 mm thickness and about 6 mm diameter were mounted in a IONIKS 111.080 solid membraneelectrode body, in which the hermetic sealing of a membrane was made without glue materials. The
0.01 M KCl solution and a standard silver/silver chloride electrode were placed inside of reservoir.
3. Reagents.
In this work the standard reagents of the grade “chemically pure” Reakhim (Russia) wereused. All standard solutions was prepared using deionized water.
Results and discussion
A typical electrode characteristic of monocrystal K+–selective electrode is given in fig.1.
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The linear response of electrode potential was observed in a wide range of concentration
1 – 5 рК+. The electrode function slope was close to theoretical one and was equal S=58.8±0.4 at
25o C.

Fig.1 Response of K+ - Selective electrodes.
The coefficients of selectivity for ions of alkali and earth-alkali elements are represented intable 1.
Table 1. Coefficients of selectivity of K+ -selective electrodes.
+

+

Ион

H

Li

-lgKi

2.2

2.6

+

+

+

Na

Rb

Cs

3.4

1.5

3.2

2+

2+

2+

2+

Mg

Ca

Sr

Ba

NH4

3.3

2.8

1.5

2.1

1.1

+

A correlation between ionic radius and selectivity coefficient is shown at fig.2.
As follows from this figure, the size of a channel probably plays an essential role inselectivity, in which ionic transport of ions take place. So, when going from potassium to sodium
ion selectivity changes almost on three order of magnitude. The figure 3 evidently demonstrates thedifference in selectivity between proposed electrode, glass electrode ESL-47-07 (Belarussia) andvalinomycin electrode Potencial (Russia).
The measured limit of detection in pure potassium nitrate solutions was 5.8 pK+.
Reproducibility of electrode potential in potassium nitrate solutions was not worse than 0.2 mV.
The changes analytical parameters were not observed for a time of the study (14 months).

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Fig.2 Correlation between ionic radius and selectivity coefficient.

Fig.3. Lg K (a – glass electrode, b - КТР, c – valinomicine electrode).
Working mechanism of this membrane is not yet investigated, and we hope, that the further
study of the electrode characteristics will show that proposed crystal is a unique one as a ionselective membrane.
Summary
Inorganic material as a membrane of potassium-selective electrode has been proposed. This
material represents a monocrystal of KTiOPO4, having an orthorhombic structure. The
characteristics of proposed electrode have been investigated. It has been found, that developed
electrode have high selectivity in the presence of alkali and earth-alkali ions, comparable with thatfor electrode based on valinomycin. At the same time high selectivity for potassium in the presence
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011of rubidium and cesium ions was noticed. Electrode characteristic is linear in a range pK+1 - 5 at atheoretical slope.
References
1.
2.
3.
4.
5.
6.
7.
8.

9.

Корыта И., Штулик К. Ионоселективные электроды. М. Мир.: 1989.С.206.
Moody G.J., Thomas J.D.R. // Ion-Selective Rev.1979.№1.P.3
Frant M.S., Ross J.W.// Science.1970.№167.P.987
Буслаев Ю.А., Ильин Е.Г., Копытин А.В. и др.//Пат.РФ. №2017146,МКИ G01N27/333.
Опубл.30.07.94.
Masse R., Grenier J.C. // Bull. Soc.Franc. Mineral.Cristallogr.1971.V94.,P.437.
Bierlein J.D.,Gier T.D.,E.I.Du Pont. //Pat. USA. №3949323.
Bierlein J.D., Arweiler C.B. //Appl. Phys.Lett. 1986. V.49, P.917.
Маслов В.А., Селяненко В.Н. и др. // Выращивание крупных кристаллов КТР раствор
– расплавным методом. Расшир. Тезисы доклада V11 Всесоюзной конф. по росту
кристаллов. 1988. Т.2. c.230.
IUPAC Recomendation for Nomenclature of IonSelective Electrodes // Pure. Appl. Chem.
1976. №48. P.127

10. Belt R.F., Gashurov G., Liu Y.S.. KTP as a harmonic generator for Nd:YAG lasers //Laser
Focus. 1985. V. 10. P.110-124.
11. Belt R.F., Iradi Т.. Hydrothermal growth produces large KTP nonlinear crystals//Technology Guide: Optical materials. 1993. V.11. P. 155-162.

