Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-25T17:37:47.384Z Has data issue: false hasContentIssue false

Durability of Borosilicate Glass Compositions for the Immobilisation of the UK's Separated Plutonium Stocks

Published online by Cambridge University Press:  01 February 2011

Mike T. Harrison
Affiliation:
Nexia Solutions Ltd, The British Technology Centre, Sellafield, Seascale, Cumbria, CA20 1PG, UK.
Charlie R. Scales
Affiliation:
Nexia Solutions Ltd, The British Technology Centre, Sellafield, Seascale, Cumbria, CA20 1PG, UK.
Get access

Abstract

Several glass compositions are currently under investigation for immobilisation of the separated PuO2 that has been produced as a result of civil nuclear fuel reprocessing in the UK. Whilst a final decision on the fate of what ultimately will be over 100 tonnes of plutonium has yet to be made, all options for the disposition of this material are currently being investigated by Nexia Solutions Ltd on behalf of the Nuclear Decommissioning Authority (NDA).

As one of the immobilisation options, vitrification in borosilicate glass could potentially provide a criticality-safe and stable waste form with durability suitable for long term storage and subsequent repository disposal. From an initial experimental survey of potential candidates, three borosilicate compositions were selected for a more detailed study of the waste loading and chemical durability: lanthanide borosilicate (LaBS), alkali tin silicate (ATS) and high-lanthanide alkali borosilicate (modified-MW). In these inactive tests, hafnium was used as the surrogate for plutonium. This paper describes a range of static leach tests that were undertaken in order to understand the overall durability of the waste forms, as well as the release rates of the Pusurrogate when compared to any neutrons poisons present in the glass. For the LaBS compositions it was found that the release rate of gadolinium was potentially slightly higher than that of hafnium, although both were as low as 10-5 to 10-6 g m2 day-1. The potential implications for long-term repository behaviour are discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 2008

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

1 Scales, C. R., Maddrell, E. R., and Harrison, M. T. “Options for the Immobilisation of UK Civil Plutonium”, WM'07 Conference, February 25 – March 1, 2007, Tucson, AZ. Google Scholar
2 Harrison, M. T., Scales, C. R., Bingham, P. A., and Hand, R. J., Mat. Res. Soc. Symp. Proc 932 (2007).Google Scholar
3 Harrison, M. T. and Scales, C. R., MRS 2007: Scientific Basis for Nuclear Waste Management XXXI (presented at this meeting).Google Scholar
4 Bibler, N. E., Ramsey, W. G., Meaker, T. F., and Pareizs, J. M., Mat. Res. Soc. Symp. Proc. 412, 6572 (1996).Google Scholar
5 Marra, J. C., Peeler, D. K., and Jantzen, C. M., WSRC-TR-2006-00031, Washington Savannah River Company, Aiken, SC, 2006.Google Scholar
6 Zamecnik, J. R., Jones, T. M., Miller, D. H., Herman, D. T., and Marra, J. C., WM'07 Conference, February 25 – March 1, 2007, Tucson, AZ. Google Scholar
7 Bates, J. K., A. J. G. Ellison, Emery, J. W., and Hoh, J. C., Mat. Res. Soc. Symp. Proc. 412, 5764 (1996).Google Scholar
8 Riley, B. J., Vienna, J. D., and Schweiger, M. J., Mat. Res. Soc. Symp. Proc. 608, 677682 (2000).Google Scholar
9 Darab, J. G., Li, H., and Vienna, J. D., J. Non-Cryst. Solids 226, 162175 (1998).Google Scholar
10 Darab, J. G., Li, H., Schweiger, M. J., Vienna, J. D., Allen, P. G., Butcher, J. J., Edelstein, N. M., and Shuh, D. K., Plutonium Futures: The Science, Santa Fe, NM, August 25-27, 1997.Google Scholar
11 Fortner, J. A., Buck, E. C., Ellison, A. J. G., J. K., and Bates, Ultramicroscopy 67, 7781 (1997).Google Scholar
12 Lopez, C., Deschanels, X., Bart, J. M., Boubals, J. M., Auwer, C. Den and Simoni, E., Journal of Nuclear Materials 312, 7680 (2003).Google Scholar
13 Cachia, J.N., Deschanels, X., Auwer, C. Den, Pinet, O., Phalippou, J., Hennig, C. and Scheinost, A., Journal of Nuclear Materials 352, 182189 (2006).Google Scholar