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Fundamental and Technological Aspects of Actinide Oxide Pyrochlores: Relevance For Immobilization Matrices

Published online by Cambridge University Press:  10 February 2011

P. E. Raison ,
R. G. Haire ,
T. Sato  and
T. Ogawa
P. E. Raison
Affiliation:
Oak Ridge National Laboratory, P. 0. Box 2008, Oak Ridge, TN 37831-6375 USA
R. G. Haire
Affiliation:
Oak Ridge National Laboratory, P. 0. Box 2008, Oak Ridge, TN 37831-6375 USA
T. Sato
Affiliation:
Japan Atomic Energy Research Institute, Tokai-mura, 319-11, Japan
T. Ogawa
Affiliation:
Japan Atomic Energy Research Institute, Tokai-mura, 319-11, Japan
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Abstract

Polycrystalline pyrochlore oxides consisting of selected f elements (lanthanides and actinides) and Zr and Hf have been prepared and characterized. Characterization to date has been primarily by X-ray diffraction, both at room and at elevated temperatures. Initial studies concentrated on selected lanthanides and the Np, Pu and Am analogs (reported here) but have been extended to the other actinide elements through Cf. Data from these studies have been used to establish a systematic correlation regarding the fundamental materials science of these particular pyrochlores and structurally related fluorite-type dioxides. In addition to pursuing their materials science, we have addressed some potential technological applications for these materials. Some of the latter concern: (1) immobilization matrices; (2) materials for transmutation concepts; and (3) special nuclear fuel forms that can minimize the generation of nuclear wastes. For f elements that display both a III and IV oxidation state in oxide matrices, the synthetic path required for producing the desired pyrochlore oxide is dictated by their pseudo-oxidation potential the stability of the compound towards oxygen uptake. For the f elements that display an oxidationreduction cycle for pyrochlore-dioxide solid solution, X-ray diffraction can be used to identify the composition in the oxidation-reduction cycle, the oxygen stoichiometry and/or the composition. This paper concentrates on the Np, Pu and Am systems, and addresses the above aspects, the role of the crystal matrix in controlling the ceramic products as well as discussingsome custom-tailored materials.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 556: Symposium QQ – Scientific Basis for Nuclear Waste Management XXII , 1999 , 3
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1. Ringwood, A. E., Kesson, S. E., Reeve, K. D., Levins, D. M. and Ramm, E. J. in Radioactive Waste Forms for the Future, eds. Lutze, W. and Ewing, R. C., Elsevier, Amsterdam, 1988, pp.233–334.Google Scholar
2. Ringwood, A. E., Kesson, S. E., Ware, N. G., Hibberson, W. and Major, A., Nature 278,219(1979).Google Scholar
3. Vance, E. R., MRS Bulletin XIX, No.12, Dec., 1994, 28–32.Google Scholar
4. Harker, A. B., in Radioactive Waste Forms for the Future, eds. Lutze, W. and Ewing, R. C., Elsevier, Amsterdam, 1988, pp.335–392.Google Scholar
5. Lutze, W. and Ewing, R. C., in Radioactive Waste Forms for the Future, eds. Lutze, W. and Ewing, R. C., Elsevier, Amsterdam, 1988, pp.699–740.Google Scholar
6. Shoup, S. S., Bamberger, C. E. and Haire, R. G., J. Am. Ceram. Soc. 79«6»,1489 (1996).Google Scholar
7. Longo, J. M., Raccah, P. M., Goodenough, J. B., Mat. Res. Bull. 5, 191(1969).Google Scholar
8. Subramanian, M. A., Aravamudan, G. and Rao, G. V. Subba, Prog. Solid State Chem. 15, 55(1983).Google Scholar
9. Kamizono, H., Hayakawa, I. and Muraoka, S., J. Am. Ceram. Soc., 74, 863(1991).Google Scholar
10. Hayakawa, H., and Kamizono, H., J. Nucl. Mat. 202, 163(1993).Google Scholar
11. Hayakawa, I. and Kamizono, H., J. Mat. Science 28, 513(1993).Google Scholar
12. Hayakawa, I. and Kamizono, H., Mat. Res. Soc. Symposium Proc. 302, 257(1992).Google Scholar
13. Chick, L. A. and Turcotte, R. P., Batelle Pacific Northwest Lab., Richland WA, Rept. PNL-4576, 1983.Google Scholar
14. Hart, K. P., Vance, E. R., Stewart, M. W. A., Weir, J., Carter, M. L., Hambleyt, M., Brownscomb, A., Day, R. A., Leung, S., Ball, C. J., Ebbinghaus, B., Gray, L. and Kan, T., Mat. Res. Soc. Symp. Proc., 506, 161(1998).Google Scholar
15. Chakoumakos, C. B. and Ewing, R. C., Mat. Res. Soc. Symp. 44, 641(1985).Google Scholar
16. Gong, W. L., Lutze, W. and Ewing, R. C., Mat. Res. Soc., Fall Symp., 1998 (in press).Google Scholar
17. Williams, D., Ames Lab., Ames, IA, Rep. IS-1052, 1962 (modified for PC use).Google Scholar
18. Smith, D. and Smith, K., Micro-Powd, Materials Data, Inc., Livennmore, CA, 1992.Google Scholar
19. Haire, R. G. and Eyring, L., in Handbook on the Physics and Chemistry of Rare Earth, Vol. 18, Lanthanides and Actinides: Chemistry, eds. Gschneidner, K. A. Jr., Eyring, L., Choppin, G. R. and Lander, G. H., North-Holland, Amsterdam, pp. 449–505, 1994.Google Scholar
20. Radzewitz, H., in Kernforshungzentrum Rep. N. 433, 1966, Karlsrhule, Germany.Google Scholar
21. Carroll, D. F., J. Am. Cerm. Soc., 46, 194(1963).Google Scholar
22. Oversby, V. M., McPheeters, C. C., Delguerdre, C., Paratte, J. M., J. Nuclear Mat., 245, 17(1997).Google Scholar
23. Aleshin, E. and Roy, R., J. Am. Chem. Soc., 45, 18 (1962).Google Scholar
24. Longo, J. M., Raccah, P. M. and Goodenough, J. B., Mat. Res. Bull, 191, 4 (1969).Google Scholar
25. Knop, O., Brisse, F., Castelliz, L. and Sutarno, A., Can. J. Chem., 43, 2812 (1965).Google Scholar
26. Pannetier, J. and Lucas, J., Mat. Res. Bull., 5, 797(1970).Google Scholar
27. Shannon, R. D., Acta. Cryst. A32, 751(1976).Google Scholar