Effect of Composition on Local Environment of Sulphate in Silicate Glasses

We will study the effects of changes in composition and structure of alkali silicate and alkali-alkaline earth silicate glasses on its sulphate incorporation capacities. Total scattering data for 20 glasses on GEM will be measured. Composition change was introduced by replacing the sodium oxide with lithium oxide and calcium oxide with barium oxide. Each glass composition was doped with sulphur to its maximum solubility limit till a salt layer formed on the surface. This ensured that maximum sulphur capacity for each composition was achieved and direct comparisons could be made between sulphur solubility and glass composition. Neutron diffraction data on the doped glasses and their sulphur free equivalents combined with XRD, NMR and Raman spectroscopy will help to understand the local environment around sulphur in the glass and effects of sulphur incorporation on glass structure.