ISTR 2011 International Advisory Committee (G.Kodina, K. German, T. Gerber)
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6.P6.

QUANTUM CHEMICAL STUDY OF SUBNANODIMENTIONAL MIXEDCLUSTERS OF TECHNETIUM AND RUTHENIUM
Yu.V.Plekhanov, K.E.German
Institute of Physical Chemistry and Electrochemistry, RAS
31, Leninskii pr., Moscow, Russia

Previous [1] quantum chemical DV-X [2] calculations based on the density functional theory
proved adequacy and reliability of cluster models for the metallic technetium electronic structure
analysis. We extended these models for mixed TcxRuy phase appearing due to transmutation ofradioactive Tc99 into stable Ru100 [3]. As a bulk phase our simple model clusters used the same
electronic density for volume and surface sites. Interatomic distances for mixed models were linear
interpolated by content between pure Tc and Ru metal ones as it’s shown in [4]. We took into
account all low concentration models of Tc or Ru, but in the middle concentration area we used
only statistically averaged data for rather small (~10) random sets of atom positions. Because it issimilar character of results for both fragments, only the most informative electronic structure
characteristics of 21-atomic model graphic data will be given further.The electronic configurationsof pure metallic models Tc 4d5.665s0.735p0.60 and Ru 4d6.675s0.715p0.60 for mixed models vary slightly.
It is about 10% for 5s5p-states and up to 3% for 4d-states. The most modification of 4d-Tc
population is 0.15е for 13-atomic model. 4d-Tc population is monotone weakly logarithmicallydecreasing while Ru part enlarges. At the same time for effective charges we found approximately
linear dependence from Ru content . For all atomic positions and some Ru concentration it was
occured electronic density displacement toward Ru and very similar tendencies.
Fermi level position in our models approximately corresponds to the high occupied cluster
orbital. Relative location of this level also linearly drop. Density of states (DOS) at Fermi level
dependence has a rather intricate shape. At the low concentration of some metal DOS is relatively
less then the same one for the pure metals or for the central part of the graphic. DOS absolute
maximum position corresponds to ~70% output of transmutation products. Commonly thisparameter has arising tendency during the transmutation process (dashed line). Finally, we
estimated models stability by sum of Mulliken bond overlap population indexes over all bonds per
one atom of model. It is excellent linear tendency for the bond weakening during transmutation. All
this facts also well corresponds with general qualitative theory [5]: new more electronegative atom
sublattice results to more strength bonding, correlates with the shift of occupied states in the lower
energy area; descends Fermi level from the middle to the end of transition metal row and decreases
density of states at Fermi level.
Therefore the same behaviour of electronic structure characteristics for both models arises theprobability of these conclusions for the real samples. We can sum up that transmutation causes
serious changes in electronic structure of initial metallic Tc, which influences on its chemical
activity, physical-chemical and mechanical properties.
Acknowledgments: The work was supported by RFBR grant 09-03-00017.
REFERENCES[1] Yu.V.Plekhanov, K.E.German, R.Sekine // Radiochemistry (Russ.), 45(2003) 217.
[2] H.Adachi, M.Tsukada, C.Satoko // J.Phys.Soc.Jpn. 45(1978) 875[3] V.F.Peretrukhin, S.I.Rovnyi, V.V.Ershov et al // Zh. Neorg. Khim.(Russ.), 47(2002), no. 5, 722.
[4] Y.Shirasu, K. Minato // J. Alloys Comp., 335(2002), nos.1-2, 224.
[5] R.Hoffmann Solids and Surfaces: A Chemist’s View of Bonding, VCH Publisher Inc., 1988.

