Immobilization of simulated waste into pure Gd2Zr2O7 pyrochlore without space occupancy design

In this study, different molar ratios of Nd:Ce were directly mixed with prepared pure Gd2Zr2O7 powders without space occupancy design. Samples were obtained by performing sparking plasma sintering (SPS) at 1750 degrees C for 5 minutes. X-ray diffraction (XRD) results show that maximum solid solubility of simulated radionuclides can reach 50 mol%. In addition, all samples with the maximum solid solubility have high compactness, and all elements are evenly distributed on the surface of the samples. The samples show a better crystallization effect as the molar ratio of Nd:Ce increases. The maximum solid solubility increases from 42 mol% to 50 mol% when the amount of Nd2O3 reaches 66 mol%.