Immobilization and bonding scheme of radioactive iodine-129 in silver tellurite glass

Abstract

Silver tellurite glasses with melting temperatures < 700 ��C were prepared to immobilize the 129I that normally volatilizes during high-temperature melting. Glasses have densities of 6.31 �� 0.1 g/cm3 and glass transition temperatures of 165 �� 3 ��C that provide thermal stability at the disposal site. Iodine waste loading in glasses was as high as 12.64 wt% of all metallic elements and 11.21 wt% including oxygen. Normalized elemental releases obtained from the product consistency test were well below US regulation of 2 g/m2. Iodines are surrounded by four Ag+ ions forming [Ag4I]3+ units that are further connected to tellurite network through bonds with non-bridging oxygens. ? 2017 Elsevier B.V.