Phase Separation in the Glass Containing High Level Radioactive Waste

Abstract

The phase separation in the glass of the system Na₂O-B₂O₃-SiO₂-MoO₃ has been investigated as the basic study on the solidification of high level radioactive waste with glass.
The amount of MoO₃ or sham-waste to be introduced without phase separation into the glass increased with the substitution of B₂O₃ for SiO₂ in the basic glass composition.
Parameters for estimating the limiting amount of MoO₃ to be introduced into a glass of given composition were determined from experimental data, assuming the melt of the system Na₂O-B₂O₃-SiO₂-MoO₃ to be the regular solution of pseudo-binary system consists of two end members, Na₂MoO₄ and the remaining oxides. The limiting amount of waste to be introduced, estimated using the parameter for respective structural unit which is expected for a melt of given composition, agreed to the experimental result.