Comparison of sodium zirconium phosphate-structured HLW forms and synroc for high-level nuclear waste immobilization

摘要

The incorporation of (a) Cs and Sr as; (b) simulated actinides, and (c) simulated Purex waste in sodium zirconium phosphate (NZP) has been studied. The samples were prepared by sintering, by hot pressing and by hot isotatic pressing in metal bellows containers. The short-term chemical durability of the phosphate-based material containing Purex waste was within an order of magnitude of that for Synroc-C, as measuired by 7-day MCC-1 tests at 90 deg C. The dissolution behaviour showed evidence of re-precipitation phenomena, even after times as short as 28 days. Potential for improvement of NZP-based ceramics for HLW management is discussed.