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6.P7.
DEPOSITION OF TECHNETIUM COATINGS BY THERMOLYSIS
OF VOLATILE CARBONYL COMPOUNDS
G.V. Sidorenko, A.E. Miroslavov, and D.N. Suglobov
Khlopin Radium Institute, Research and Production Association, Federal State Unitary Enterprise,
2-i Murinskii pr. 28, St. Petersburg, 194021 Russia

Technetium carbonyl compounds [TcBr(CO)5], [TcI(CO)5], [TcX(CO)3]4 (X = Cl, Br, I), [TcBr(CO)3en](en = ethylenediamine), [Tc(RCOCHCOR')(CO)3(Et2NH)] [R = CH3 or C(CH3)3, R' = CF3], Tc2(CO)10 and[Tc(C5H5)(CO)3] were tested as precursors for chemical vapor deposition of technetium coatings on model
supports (external surface of titanium tubes) with the aim to evaluate the possibility of using technetium
coatings for biofouling protection of critical units of installations operating in seawater. The deposition
conditions and yields were determined. The necessary conditions for ensuring high deposition yield are
occurrence of the decomposition in one effective step and, in the case of carbonyl halides, presence of areductant, internal (ethylenediamine) or specially introduced into the gas phase.
The microstructure of the coatings obtained was examined by electron microscopy. The chemicalcomposition of the coatings (carbon content) was determined. The coatings were studied by X-ray diffraction
analysis, and phases of metallic technetium, solid solution of carbon in technetium, technetium carbide, andintermetallic compounds of technetium with titanium (support material) were revealed. Along with the wellknown hexagonal phase, a new phase of technetium metal, body-centered cubic with a = 0.325 nm, wasrevealed; it is usually formed in thin (less than 1 μm) films. The corrosion resistance of the films in simulatedseawater was studied by monitoring the accumulation of technetium in seawater contacting with the coatedspecimen. The correlation between the precursor composition, conditions of heat treatment of the coatings,
chemical and phase composition of the coatings, and their corrosion resistance is discussed. Hightemperature vacuum annealing (at no less than 900°С) is the necessary condition for preparing corrosionresistant coatings. The highest corrosion resistance is attained at low (<2%) and high (>15%) carbon content
in the coating. The best samples are not inferior in the corrosion resistance to dense technetium foil.
The most reliable results with respect to the whole set of parameters (deposition yield, adhesion of thecoating to the support, corrosion resistance) were obtained with the system [TcBr(CO) 3]4/ethylene glycol.
Ways to further improve the deposition process are outlined. The most important of them is more efficientpumping-off of gaseous reaction products.

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A. Malysheva and A.Maruk

Promissing to meet in Chicago (22th flor of Presidium RAS, Moscow)
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ROUND TABLE KEY LECTURE“FARMSINTEZ” CEO Timofei Petrov is giving axial lecture

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ISTR2011 Closing ceremony
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AUTHOR INDEX
Author Name

Page

Abdrahmanov, T.G.
285
Abdrahmanova, Z.T.
247
Abdulahatov, M.K.
176
Abdusalomov, A.A.
281
Abisheva, Z.S.
208, 235, 241, 247
Abkhalimov, E.V.
427
Agapova, L.Ya.
241, 247
Al-Hokbany, N.S.
356
Al-Jammaz, I.J.
356
Alberto, R.
301
Aleksandrova, O.P. 317, 332
Aliev, R.A.
150, 192
Allabergenov, R.D.
272
Altmaier, M
31
Alwaer, S.
151
Aminjonov,А.А. 65, 73, 86, 91,102, 400
Ananyev, A.V.
121
Andreev, V.N.
10
Antipkin, N.R.
416
Anyszkiewicz, K.
148
Areshina, N.S.
265
Artamonova, L.D.
355
Babain, V.А.
112
Balanovskyi, N.V.
277
Bańkowski, K.
343
Baranov, N.G
321, 327, 352
Bartenev, S.A.
176
Batuk, O.
193
Baulin, V.Е.
338
Beknazarova, N.S.
400
Belyanin, M.L.
310
Benke, G.
148
Bessonov, A.A.
438
Betenekov, N.D.
146
Biljalova, G.A.
416
Blokhin, А.А.
254, 265
Bogorodskaya, M.A.
416
Bogorodsky, A.O.
416
Boltoev, Yu.D.
168
Bonardi, M.L.
319
Borbat, V.F.
73
Borisova, L.V. 138, 144, 223, 262
Boytsova, Т.А.
112
Bozhkov, O.
223, 262
Braband, H.
301
Britvin, S.N.
135

Bruskin, A.B.
Brylev, К.А.
Bryskin, B.D.
Bulatov, G.S.
Burakov, B.E.
Burkhanov, G.S.
Burtsev, M.Yu.
Bychkov, A.V.
Bykov, A.N.
Bykov, G.L.

