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Crystal Chemistry and Microstructures of Uranyl Phosphates

Published online by Cambridge University Press:  10 February 2011

Y. Suzuki
Affiliation:
Mineralogical Inst., Univ. of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan
T. Murakami
Affiliation:
Mineralogical Inst., Univ. of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan
T. Kogure
Affiliation:
Mineralogical Inst., Univ. of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan
H. Isobe
Affiliation:
Environmental Geochemistry Lab., JAERI, Tokai, Ibaraki 319-11, Japan
T. Sato
Affiliation:
Environmental Geochemistry Lab., JAERI, Tokai, Ibaraki 319-11, Japan
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Abstract

The crystal chemistry and microstructures of saleeite (Mg(UO2PO4)2•10H2O) and metatorbernite (Cu(UO2PO4)2•8H2O), from Koongarra, Australia and Shinkolobwe, Congo, were examined by X-ray diffraction analysis, infrared spectroscopy (IR), scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis, transmission electron microscopy (TEM) and analytical electron microscopy. The uranyl phosphates consist of uranyl phosphate layers with cations and waters in the interlayers. The IR spectra of saleeite and metatorbernite show the presence of hydroxyls in the interlayers in addition to water molecules. The d002 spacings of the hydrated phases of saleeite and metatorbernite up to 300°C reveal that the uranyl phosphate layers themselves are quite stable in the temperature range although the interlayer water molecules are lost easily. The presence of a mixed phase of saleeite and metatorbernite is confirmed in the micrometer and nanometer scales. However, SEM and TEM examination suggest saleeite and metatorbemite generally grow separately, and rarely form solid solution or interstratification. The results imply that U is retained in uranyl phosphate minerals even when the temperature at around repositories increases, and that saleeite and metatorbernite precipitate independently from solution according to their solubilities even when Mg2+ and Cu2+ coexist in solution.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

[1] Tripathi, V.S, Ph.D. dissertation, Stanford University, Palo Alto, California, 2 1p(1983).Google Scholar
[2] Hsi, C.-K. D., and Langmuir, D., Geochimica et Cosmochimica Acta, 49, 19311941(1983).Google Scholar
[3] Bruno, J., Pablo, J. D., Duro, L. and Figuerola, E., Geochimica et Cosmochimica Acta, 59, 41134123(1995).Google Scholar
[4] Langmuir, D., Geochimica et Cosmochimica Acta, 42, 547569 (1978).Google Scholar
[5] Frondel, C., Systematic Mineralogy of Uranium and Thorium. Geological Survey Bulletin, US Government Printing Office, Washington. 1064, 400p (1958).Google Scholar
[6] Finch, R.J. and Ewing, R.C, Journal of Nuclear Materials 190, 133156 (1992).Google Scholar
[7] Vochten, R., Huybrechts, W., Remaut, G., and Deliens, M., Physics and Chemistry of Minerals, 4, 281290 (1979).Google Scholar
[8] Vochten, R. and Deliens, M., Physics and Chemistry of Minerals, 6, 129143(1980).Google Scholar
[9] Murakami, T., Ohnuki, T., Isobe, H., and Sato, T, Am. Mineral (1997) (in press).Google Scholar
[10] Nuffield, E. W., Am. Mineral, 476488(1953).Google Scholar
[11] Miller, S.A. and Taylor, J.C., Zeitschrift fair Kristallographie, 177, 247253(1986).Google Scholar
[12] Stergiou, A.C. and Rentzeperis, P.J., Zeitschrift flir Kristallographie 205, 17 (1993).Google Scholar
[13] Rossman, G. R. in Reviews in Mineralogy, vol. 18, edited by Harthorne, F. C., Mineralogical soc. of America, 193206(1988).Google Scholar
[14] Rao, C.N. R., Chemical Applications of Infrared Spectroscopy. Academic press, New York and London, 349351 (1963).Google Scholar
[15] Russell, J. D., in A Handbook of Determinative Methods in Clay Mineralogy edited by Wilson, M. J., Chapman and Hall, New York, 133173(1987).Google Scholar
[16] Hoekstra, H. R., and Siegel, S., J.Inorg. Nucl. Chem, 35,761779(1973).Google Scholar
[17] Atohl, F. V., and Smith, D. K., Am. Mineral, 66, 610625 (1981).Google Scholar
[18] Weigel, F., and Hoffmann, G., J. less. comm. metals, 44, 99123 (1976).Google Scholar
[19] Vochten, R., Poret, P., and Goeminne, A., Am.Mineral, 104, 457467 (1961).Google Scholar
[20] Snelling, A.A, Geologic setting, Alligator Rivers Analogue Project Final Report 2, 118 p (1992). Australian Nuclear Science and Technology Organisation, Sydney.Google Scholar