Vapor hydration of a simulated borosilicate nuclear waste glass in unsaturated conditions at 50 °C and 90 °C
Journal
RSC Advances
Journal Volume
5
Journal Issue
79
Start Page
64538
End Page
64549
ISSN
2046-2069
Date Issued
2015
Author(s)
Abstract
Vapor hydration of a simulated typical French nuclear intermediate-level waste (ILW) glass in unsaturated conditions has been studied in order to simulate its behaviour under repository conditions before complete saturation of the disposal site. The experiments were conducted for one year at 50 °C and 90 °C and the relative humidity (RH) was maintained at 92% and 95%. The glass hydration was followed by Fourier Transform Infra-Red spectroscopy (FTIR). The surface of the reacted glass was characterised by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The chemical and mineralogical composition of the alteration products were studied by Energy Dispersive X-ray Spectroscopy (EDX) and μ-Raman spectroscopy, respectively. The glass hydration increased with temperature and RH and led to the formation of a depolymerized gel layer depleted in alkalis. The glass hydration rate decreased with time and remained almost unchanged for the last three months of exposure. Overall, the ILW glass hydration rate was similar to that obtained with the SON68 high-level waste glass.
Subjects
Electron microscopy
Energy dispersive spectroscopy
Fourier transform infrared spectroscopy
Glass
High resolution transmission electron microscopy
Hydration
Radioactive waste disposal
Radioactive wastes
Scanning electron microscopy
Transmission electron microscopy
Waste disposal
X ray spectroscopy
Chemical and mineralogical compositions
Disposal sites
Energy dispersive X ray spectroscopy
Fourier transform infra red (FTIR) spectroscopy
High level waste
Intermediate level wastes
Nuclear waste glass
Unsaturated condition
Borosilicate glass
Publisher
Royal Society of Chemistry (RSC)
Type
journal article