Nd 2 O 3 immobilized by granite based glass–ceramics: composition, structure, and performance

Natural granite was considered for immobilizing nuclear waste Nd 2 O 3 (Nd 3+ simulated for An 3+ ). The structure and performance of pure granite were compared with Nd 2 O 3 doped granite sintered at 1500 °C. The introduced Nd 3+ distributed mainly in the glass network below the loading capacity (19 wt .%). Beyond that, tetrahedral SiO 4 units existed in a sheet form, while extra Nd 3+ precipitated as Nd 2 Si 2 O 7 . The doped Nd 2 O 3 improved the hardness (6.29–7.07 GPa) and density (2.19–2.71 g/cm 3 ) of matrix. Moreover, the solidified form presented NR Nd below 1.7 × 10 –6 g m −2 d −1 after 28 days. This work disclosed a potential host matrix for nuclear waste. Graphics abstract