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Phase Relations of the Uranyl Oxide Hydrates and their Relevance to the Disposal of Spent Fuel

Published online by Cambridge University Press:  28 February 2011

R. J. Finch  and
R. C. Ewing
R. J. Finch
Affiliation:
University of New Mexico, Albuquerque, New Mexico, 87131
R. C. Ewing
Affiliation:
University of New Mexico, Albuquerque, New Mexico, 87131
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Abstract

Uranyl oxide hydrates, formed by the alteration of uraninite, are natural analogues for the long-term corrosion products of spent fuel in a geologic repository under oxidizing conditions. The uranyl oxide hydrates may be represented by the general formula:

Pb-bearing hydrates require the addition of a neutral uranyl group into the structural sheet (UO2(OH)2) for each interlayer Pb ion. Distortion of the structure associated with the additional uranyl groups is reduced by replacing two structural hydroxyls with a structural oxygen and a molecular water. The general formula for the Pb-uranyl oxide hydrates is:

This hypothesis explains the paragenetic sequences:

1) schoepite ➛ billietite ➛ protasite ➛ bauranoite

2) schoepite ➛ vandendriesscheite ➛ fourmarierite ➛ masuyite ➛ wölsendorfite

3) schoepite ➛ vandendriesscheite ➛ fourmarierite ➛ ± masuyite ➛ sayrite ➛ curite, and indicates that, under relatively high pH conditions, schoepite will not be the long-term solubility-controlling phase for uranium in uranium-rich groundwaters.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 212: Symposium P – Scientific Basis for Nuclear Waste Management XIV , 1990 , 241
Copyright
Copyright © Materials Research Society 1991

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References

REFERENCES

[1] Sverjensky, D. A., in: Alligator Rivers Analogue Project. Progress report for geochemical investigations of uranium mobility in the Koongarra ore deposit – a natural analogue for the migration of radionuclides from a nuclear waste repository. August 31, 1989. p. 313.Google Scholar
[2] Vochten, R. and Deliens, M., Phys. Chem. Minerals, 6, 129 (1980).Google Scholar
[3] Vochten, R., Huybrechts, W., Remaut, G. and Deliens, M., Phys. Chem. Minerals, 4, 281 (1979).CrossRefGoogle Scholar
[4] Loopstra, O., Acta Crystallogr. (1964), 17, 651.Google Scholar
[5] Vochten, R., in: Abstracts, vol. 1, The 15th General Meeting of the IMA, 28 June to 3 July, 1990, Beijing, China.Google Scholar
[6] Sobry, R., Am. Min., 56, 1065 (1971)Google Scholar
[7] Noe-Spirlet, M. R. and Sobry, R., Bull. Soc. Royal Sci. Liège, 43, 164 (1974).Google Scholar
[8] Finch, R. J. and Ewing, R. C., Radiochim. Acta, (in press)Google Scholar
[9] Pagoaga, M. K., Ph.D. Thesis, University of Maryland (1983).Google Scholar
[10] Piret-Meunier, J. and Piret, P., Bull. Minèeral., 105, 606 (1982).Google Scholar
[11] Pagoaga, M. K., Appleman, D. E. and Stuart, J. M., Am. Min., 72, 1230 (1987).Google Scholar
[12] Pagoaga, M. K., Appleman, D. E. and Stuart, J. M., Min. Mag., 50, 125 (1986).CrossRefGoogle Scholar
[13] Piret, P., Bull. Minèral., 108, 659 (1985).Google Scholar
[14] Piret, P., Deliens, M., Piret-Meunier, J., and Germain, G., Bull. Minèral., 106, 299 (1983).Google Scholar
[15] Mereiter, K., Tschermaks Min. Petr. Mitt., 26, 279–292 (1979).Google Scholar
[16] Taylor, J. C., Stuart, W. I. and Mumme, I. A., J. inorg. nucl. Chem., 43, 2419 (1981).Google Scholar
[17] Wilson, C. N., in: Scientific Basis for Nuclear Waste Management XII edited by Lutze, W. and Ewing, R. C. (MRS, Pittsburgh, 1989), pp. 473–483.Google Scholar
[18] Wilson, C. N., and Shaw, H. F., in: Scientific Basis for Nuclear Waste Management X edited by Bates, J. K. and Seefelt, W. S. (MRS, Pittsburgh, 1987) p. 123.Google Scholar
[19] Bates, J. K., Tani, B. S., Veleckis, E. and Wronkiewicz, D. J., in: Scientific Basis for Nuclear Waste Management XII edited by Oversby, V. M. and Brown, P. W. (MRS, Pittsburgh, 1990), pp. 499–506.Google Scholar