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The surface reactivity of hollandite in aqueous solution

Published online by Cambridge University Press:  03 March 2011

D.K. Pham
Affiliation:
Division of Science and Technology, Griffith University, Nathan, Queensland 4111, Australia
S. Myhra
Affiliation:
Division of Science and Technology, Griffith University, Nathan, Queensland 4111, Australia
P.S. Turner
Affiliation:
Division of Science and Technology, Griffith University, Nathan, Queensland 4111, Australia
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Abstract

Hollandite, [BaxCSy][Ti, Al)3+2x+y Ti4+8−2x+y]O16, has been subjected to aqueous chemical attack at 75 and 150 °C. The resultant surface alterations have been monitored by solution analysis, SEM/TEM investigations, and surface analysis. The evolution of the solid/solution system can be described by the following mechanisms: There is a near-instantaneous release of Cs and Ba from reactive surface sites, followed by relatively rapid dissolution of the first few monolayers. The release of Al drives the pH to low values as a result of Al-OH hydroxylation and precipitation of AIO(OH) and/or AI(OH)3 species. The rate of dissolution is reduced by an order of magnitude or more by the formation of a thin and continuous Al(Ti)-rich surface layer. The layer remains stable and protective even under extreme hydrothermal conditions. This description has implications for the use of hollandite as a ceramic phase for disposal of high level nuclear wastes.

Type
Articles
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1Byström, A. and Bystrom, A.M., Acta Crystallogr. 3, 146 (1950).CrossRefGoogle Scholar
2Kesson, S. E. and White, T. J., Proc. R. Soc. London A405, 73 (1986); A408, 295 (1986).Google Scholar
3Fielding, P. E. and White, T. J., J. Mater. Res. 2, 387 (1987).CrossRefGoogle Scholar
4McCarthy, G. J., in Proc. Conf. on High Level Radioactive Solid Waste Forms, NUREG/CP-0005 (1978), p. 623.Google Scholar
5McCarthy, G. J., Komarneni, S., Scheetz, B. E., and White, W. B., in Scientific Basis for Nuclear Waste Management I, edited by McCarthy, G. J. (Plenum Press, New York, 1979), p. 329.CrossRefGoogle Scholar
6McCarthy, G.J., White, W. B., Roy, R., Scheetz, B. E., Komarneni, S., Smith, D. K., and Roy, D. M., Nature 273, 216 (1978).CrossRefGoogle Scholar
7Elliot, M. N. and Auty, D. B., UKAEA Rep. AERE-R-5151 (1967).Google Scholar
8Savage, D. and Chapman, N. A., in Geochemistry of Radioactive Waste Disposal, edited by Bird, G. W. and Fyfe, W. G., Chem. Geol. 36, 59 (1982).Google Scholar
9Myhra, S., Smart, R. St. C., and Turner, P. S., Scanning Microscopy 2, 715 (1988).Google Scholar
10Segall, R. L., Myhra, S., Smart, R. St.C., and Turner, P.S., Final Report NERDDC Project No. 80/0049, Aust. Gov. Publ. Off. (1985).Google Scholar
11Myhra, S., Smart, R.St.C., Turner, P. S., and Neall, F. B., Final Report NERDDC Project No. 883142, Aust. Gov. Publ. Off. (1987).Google Scholar
12Pham, D. K., Neall, F. B., Myhra, S., Smart, R.St.C., and Turner, P.S., in Scientific Basis for Nuclear Waste Management XII, edited by Lutze, W. and Ewing, R.C. (Mater. Res. Soc. Symp. Proc. 127, Pittsburgh, PA, 1989), p. 231.Google Scholar
13Turner, P. S., Jones, C. F., Myhra, S., Neall, F. B., Pham, D. K., and St. C. Smart, R., in Proc. NATO-ASI: Surfaces and Interfaces of Ceramic Materials, Oleron, France, 1988, edited by Du-four, J-C. (Kluwer Academic Publishers, Dordrecht, The Netherlands, 1989), p. 663.Google Scholar
14Jostsons, A., Smith, K. L., Blackford, M. G., Hart, K. P., Lumpkin, G. R., McGlinn, P., Myhra, S., Netting, A., Pham, D. K., Smart, R. St. C., and Turner, P. S., Final Report NERDDP Project No. 1319 (1990).Google Scholar
15Mendel, J. E., Nucl. Chem. Waste Manage. 3, 117 (1982).CrossRefGoogle Scholar
16Kastrissios, T., Stephenson, M., Turner, P. S., and White, T. J., in Proc. 11th Int. Congress on Electron Microscopy, edited by Imura, T., Maruse, S., and Suzuki, T., Tokyo (1986), Vol. 2.Google Scholar
17Kastrissios, T., Stephenson, M., and Turner, P. S., J. Am. Ceram. Soc. 70, C-144 (1987).CrossRefGoogle Scholar
18Myhra, S., Savage, D., Atkinson, A., and Rivière, J. C., Am. Mineral. 69, 902 (1984).Google Scholar
19Wolery, T. J., The EQ3/6 Software Package, Lawrence Livermore Laboratory, UCRL-52658 (1979).Google Scholar
20Lumpkin, G. R., Smith, K. L., and Blackford, M. G., J. Mater. Res. 6, 2218 (1991).CrossRefGoogle Scholar
21Myhra, S., Atkinson, A., and Riviere, J. C., J. Am. Ceram. Soc. 67, 223 (1984).CrossRefGoogle Scholar
22Myhra, S., Pham, D. K., Smart, R.St.C., and Turner, P.S., in Science of Ceramic Interfaces, edited by Nowotny, J. (Elsevier, Amsterdam, 1991), pp. 569606.Google Scholar