Characterization of Hydrated Surface Layers on Nuclear Waste Glasses by Infrared Reflectance Spectroscopy

Abstract

AbstractThe reaction between aqueous solutions and borosilicate glasses designed for commercial or defense waste immobilization produces a hydrated layer on the surface of the glass which can be characterized by infrared reflectance spectroscopy. Specular reflectance curves, obtained by Fourier transform infrared spectroscopy, can be deconvoluted by Kramers-Kronig analysis to obtain true absorption spectra. The pattern of Si-O stretching modes changes for alkali silicate glass, indicating changes in the network polymerization. The characteristic intense band of the borosilicate glasses simply changes intensity in a way that scales with degree of hydration. The progressive hydration of the glass surface also appears as a broad OH band which can be extracted from the reflectance curve by the deconvolution process.