.

307
27, 58, 74
375
162, 436
190
407
297
10
373
169

Chagovets, N.S.
416
Chekmarev, A.M. 10, 277-288, 411
Chernyadeva, O.A.
277
Chernyshov, A.A.
409
Chernyshova, О.V. 29, 44
Chibisov, E.V.
351
Chikova, I.V.
310
Chiozzone, R.
53
Chistyakov, A.V.
44
Chmielarz, A.
148
Chotkowski, M.
137
Chukalina, M.V.
429
Ciulik, J.
379
Cupial, S.
148
Czerwiński, A.
70
Czerwinski, K.R. 10, 28, 55, 57, 99
Danylenko, M.I.
165
Denden, I.
96
Denisov, E.I.
337
Depmeier, W.
135
Didyk, A.Yu.
79
Dilworth, J.R.
11
Drobot, D.V. 10, 29, 44, 54, 59, 380,421
Dvoeglazov, K.N.
167
Essehli R.
96
Epstein, N.B.
355
Ermolaev, A.V.
74
Ershov, B.G
10, 169, 427, 428
Fattahi, M.
96
Fedorov, V.Е.
27, 58, 74
Fedosseev, A.M. 98, 438
Fellhauer, D.
31
Filyanin, А.Т.
320
Filyanin, O.A.
320
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7 International Symposium on Technetium and Rhenium – Science and Utilization - Moscow, 2011

Firsin, N.G.
Forester, P.M.
Frolov, K.N.
Fujii, Y.
Fuks, L.

176, 411
59
10
107
339

Gaona, X.
32
Garbuzov, V.M.
190
Gayfulin, I.M.
101
Gedgagov, E.I. 10, 217, 218
Gedgovd, K.N. 162, 436
Gerber, Th.
11, 30German, K.E. 10, 11, 15, 96, 100, 114, 121,
173-194, 297, 429, 435, 439-450
Gini, L.
319
Glukhov, G.G.
351
Gniazdowska, E.
339, 343
Goikhman, M.J.
88
Golovanov, D.
149
Golubev, M.N.
337
Goncharuk, T.Ju.
388
Gorina, N.B.
407
Gorshkov, N.I
311
Goryunov, Е.I.
175
Goryunova, I.B.
175
Grechnikov, A.A.
144
Gribanov, A.V.
176
Grigoriev, M.S.
10, 37, 38, 97, 98, 440
Gromov, P.B.
293
Groppi, F.
319
Gurzhij, V.V.
38, 39Gusel'nikov, V.S.
176
Guseva, E.V.
409
Habashi, F.
Hartmann, T.

104
57

Ilyin, E.G.
Irtegov, A.I.
Ishizaka, Sh.
Ismailov, N.P.
Ito, A.
Ivanov, I.A.

445
56
27
281
27
192

Johnstone, E.
Juraev, Sh.

29, 5985

Kabirov, N.G.
Kablov, E.N.
Kadirova, Z.Ch.
Kalantarova, P.E.
Kalinnikov, V.Т.

