SEM/EDS Analysis of Boron in Waste Glasses with Ultrathin Window Detector and Digital Pulse Processor

Abstract

Borosilicate glass has been selected for immobilizing radioactive wastes because of its chemical durability and ability to incorporate many different elements.Boron is an important component in the borosilicate waste glass: its addition facilitates the processibility of glass by lowering its viscosity. In addition, the release of boron is used to measure the corrosion progress during laboratory tests that determine the durability of a glass. Analysis of boron that is present in waste glasses and in the reaction products that form during the reaction of glass is important for understanding the reaction kinetics and mechanism of glass corrosion.Waste glasses have been previously analyzed for B in our laboratory by wavelength-dispersive spectrometry (WDS) in SEM. As can be deduced from Fig. 1, WDS analysis of waste glasses with B concentrations up to 4 wt% yields a line with a slope of 0.4 counts/s/wt%, with a resolution of ˜0.5 wt%. However, EDS is analytically more convenient and advantageous because its high detection efficiency and its ability to simultaneously acquire an entire spectrum. The innovation of the ultra-thin window has made it possible for an EDS to detect soft x-rays, which are absorbed by a normal Be window.