Microwave sintering for rapid treatment of simulated Nd³⁺ and Sr²⁺ radioactive contaminated soil: exploring the influence of Nd:Sr mass ratio and mechanism

This study achieves the successful immobilization of simulated alpha- and beta-emitting radionuclides (Nd³⁺ and Sr²⁺, respectively) by incorporating them into a glass matrix through Nd₂O₃/SrSO₄ (Nd/Sr). Varying mixture concentrations (5–30 wt% with mass ratios Nd:Sr varied from 10:1 to 1:10) in simulated radioactive soils were subjected to microwave sintering at 1500 °C for 0.5 h. Comprehensive assessments, including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS), confirm the vitrification process’s efficacy. The vitrified sample exhibits an amorphous structure, smooth surface, and homogeneously distributed elements, highlighting microwave sintering as a promising method for the effective disposal of radioactive-contaminated soil.