75, 88, 91
10, 1885
253
293

Kalmykov, S.N.
173, 192, 193
Kanygin, V.V.
332
Karpukhin, A.V.
439
Kasikov, A.G.
10, 232, 265, 268, 293
Katayev, E.A.
105
Kataeva, L.I.
10
Kazanskaya, N.K.
394
Kerlin, W.M.
57
Khijniak, T.V.
128, 188
Khomushku, G.M.
355
Khrustalev, V.N.
54, 105
Kilibayeva, S.K.
241
Kim, E.
59
Kirakosyan, G.A. 99, 105
Kitamura, N.
27
Klementyeva, О.Е. 347, 369
Klyopov, A.N.
317, 332
Kobayashi, T.
32
Kodina, G.E. 10, 300, 307, 320, 347, 369,
373
Kolesnikov, G.V.
105
Kolupaev, D.N.
10, 121
Konovalov, E.Е.
136, 168
Konovalov I.S.
197
Kopytin, A.V.
194, 445
Kormilitsyn, М.V.
10, 191
Korneyko, Yu.I.
135, 190
Korolev, V.А.
112
Korsunsky, V.N.
308
Kostylev, A.I.
411
Kovalenko, O.V.
338
Koyama, S.
107
Kozar', A.A.
113, 160
Kozitsyna, N.Yu.
183
Kozminski, P.
339, 343
Krajnikov, A.V.
387
Krasikov, V.D.
311
Kravchenko, N.G.
191
Kremer, C.
55
Krivovichev, S.V.
137
Krylov, V.V.
317
Kriyzhovets, О.S.
45, 61
Kudryavtsev, G.E.
10
Kulakova, I.I.
439
Kulikauskas, V.S.
81
Kurachenko, Y.A.
317
Kurykin, M.A.
56
Kuznetsov, A.A.
108, 158
Lebedev, V.A.
Leonhardt, T.
Leszczynska-Sejda, K.

10
379
148
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Levchuk, О.М.
Levin, А.М.
Lapshina, E.
Lumpov, А.А.
Lvovskiy, A.I.
Lyamina, O.I.
Lyubimov, D.Yu.

271
271
319
38, 426422
10162, 436

Mabatkadamova, K.S.
91
Majidzade, V.A.
253
Malakhova, I.I.
311
Maltseva, Е.Е.
254, 265
Malysheva, А.О.
347, 369, 373
Manenti, S.
319
Manuylov, R.N.
386
Maruk, A.Ya.
98, 100, 307, 440
Mashkin, А.N.
121, 174
Maslennikov, А.G.
191
Maslennikov, Yu.S.
351
Matusevich, Еu.S.
317
Mayboroda, A.B.
285
Mayer, P.
31
Mazilin, I.V.
380
Melentev, A.B.
121, 173, 174
Melnikov, S.А.
386
Merkulov, V.G.
351
Mescheryakov, N.M.
230
Mikhaylenko, M.A.
220, 254
Minin, V.V.
138
Minko, Yu.V.
327
Minn, A.
288
Mironov, Yu.V.
28, 60, 76, 101
Miroslavov, A.E.
10, 39, 38, 426
Misharin, V.А.
121
Morito, F.
387
Moisy, Ph.
11, 114, 438
Morozov, P.A.
428
Murashkin, Ju.V.
254
Murko, A.Yu.
314
Murzin, V.Yu.
11, 429, 440
Myasoedov, B.F.
10, 13, 175
Naumov, N.G.
Nazarov, E.O.
Nazarova, O.V.
Nekhoroshev, N.E.
Nenashev, S.N.
Nerozin, N.A.
Nesterov, E.A.
Nesterova, J.V.
Nifantiev, E.Е.
Nikishina, E.E.

60
19, 167311
220
391
330, 355
309, 310
309, 310
177
56

Nikolaev, A.I.
Nikonov, B.S.
Niyazmatov, A.A.
Novikov, J.N.
Novojilov, V.A.
Novruzova, F.S.

10
138
275
178
320
253

Obruchnikova, Ya.A. 114, 439, 440
Oleynikov, P.P.
388
Orlov, S.P.
320
Oshchepkov, V.N.
308
Ospanov, E.A.
217
Ospanov, N.A.
217
Ozawa, M.
11, 20, 107, 112
Palant, А.А.
Parpiev, N.A.
Parshin, A.P.
Peretrukhin, V.F.
.
Petriev, V.M.
Pet’kov, V.I.
Petrakova, О.V.
Petrova, А.М.
Petrov T.
Petrushin, N.V.
Pichuzhkina, Е.М.
Plekhanov, Yu.V.
Pleshkov, M.A.
Plevaka, A.V.
Pokhitonov, Yu.А.
Poineau, F.
99
Pokrovskiy, Yu.G.
Politov, Yu.A.
Ponomareva, E.I.
Popova, N.N.
Potapova, K.I.
Potgieter, K.
Povarova, K.B.
Pryamilova, E.N.

