Influence of the content of a surrogate of iron aluminate high-level wastes on the phase composition and structure of glassy materials for their immobilization

Alkali borosilicate glassy materials with high iron and aluminum oxide concentrations, which simulate vitrified high-level wastes from the Savannah River Site (United States) at their content ranging from 50 to 70 wt %, have been investigated using X-ray powder diffraction, optical and electron microscopy, and infrared spectroscopy. Quenched and slowly cooled samples containing 50 wt % wastes are glasses. Samples containing 60 and 70 wt % wastes, which were quenched on a metal slab, are predominantly glasses with an insignificant content of the spinel formed in a trevorite-magnetite solid solution. The slowly cooled samples also contain nepheline, and its amount increases with an increase in the waste content in the glassy materials.