Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T11:36:38.816Z Has data issue: false hasContentIssue false

Ruthenium Thermodynamics in Nuclear Waste Glasses

Published online by Cambridge University Press:  19 March 2012

S. Gossé
Affiliation:
CEA, DEN, DPC, SCCME, LM2T Commissariat à l’Energie Atomique et aux Energies Alternatives – Centre de Saclay 91191 Gif-sur-Yvette Cedex, France
S. Schuller
Affiliation:
CEA, DEN, DTCD, SECM, LDMC Commissariat à l’Energie Atomique et aux Energies Alternatives – Centre de Marcoule 30207 Bagnols sur Cèze Cedex, France
C. Guéneau
Affiliation:
CEA, DEN, DPC, SCCME, LM2T Commissariat à l’Energie Atomique et aux Energies Alternatives – Centre de Saclay 91191 Gif-sur-Yvette Cedex, France
H. Boucetta
Affiliation:
CEA, DEN, DTCD, SECM, LDMC Commissariat à l’Energie Atomique et aux Energies Alternatives – Centre de Marcoule 30207 Bagnols sur Cèze Cedex, France
Get access

Abstract

In high level radioactive glasses, the low solubility platinoids (Pd, Ru, Rh) precipitate to form (Pd-Rh-Te, Ru-Rh, Ru) metallic particles and (RuO2, Rh2O3) oxides during the vitrification process. The composition and microstructures of these phases can significantly modify the physico-chemical properties and the electrical or thermal conductivities during melting.

Several studies are undertaken at CEA in order to point out the reactions and the chemical interactions in the liquid and viscous states between the glass matrix and the platinoids present in the calcinated waste. Among these studies, a thermodynamic fission products database is being developed on the metallic (Pd-Rh-Ru-Te) and oxide (O-Pd-Rh-Ru-Te) systems. In this work, based on the Calphad method, the Gibbs free energies of each phase are modelled to provide an overall thermodynamic description of the platinoid phases in nuclear waste glasses. The objective of the database is to facilitate calculations of phase diagrams and thermodynamic properties. This flexible tool also enables calculations of the relative stability between metallic and oxide phases in function of the oxygen potential (RedOx equilibrium).

For example, some solidification routes are calculated for typical Pd-Rh-Ru-Te compositions of LWR spent fuels. The calculated Pd-Rh-Ru-Te solidification paths are compared with the phases analysed in simplified laboratory scale glass samples. Using these results, the compositions of the Pd-Rh-Ru-Te inclusions are predicted. Furthermore, possible consideration of the RedOx equilibria for some ruthenium based phases makes it possible to explain the speciation between oxide and metallic phases partly due to the Pd-Te interaction.

Type
Articles
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Mitamura, H., Murakami, T., Banba, T., Kiriyama, Y., Kamizono, H., Kumata, M., Tashiro, S., Nuclear and Chemical Waste Management 4 (1983)Google Scholar
2. Belyaev, A. V., Journal of Structural Chemistry 44, 1 (2003)Google Scholar
3. Krause, Ch., Luckscheiter, B., Journal of Materials Research 6, 12 (1991)Google Scholar
4. Galoisy, L., Calas, G., Morin, G., Pugnet, S., Fillet, C., J. Mater Research 13, 5 (1998)Google Scholar
5. Pflieger, R., Lefebvre, L., Malki, M., Allix, M., Grandjean, A., J. Nuclear Mater. 389, 3 (2009)Google Scholar
6. Pinet, O., Mure, S., Journal of Non-Crystalline Solids 355, pp. 221227 2009 Google Scholar
7. Jansson, B., Ph D thesis, Royal Inst. Techn., Stockholm, Sweden: KTM (1984)Google Scholar
8. Sundman, B., Jansson, B., Andersson, J-O., Calphad 9 (1985)Google Scholar
9. Gossé, S., Guéneau, C., Intermetallics 19, 5 (2011)Google Scholar
10. Gossé, S., Schuller, S., Guéneau, C., MRS Symposium Proceedings 1265 (2010)Google Scholar
11. Gürler, R., Journal of Nuclear Materials 199 (1992)Google Scholar
12. Raevskaya, M. V., Vasekin, V. V., Sokolova, I. G., J. of the Less Com. Met. 99 (1984)Google Scholar
13. Paschoal, J. O. A., Kleykamp, H., Thümmler, F., Zeitschrift Für Metallkunde 74, 10 (1983)Google Scholar
14. Hartmann, T., Ph D thesis, Forschungszentrum Karlsruhe GmbH., Germany (1996)Google Scholar
15. Dinsdale, A. T., Calphad 15, 4 (1991)Google Scholar
16. Kaye, M.H., Lewis, B.J., Thompson, W.T., J. Nuclear Mater. 366 (2007)Google Scholar
17. Lukas, H., Fries, S. G., Sundman, B., Computational Thermodynamics: The Calphad Method, 1 st edition, Cambridge University Press New York, NY (2007)Google Scholar
18. Kleykamp, H., Paschoal, J.O., Pejsa, R., Thümmler, F., J. Nuclear Mater. 130 (1985)Google Scholar
19. Kleykamp, H., J. Nuclear Mater. 171 (1990)Google Scholar
20. Bernath, S., Kleykamp, H., Smykatz-Kloss, W., J. Nucl. Mater. 209 (1994)Google Scholar
21. Okamoto, H, Journal of Phase Equilibria 12 (1991)Google Scholar