10, 27187386
10, 11, 113, 114, 160,
181, 187, 191
321, 332
77
45, 61, 422
232, 265, 268, 293
453
18
166
454
254
288
112
11, 15, 28, 55, 59, 96,
411
448
247
169, 297285
3110, 58, 394
30

Qeybatova, A.F.

253

Rabinovich, E.Z.
Radchenko, V.М.
Reshetnik Y.N.
Reshetova, O.V.
Roberov, I.G.
Rogov, A.S.
Romanovsky, V.N.
Rotmanov, K.V.

308
191
373
271
407
309, 310
320
113, 191
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Ryabukhin, V.A.

146

Sadkin, V.L.
309, 310
Sadykanova, S.E.
109
Safarmamadov, S.М. 75, 88, 91
Safiulina, A.М.
175, 297
Saito, M.
107
Sakuda, E.
26
Salahova, E.A.
253
Sapukov, I.A.
241
Sarychev, G.A.
10
Sattelberger, A. 11, 28, 55, 57, 99
Sayre, E.D.
375, 395
Sazanov, J.N.
176
Sazonov, A.B.
416
Schibli, R.
311
Scott, B. L.
28, 57
Sekine, T.
11
Semenova, A.A.
321, 327, 352
Sergeeva, L.N.
167
Sharipov, Kh.T.
85, 272
Sharipov, R.Kh.
85, 272
Sharygin, L.М.
337
Shevelkov, А.V.
44, 59
Shilov, V.P.
121
Shilyaev, A.V.
277, 288
Shinohara, A.
26
Shiryaev, A.A. 173, 429, 439, 440
Shiryaev, S.V.
308
Shiryaeva, V.K.
332
Shulepov, S.S.
168
Sidorenko, G.V. 37, 38, 426, 451
Sidorov, V.V.
18
Skuridin, V.S.
312, 313
Skvortsov, V.G.
332, 355
Smirnov, N.A.
285
Smirnova, K.A.
44, 422Smolentsev, A.I.
74, 101
Snigirev, Еu.V.
317
Solovov, R.D.
428
Stasiuk, E.S.
312
Stepchenkov, D.V. 321, 327, 352
Suglobov, D.N. 37, 38, 426, 451
Sukhanov, М.V.
75
Suharev, S.S.
155
Sulim, E.V.
321, 327, 352
Suo, Ch.
26
Suzuki, T.
107, 112

Tarasov, V.P.
99
Taratonenkova, N.
369
Tkachuk, D.A.
320
Tomilin, S.V.
166
Troshkina, I.D. 10, 11, 202, 277, 281, 285,
288, 298, 411
Tugarina, О.V.
174
Tsivadze, A.Yu. 10, 11, 181, 320, 338
Tsodikov, M.V.
44
Tumanova, D.N.
114, 181, 288
Tzvetkova, Ch.
223, 262
Usolkin, А.N.
Ulanovskiy, A.A.
Urusov, Yu.I.

338
388
194, 445

Varlamova, N.V.
Vazchenkov, M.V.
Veligzhanin, A.A.
Vidanov, V.L.
Voit, A.V.
Voldman, G.М.
Volk, V.I.
Volkov, V.P.
Voroshilov, Yu.А.

309
298
409
167
288
386
10, 167
230
338

Weck, Ph.

28, 57, 99

Yakovlev, N.G.
Yalfimov, A.N.
Yarovoy, S.S.
Yordanova, T.
Yoshimura, T.
Yudintsev, S.V.

338
426
27
55
26
136

Zagorodnyaya, A.N. 208, 235
Zakharova, E.V.
193
Zakharyan, S.V.
217
Zaytsev, P.A.
388
Zemskova, L.A.
288
Zhukov, A.F.
194
Zolotova, Yu.I.
311
Zubavichus, Ya.V.
173, 409, 429, 440
Zukau, V.V.
351
Zykov, M.P.
176, 320

Tananaev, I.G. 10, 105, 121, 169, 173, 174,
175, 192, 435
Tarasov, V.A.
113
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