High capacity and aqueous stability immobilization of simulated trivalent actinides by zircon-based borosilicate glass-ceramics: Synergistic effect between the crystal lattice and glass network immobilization

Abstract

The development of matrix with high capacity and stability immobilization of nuclear waste is highly desirable. Herein, new type of zircon-based borosilicate glass-ceramics (ZBGC) with high immobilization capacity and excellent aqueous stability was prepared and applied to immobilize simulated trivalent actinide (Nd). The effects of Nd doping and sintering temperature on the microstructure and phase composition of the obtained ZBGC were researched. The experimental suggested that high ZrSiO4 formation rate (97.49 wt%) was obtained by tuning the Nd content and sintering temperature. The record high immobilization capacity of Nd in ZGBC (18 at%) was achieved owing to the synergistic effect between the crystal lattice and glass network immobilization. Additionally, the obtained Nd-doped ZBGC exhibited excellent aqueous stability (∼10−6 g m−2 d−1) due to the high compactness. The results demonstrated that ZBGC with high immobilization capacity and aqueous stability could be potential matrix for actinides immobilization.