Compositional Dependence of Glass Corrosion due to the Crystallization of Nepheline

Thesis (Ph.D.), Materials Science, Washington State UniversityVitrification of Hanford high-level nuclear waste is a complex process, which is of great significance to those residing in the state of Washington. One characteristic of the vitrified product, the chemical durability, can be high impacted by the deleterious crystallization of aluminosilicates and lead to a large decrease in the corrosion resistance of the vitrified product. Therefore, this work seeks to understand the influence of starting glass composition on the crystallization behavior of quaternary, quinary, and complex glasses. Techniques employed through with work include X-ray diffraction, Raman Spectroscopy, electron probe microanalysis, nuclear magnetic resonance, and synchrotron X-ray and neutron total scattering. It was determined that nepheline composition and microstructure was influence by starting melt composition and heat treatment temperature schedule. Additionally, mixed alkali effects influence crystallization extent and phase assemblage, boron speciation varies upon large fraction of crystallization, and a comparison of cation coordination number between glass and crystalline reference offers a metric for crystallization behavior for a wide range of silicate glasses.Washington State University, Materials ScienceBy student request, this dissertation cannot be exposed to search engines and is, therefore, only accessible to Washington State University users