Progress in Am transmutation targets fromEFTTRA
D. Haas, A. Fernandez (JRC-ITU)
D. Warin, J.-M. Bonnerot (CEA)
C. Garzenne (EDF)
W. Maschek (FZK)
F. Scaffidi-Argentina (JRC-IE)
F. Klaassen, R. Schram (NRG)
NEA P&T Exchange Meeting, Nimes, September 2006

The EFTTRA Collaboration: 15 years from 1992 to 2006
• Goal: transmutation of long-lived FP and MA• Tc-99 and I- 129 irradiations performed and reported• Inert matrices selection and irradiations in Phenix and HFR• Pre-selection of MgAl2O3 for Am targets transmutation• Irradiations (Am) in HFR: T4 and T4bis (2 burn-up levels)• Results not conclusive > Selection of Zirconia (once-through scenario)or MgO, Mo (multiple recycling scenario)• Preparation of HELIOS irradiation in HFR• Further developments
NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA: a 15-years successful collaboration• Agreement on experimental programmes, seminars, publications• Financing by the partners (case by case)• Financial (partial) support through EC Framework Programmes:• FP5 (EFTTRA T4)• FP6 (EUROTRANS IP: HELIOS, BODEX)NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA T4 and T4bis Objective• MgAl2O3 spinel as IMF for once-through transmutation• Development of Am spinel target fabrication• First irradiation testing of Am spinel• In-pile behaviour, transmutation demonstration• Burn-up effect (two irradiation times)

NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA T4 and T4bis main conclusions• Am spinel fabrication demonstrated, but improvements implemented(matrix powder infiltration instead of green pellet infiltration)• Irradiation successful (up to 650 days): no failure, good pellet structure• Very high gas production (mainly He), low release (low T°)• Very large pellet swelling (gas bubbles)• Am-Spinel chemical instability: formation of AmAlO3

NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA-T4(bis) pellets: green pellet infiltration
HELIOS: sol-gel beads infiltration
Inhomogeneous Am distribution in spinel

Solid-solution formation in the sintered pellet

MA-Laboratory

NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA T4 and T4bis main conclusions• Am spinel fabrication demonstrated, but improvements implemented(matrix powder infiltration instead of green pellet infiltration)• Irradiation successful (up to 650 days): no failure, good pellet structure• Very high gas production (mainly He), low release (low T°)• Very large pellet swelling (gas bubbles)• Swelling also due to n-damage• Am-Spinel chemical instability: formation of AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006

Power density in the EFTTRA T4bis irradiationT4 Irradiation time
400

350

Power Density [W/cm3]

300

250

200
242

150

83%

Cm

α -d e c a y90%
241

100

Am
10%

50

238

239

Pu

242

Am242m

17%

Am
242

Pu

Pu

00

100

200

300

400

500

600

700

Irradiation Time [full power days]

The two maxima are due to formation and fission of Am-242m and Pu-239, respectively. TheEFTTRA T4 irradiation showed a similar power profile, but it did not reach the second
maximum due to the shorter irradiation time.
NEA P&T Exchange Meeting, Nimes, September 2006

As-fabricated T4 fuelIrradiated T4: 17% porositya) BOLb) EOLAmAlO350 µm50 µm

Irradiated T4bis: 25% porosity

NEA P&T Exchange Meeting, Nimes, September 2006

T4bis Electron Probe Micro-Analysis
Composition of the 50% actinides remaining in the fuel0.7
Scan 0003-6-15

0.6

Uranium

Measured intensity (cnts/s)

Neptunium

Pu: 71 %Plutonium

0.5

Americium
Curium

0.4

0.3

0.2

Cm: 19 %Am: 10 %

0.1

0325

330

335

340

345

350
Wavelength (pm)

NEA P&T Exchange Meeting, Nimes, September 2006

355

360

365

370

375

EFTTRA T4bis Profilometry and X-ray image
Cross section for investigation

Outer cladding diameter (mm)

6.85

6.8

6.75

6.76.656.6455565758595

Axial position (mm)
NEA P&T Exchange Meeting, Nimes, September 2006

105115125a)

5 mm ≅ 1 μm

5 mm ≅ 320 μmb)
5 mm ≅ 2,5 μm

5 mm ≅ 320 μm

Profilometry and optical micrograph of an MgAl2O4 single crystal <110>orientated irradiated with iodine ions of 72 MeV energy. The respective fluences
are 1015 for a) and 1017 ions/cm2 for b). The optical micrograph shows clearly
the irradiated area poping out from the original crystal surface.
NEA P&T Exchange Meeting, Nimes, September 2006

EFTTRA T4 and T4bis main conclusions• Am spinel fabrication demonstrated, but improvements implemented(matrix powder infiltration instead of green pellet infiltration)• Irradiation successful (up to 600 days): no failure, good pellet structure• Very high gas production (mainly He), low release (low T°)• Very large pellet swelling (gas bubbles)• Swelling also due to n-damage• Am-Spinel chemical instability: formation of AmAlO3
NEA P&T Exchange Meeting, Nimes, September 2006

