The alteration of CsAlSi5O12, a possible host for 137Cs in tailored nuclear waste ceramics, was studied under simulated nuclear waste repository conditions of 100°, 200°, and 300°C with a confining pressure of 30 MPa. The cesium radiophase was found to be quite stable in water or 3N CaCl2, or 3N MgCl2 but not in 3N NaCl or 3N KCI or a bittern brine. The acid resistance of CsAlSi5O12 can be deduced from its stability in hydrothermal MgCl2 brine. Possible reaction mechanisms include the formations of pollucite and quartz in deionized water and the formation of Na or K feldspars and quartz in the presence of NaCl or KCl brines, respectively. A comparison of the various cesium aluminosilicates indicates that pollucite (CsAlSi2O6) is the best candidate for cesium‐137 immobilization.
|Number of pages
|Journal of the American Ceramic Society
|Published - Jun 1983
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Materials Chemistry