Aluminum (Iron) Phosphate Glasses Containing Rare Earth and Transuranium Elements: Phase Composition, Oxidation State of Np and Pu, and Hydrolytic Durability

Abstract

Samples of aluminum (iron) phosphate glasses containing weighable amounts of rare earth and transuranium elements were synthesized. The quenched glasses obtained are X-ray amorphous, and in the course of annealing they undergo partial crystallization with segregation of a poorly soluble phase of monazite structure. However, the hydrolytic durability of the glasses remains on the level meeting the requirements to immobilized high-level waste (no more than 10^–7 g cm^–2 day^–1). Plutonium in the surface layer of the glass samples occurs in oxidation state IV, and neptunium, mainly in oxidation states IV and V.