Synthesis of high mechanical strength and excellent radiation resistance NaX zeolite microspheres via geopolymer in situ conversion and their adsorption study of 137 Cs and 90 Sr

作者：Min Yi, Lin Shao, Xuemin Cui, Kaituo Wang · 发表于：Journal of Advanced Ceramics · 年份：2025 · DOI：10.26599/jac.2025.9221123 · 被引用次数：16 · 研究领域：Chemical Synthesis and Characterization、Zeolite Catalysis and Synthesis、Nuclear materials and radiation effects

For the remediation of radionuclides (e.g., 137 Cs and 90 Sr) in nuclear wastewater, conventional materials struggle to simultaneously exhibit excellent adsorption performance, high mechanical strength and good irradiation resistance. Herein, a kind of high-strength NaX zeolite microspheres with 75-150 μm particle size (GXU-GNaXs, compressive strength: 19.21 MPa, Vickers hardness: 216.30) were prepared for the first time by the in-situ conversion of geopolymer technology under normal pressure at 105 ºC for 12 h. The results showed that GXU-GNaXs achieved removal efficiency exceeding 90 % for Cs + and Sr 2+ within 20 min at dosage of 0.8 g·L -1 , following pseudo-second-order and Langmuir model with maximum saturated adsorption capacities of 138.30 and 153.60 mg·g -1 at 45 and 30 min, respectively. Meanwhile, GXU-NaXs maintained >98 % structural stability and adsorption capacity after 500 kGy γ-irradiation, which had the potential for excellent stability in the nuclear environment. GXU-NaXs also exhibited good dynamic adsorption effect at flow rate of 6 mL·min -1 , and the removal efficiency after three cycles remained 97.89 and 56.39 % for Cs + and Sr 2+ , respectively, demonstrating GXU-NaXs had good feasibility for industrial applications. GXU-NaXs showed good removal capacity and selectivity in complex seawater matrices for Cs + and Sr 2+ . Density functional theory calculations revealed adsorption energies of -2.43 (Cs + ) and -3.52 eV (Sr 2+ ), while SEM/EDS, T...