Effect of V2O5, ZrO2, and waste components on chemical durability of a Japanese simulated high-level waste glass

Abstract

Chemical durability tests were conducted on Japanese simulated high-level waste (HLW) glasses for 48 h, and the effect of addition of V2O5, ZrO2 and waste components on the leaching rate were examined. We found that the normalized leaching mass loss of silicon and boron of waste-free glass became slow after 20 h, whereas linearly increased with increasing time in waste-bearing glass. This indicates importance of consideration of waste components in the chemical durability test of the HLW glass. Combined addition of V2O5 and ZrO2 with waste-bearing glasses has significantly reduced the chemical durability. It is estimated that the change of Si with Zr and V in a network-forming site reduced the Si-O-Si bonds and hindered the gel formation that protects glass.