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Static Dissolution of Uo2 in Interstitial Boom Clay Water

Published online by Cambridge University Press:  10 February 2011

K. Lemmens ,
C. Cachoir  and
P. Van Iseghem
K. Lemmens
Affiliation:
SCK•CEN, Boeretang 200, B-2400 Mol, Belgium.
C. Cachoir
Affiliation:
SCK•CEN, Boeretang 200, B-2400 Mol, Belgium.
P. Van Iseghem
Affiliation:
SCK•CEN, Boeretang 200, B-2400 Mol, Belgium.
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Abstract

Static dissolution experiments were performed with unirradiatcd UO2 in Boom Clay water. The objectives were (1) to measure the solubility of uranium species in Boom Clay water, with UO2 as the solid phase, and (2) to assess the impact of dissolved organic matter and carbonate concentration on this solubility. The tests were supported by calculations with geochemical codes to indicate possibly solubility controlling solid phases. The tests were performed in anoxic and reducing conditions, at 20 and 25°C. The following conclusions could be drawn: (1) Within 2 months in anoxic conditions, the uranium concentrations appear to approach saturation. (2) The “near-saturation” concentrations are between 2.4 and 7.8× 10−7 M. (3) The influence of the carbonate concentration and humic acids on the uranium concentration was apparently small, but the interpretation is hampered by pH and Eh variations. (4) The concentrations tend to be higher than the concentrations found in literature for similar Eh and/or pH conditions; this can probably be explained by small differences in experimental conditions. (5) The measured “near steadystate” uranium concentration in the real clay water agrees relatively well with the solubility calculated for uraninite. (6) Addition of sulfide species reduced the rcdox potential, but not the uranium concentrations, except in real Boom Clay water.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 556: Symposium QQ – Scientific Basis for Nuclear Waste Management XXII , 1999 , 1009
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

[1] Verdickt, W., De Interactie van Europium en Uranium met Boomnse Klei onder in situ omstandigheden, Thesis at Katholieke Universiteit Leuven, 1997, p. 77 Google Scholar
[2] Grambow, B., Spent fuel dissolution and oxidation. An evaluation of literature date, SKB Technical Report 89-13, Stockholm, Sweden, 1989, pp. 25–26 Google Scholar
[3] Ollila, K., Olin, M. and Lipponen, M., Radiochimica Acta 74, pp. 9–13 (1996)Google Scholar
[4] Bruno, J. and Puigdomenech, I., in Scientific Basis for Nuclear Waste Management XII, edited by Lutze, W. and Ewing, R.C. (Mater. Res. Soc. Proc. 127, Pittsburgh, PA 1989), pp. 887–896.Google Scholar
[5] Ollila, K. in Source term for Performance assessment of Spent Fuel as a waste form, Annual Report 1996 for EU-Programme “Nuclear fission Safety”, Contract No. FI4W-CT95-0004, 1997 Google Scholar
[6] Casas, I., Pablo, J. De, Gimenez, J., Molera, M. and Torrcro, M.E., in Source term for Performance assessment of Spent Fuel as a waste form, Annual Report 1996 for EU-Programme “Nuclear fission Safety”, Contract No. FI4W-CT95-0004, 1997 Google Scholar
[7] Ollila, K. in Scientific Basis for Nuclear Waste Management XX, edited by Gray, W.J. and Triay, I.R. (Mater. Res. Soc. Proc. 465, Pittsburgh, PA 1997), pp. 549–556.Google Scholar
[8] Ollila, K. in Source term for Performance assessment of Spent Fuel as a waste form, Annual Report 1997 for EU-Programme “Nuclear fission Safety”, Contract No. FI4W-CT95-0004, 1998 Google Scholar
[9] Lous, K. Le, Etude de la lixiviation du combustible usé en présence de matériaux d'environnement, Thesis at Universit6 de Paris Sud, 1997, p. 145 Google Scholar