X-ray diffraction of EFTTRA-T4 fuel

EFTTRA-T4 1996

spinel +Am phase similar

cpsto AmAlO3

EFTTRA-T4 2006

spinel (crystalline!)no Am phase
AmAlO3 (Keller 1965)
20

30

40

5060

2θ (°) Cu Kα

NEA P&T Exchange Meeting, Nimes, September 2006

708090100

EXAFS measurement- annealing at 1600°C in Ar/H2(as for production in 1996)- about 60 mg Am-spinel powder in asteel shielded Plexiglass cuvette- measurement at INE Beamline at theÅngströmquelle Karlsruhe, ANKA

- interatomic distanceÆ EXAFS provides informationof local atomic structure:- coordination number- type of atom in coordination shells- disorder

NEA P&T Exchange Meeting, Nimes, September 2006

Am LIII-edge EXAFS of aged and annealed EFTTRA-T4
Data
Fit amorphous AmAlO3
Fit crystalline AmAlO3

1.0

2.36; 2.58; 2.88 Å

O1a-c

0.5

10 years aged EFTTRA-T4 fuelshows no peaks corresponding to aperiodic structure

Al N~13.28 ÅAl

3.25 ÅAm L3-edge EXAFS of annealed EFTTRA-T4

Am13.75 Åfuel can be fitted with AmAlO3 structure

0.0FT

1.0Am20.5

5.30 ÅAm36.50 ÅÆAmAlO3 is predominant
in EFTTRA-T4 fuel0.002468R+Δ (Å)
NEA P&T Exchange Meeting, Nimes, September 2006

General conclusion related to the use of spinel as IMF• Conclusion based on T4+T4bis + other experiments in HFR and Phenix• At low temperature, He retention leading to swelling• At high temperature He release, but chemical instability• Study started of a more stable IMF (once-through): Y-stabilised Zirconia• Additional investigation of MgO and Mo for recycle strategies• Need of irradiation experiments: HELIOS in HFRNEA P&T Exchange Meeting, Nimes, September 2006

EUROTRANS IP (FP6) Irradiation Tests¾ FUTURIX: irradiation test in Phénix of TRU-fuels
under EFIT relevant conditions¾ BODEX: irradiation test in HFR to study the heliumbuildup and release from inert matrixes for IMF’s¾ HELIOS: irradiation test in HFR to study the in-pile
behaviour vs temperature of U-free Am targets
NEA P&T Exchange Meeting, Nimes, September 2006

HFR-Petten

A B C D E F G H
1+ + + ++2+3+4+5+6+7+8+9 + + + + + + + + +NEA P&T Exchange Meeting, Nimes, September 2006

+ + + +HELIOSFuelControl rod+ Be reflector
Irradiation
positionsHELIOS test matrix
Pin Nr

12Composition

Am2Zr2O7+MgO(Am,Zr,Y)O2

Microstructure

10-50 μm

As-fabricateddensity [g/cm3]
241Am

Putot

0.7

0Solidsolution

0.7

Solidsolution

0.7

0.39

4(Zr,Am,Y)O2+Mo60-120 μmmax 30 vol%0.7040-150 μm
max 30 vol%0.3

NEA P&T Exchange Meeting, Nimes, September 2006

CEACerCer

1.2

Instrumented
withCentral TC

JRC-ITU

JRC-ITU

JRC-ITU

Remarks

Instrumented
withCentral TC

JRC-ITU(Am,Pu,Zr,Y)O2(Pu,Am)O2+Mo

Fuel
Type

03

5

Fuel
Manufacturer

Cer
MetCerMetPower calculations
250

Fission power (W/cm)

200

Pufis 0.08 g/cm3 + 241Am 0.7g/cm3150100

24150

Am 0.7 g/cm3

Fission of 239Pu

Fission of 242mAm

Pufis 0.08 g/cm300100

200

300400

NEA P&T Exchange Meeting, Nimes, September 2006Irradiation Time (Days)

500

600

Estimated temperatures
PinLinearPower

TcentralCalculatedwith power

Pu-content

Am-content

Max
Power

[g/cm3][g/cm3][W/cm3][W/cm][oC][W/cm3]Composition

1

Am2Zr2O7 + MgO

00.7

240

56741

300

2(Am,Zr,Y)O200.7

170

40

811

230

3(Pu,Am,Zr,Y)O20.39

0.7

740

170

1439

787

4(Am,Zr,Y)O2 + Mo

00.7

250

58

687

300

5(Pu,Am)O2 + Mo

1.20.3

1600

370

1477

2020

¾ Onset of He release: ≈ about 550 oC¾ Complete He release: ≈ about 1350 oC
NEA P&T Exchange Meeting, Nimes, September 2006

(Am,Zr,Y)O2 pre-fabrication tests

Sintered density > 90%TD

NEA P&T Exchange Meeting, Nimes, September 2006

HELIOS Status• HELIOS irradiation shall start in 2007 in the HFR and last for
about 1 year (i.e. 10 HFR cycles)• Fuel production and hardware procurement & manufacturing
underway• Predicted temperatures in the fuels are acceptable (slightly lower
than aimed)• Destructive PIE’s results shall be available in 2009

NEA P&T Exchange Meeting, Nimes, September 2006

Future EFTTRA plans• Complete HELIOS experiment within EUROTRANS IP• Integrate the results within other experiments: BODEX• Demonstrate the high Am transmutation capability of Zirconia IMF
with a 5-years irradiation in HFR: HELIOSbis (not decided – funding
dependent• Looking at the feasibility of Cm transmutation in once-through mode

NEA P&T Exchange Meeting, Nimes, September 2006