Effects of M2O3 (M = Bi, Al) on silver vanadate glass for radioactive iodine immobilization

Abstract This study investigated the effects of Bi2O3 and Al2O3 on silver vanadate glasses for iodine immobilization. An iodine immobilization matrix was developed and examined with M2O3 (M = Bi, Al) as additives for a AgI-Ag2O-V2O5 glass system. Immobilization was confirmed at 800 °C after 1 h of melting without significant loss of the elements that constituted the glass, excluding aluminum. The loading of iodine in the matrix was approximately 30–36% by weight, excluding oxygen. Normalized releases of all elements obtained were below the order of 10−1 g/m2, which satisfies the USA regulation (2 g/m2). The structural factors that influenced the chemical durability of the glass and suppressed iodine release were discussed. The addition of M2O3 (M = Bi, Al) suppressed iodine release by the formation of a VO4 tetrahedron from the V2O5 glass matrix. The release of silver was not as suppressed as that of iodine.