Synthesis of Ceramic and Glass Ceramic Matrices with Immobilized Cesium Radionuclides for Active Zones of Ionizing Radiation Sources

Abstract

The present study was devoted to the development of alternative solutions related to replacement of highly dispersed powder of cesium chloride (137CsCl) used as a filler of active zones of g-radiation IRSs (ionizing radiation sources of the closed type) by safer and more efficient in operation highly compacted ceramic or glass ceramic material. An advanced method of fabrication of highly compacted (density of ~99.8 % of the theoretical one) aluminosilicate (artificial NaA zeolites) ceramic and glass ceramic matrices characterized with high construction strength (compression strength ~149 MPa) applicable for reliable immobilization of cesium radionuclides (leaching rate <10-5–10-6g/cm2×day) has been suggested. Unique matrices properties are ensured by advanced features of the technology of Spark Plasma Sintering (SPS) based on high-rate electro-pulse consolidation of the radioactive charge (adsorbed cesium content ~22.16 mass %) into thermodynamically stable ceramics or glass ceramics. The earlier unstudied features of the SPS consolidation of natural zeolite powders sorption-saturated with a radioactive cesium simulant are presented, including the dynamics of their compaction and specifics of phase and structural transformations under effect of irreversible spark plasma conditions.