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Effect of a Siliceous Additive in a Clay Engineered Barrier on Aqueous Corrosion of R7T7 Nuclear Waste Glass

  • N. Godon (a1), Z. Andriambololona (a1) and E. Vernaz (a1)

Abstract

Previous tests have shown that glass is highly corroded in the presence of smectite 4a, a clay under consideration for use as a repository engineered barrier material. Alteration experiments with French R7T7 glass were therefore conducted in moist clay media containing 5 wt% of a siliceous additive. Five siliceous materials were tested: silica gel, pozzolana, window glass, R7T7 glass frit and R7T7 glass, all in powder form. Following an initial 28-day preconditioning period during which the clay/additive/leachant system was allowed to reach equilibrium, a glass specimen was placed for 7 or 28 days in the moist clay medium. Glass alteration was characterized by the mass loss and by surface analysis. After 28 days in contact with the silica gel and with the three glass powders the mean glass corrosion rate calculated from the mass loss values was about 0.01 g.m−2d−1, versus 1.4 g·m−2d−1 with clay alone and 0.3 g·m−2d−1 with pozzolana. The use of a suitable additive can thus considerably attenuate the corrosive effects of moist smectite in contact with R7T7 glass.

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References

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1. Godon, N., Effet des matériaux d'environnement sur l'altération du verre nucléaire R777: Influence des argiles, PhD thesis: Université d'Orlhans, France (1988).
2. Godon, N., Vernaz, E.Y., Thomassin, J.H. and Touray, J.C., “Effect of Environmental Materials on Aqueous Corrosion of R7T7 Glass”, Mat. Res. Soc. Symp. Proc., 127 (1989) pp 97104.
3. Godon, N. and Vernaz, E.Y., “R7T7 Nuclear Waste Glass Behavior in Moist Clay: Role of the Clay Mass/Glass Surface Area Ratio”, Mat. Res. Soc. Symp. Proc., 176 (1990) pp 319326.
4. Vernaz, E.Y. and Godon, N., “Key Parameters of Glass Dissolution in Integrated Systems”. Mat. Res. Soc. Symp. Proc., 212, (1991) pp 1930.
5. Fillet, S., Méanismes de corrosion et comportement des actinides dans le verre nucléaire R777, PhD thesis: Université de Montpellier, France (1987).
6. Advocat, T., Les méanismes de corrosion en phase aqueuses du verre nucléaire R7T7: Approche expérimentale, essai de modélisation thermodynamique et cinétique, PhD thesis: Université de Strasbourg, France (1991).

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