Corrosion of the borosilicate glass R7T7 in a concentrated NaCl-brine. Experimental data and surface characterization

The corrosion of the inactive multicomponent borosilicate glass R7T7 was studied in a concentrated NaCl brine. Hydrothermal corrosion conditions were applied with fixed temperatures between 110 and 190xC and a pressure of 130 bar. Long term corrosionconditions, i.e. silica saturation in the leachate, were established by corrosion of glass powders with a narrow particle size distribution. Glass chips were corroded together with glass powders in order to provide flat corroded glass samples for surface analysis with X-ray photoelectron spectroscopy. The results indicate deviations from a linear time law for long term, which might be due to an enrichment of Na at the surface of corroded glass.