Environmental Amorphous Materials Science Group:from basic research to SDGs* oriented-applications* SDGs: Sustainable Development Goals – UNESCO - 2015

◼ Nanba & Benino Group
Graduate School of Environmental & Life Science,

Faculty of Engineering,
Okayama University⚫ Topics in 2022
On May 18, 2021, the United Nations General Assembly
approved a resolution declaring the year 2022 as :The International Year of Glassto celebrate the heritage and importance of this material in our lives.
 https://www.iyog2022.org/

Glass and SDG global goals.

for deeper understanding of the relation between glass and the SDGs
 https://www.youtube.com/watch?v=eXpbt5U3OzA2

We are the glassmen!
◼ Let’s be glassmen, all of us.
Glass has long been widely used for windows and cups.
Glass properties are also commonly used to solve environmental issues.
We contribute to SDGs achievements by developing very efficient
functional glass and ceramic materials
Novel waste-recycling methods and glass-solidification methods ofradioactive wastes are investigated.

NANBA Tokuro
Professor
tokuro_n@okayama-u.ac.jp

BENINO Yasuhiko“俺達，硝子屋.
We, the glassmen.”

Associate Professor
benino@okayama-u.ac.jp

On going projects◼ Basic Science⚫ Relation between structure and properties of glass⚫ Glass structure analyses by experiments and computer simulations◆ Experiments: X-ray and Neutron diffraction, XPS, Raman/IR, NMR◆ Simulations: Molecular orbital (MO), Band calculation, Molecular dynamics (MD),
Reverse Monte Carlo (RMC)◆ Glasses: SnO-P2O5, Bi2O3-B2O3, PbO-B2O3, Mo-containing borosilicates and phosphates,
anisotropic meta-phosphates◼ Applied Science⚫ Pb-free glass: SnO-based phosphate glass for white phosphor⚫ Waste treatment and related subjects◆ Chemical recycling process:
Recovery of Si, P, and Ti from municipal waste slag, steel making slag, and sewage sludge ash◆ Removal process: Radioactive Cs and heavy metals of Pb, Cd, Cr from soils◆ Glasses for solidification of nuclear wastes: PbO-ZnO-B2O3 glass for Iodine-129 immobilization

 Our focused projects: ⚫,◆3

4

Focused projects◼ Novel waste treatment processes⚫ Recovery of valuable elements from wastes: Si, P, Ti⚫ Removal of radioactive and hazardous elements in soils: Cs, Pb, Cd, Cr
Raw material of glasses: SiElution of coloring
elements: Fe, etc.

Promoters for
vitrification& volatilization③Municipal waste slag

www.bam.deBase treatment①②Melting at hightemperatures

Acidtreatment

Sewage sludge ash

Glass

Colorless glass: Si, P, Ti

Fly ash: Cs, Pb, Cd, Cr

www.47news.jp/

Al Kα

Si Kα

P Kα

Ca Kα

Ti Kα

Fe Kα

100

Cs volatility (%)

Contaminated soil

Volatilization
as chlorides

Separationof P from Ti

80
6040
20

CaCl₂NaClMgCl₂01000 1100 1200 1300 1400
Melting temperature (℃)

Volatility of Cs in a soil vs melting temperature
at different chlorination promoters  Nakao et al. (2018)

SiO2 particles

P2O5-TiO2 particles

TEM photos of a colorless glass after acid treatment,suggesting different precipitation process of SiO2 andP-containing TiO2 particles.  Omura et al. (2013)

5Focused projects◼ Glasses for nuclear waste solidification⚫ PbO-ZnO-B2O3 glass for Iodine-129 immobilization (Half-life of 129I: 15.7 million years)⚫ Structure analysis and chemical stability prediction of glasses by computer simulations◆ Structure modeling of 2PbO-B2O3 glass by RMC simulation
Previously reported structure: PbO3 trigonal pyramid (tp) and PbO4 trigonal bi-pyramid (tbp)
Difficulty in modeling: Reproduction of asymmetric structures, such as tp and tbp
Limitation of the conventional RMC method:(a)(b)

rOCG

tp

Poor reproducibility ofPbOn units around 2.6 ÅtbpOne of the ligands islone pair of electrons.

Eccentric distance | r | between the center of gravity of oxygen atoms, OCG and (a) B or (b) Pb  Nagao et al. (2022)

Challenge: New RMC calculation option based on AI evaluation of configuration energy

Selected publications◼ Development of novel waste treatment processes⚫ T. Nanba, S. Mikami, T. Imaoka, S. Sakida, Y. Miura, Chemical recycling of inorganic wastes by using phase separation ofglass, J. Ceram. Soc. Japan, 116(2) (2008) 220-223, doi:10.2109/jcersj2.116.220⚫ T. Nanba, Y. Kuroda, S. Sakida, Y. Benino, Chemical recycling of municipal waste slag by using phase separation, J. Ceram.
Soc. Japan, 117(11), (2009) 1195-1198, doi:10.2109/jcersj2.117.1195⚫ Y. Benino, Y. Ohtsuki, S. Sakida, T. Nanba, Effect of additives on the distribution of phosphorus associated with phaseseparation of borosilicate glasses, J. Ceram. Soc. Japan, 120 (11), (2012) 490-493, doi:10.2109/jcersj2.120.490⚫ K. Omura, S. Sakida, Y. Benino, T. Nanba, Distribution behavior of inorganic constituents in chemical recycling processes of amunicipal waste slag, J. Asian Ceram. Soc., 1 (2013) 108-113, doi:10.1016/j.jascer.2013.03.003◼ Development of glasses for nuclear wastes solidification⚫ A. Mukunoki, T. Chiba, Y. Suzuki, K. Yamaguchi, T. Sakuragi, T. Nanba, Further Development of Iodine Immobilization
Technique by Low Temperature Vitrification With BiPbO2I, ASME 2009 12th International Conference on Environmental
Remediation and Radioactive Waste Management, ICEM2009-16268, 329-334, doi:10.1115/ICEM2009-16268⚫ A. Mukunoki, T. Chiba, Y. Benino, T. Sakuragi, Microscopic structural analysis of lead borate-based glass, Progress in Nuclear
Energy, 91, (2016) 339–344, doi:10.1016/j.pnucene.2016.05.008⚫ M. Nagao, S. Sakida, Y. Benino, T. Nanba, A. Mukunoki, T. Chiba, T. Kikuchi, T. Sakuragi, H. Owada, Effect of bond valence
sum on the structural modeling of lead borate glass, J. Non-Cryst. Solids, (2022) in press,
doi:10.1016/j.jnoncrysol.2022.121751◼ IYOG2022⚫ T. Nanba, Y. Benino, T. Akai, Environmental activities on glass in Japan, J. Ceram. Soc. Japan, (2022) in press.

67International students from Europe◼ Internship program⚫ 2017: -1 -Pierre and Marie Curie University⚫ 2018: - 1 – UPMC - Paris,- 2 - University of Poitiers⚫ 2019: - 1 -Sorbonne University,- 2 -University of Poitiers⚫ 2022: - 1 – INP Toulouse,- 2 – INP - Grenoble,- 3 - University of Turin2019

201720182022

International students from Europe

Trip to Kyoto, 20178

9International students from EuropeOsaka, 2019 https://www.facebook.com/okadaiceramics

Trip to Onsen, 2018