Immobilization of a simulated HLW in phosphate based glasses/glass-ceramics by melt-quenching process

Abstract

In this paper, monazite-iron phosphate based glass-ceramics for immobilization of a simulated high-level nuclear waste (HLW) derived from the composition of a nuclear waste in China were prepared through a melt-quenching process. The effect of HLW incorporation on phases, structural features, aqueous durability and properties of the as-prepared wasteforms were investigated in detail. The results show that the waste loading can be significantly elevated by forming monazite (Ce, La, Nd)PO4 containing glass-ceramic wasteforms through the melt-quenching process. The obtained glass/glass-ceramic wasteforms show good aqueous durability (∼10−4 g m−2 d−1) and thermal stability. Moreover, the formation of monazite (Ce, La, Nd)PO4 phase in the wasteforms is discussed. The conclusions suggest that it is feasible to synthesize (Ce, La, Nd)PO4-phosphate glass-ceramic wasteforms through melt-quenching process and monazite-iron phosphate based glass-ceramics are potential candidates for immobilization of the HLW.