Effect of surfaces on glass waste form leaching

Abstract A promising method for providing backup protection against the dispersion of radioactive waste by water is to incorporate the waste in a glass matrix. Although diffusion and network dissolution are generally considered to be rate-controlling, rates of attack of glass by water and aqueous solutions are best rationalized when the composition and microstructure of the glass surface are taken into account. In order to account for those effects, a leaching model emphasizing the processes occuring at the solid waste form-leachant interface is presented. Although the model leads rapidly to situations which are no longer easily amenable to analytical solutions, valuable physical insight can still be gained by determining the asymptotic behaviors of leach rates in the short- and long-term.