Construction and potential application of metal oxide framework-graphene oxide for selective and efficient remediation of strontium from simulated liquid radioactive waste.

This research examines the extraction and elimination of 134Cs and 85Sr from simulated radioactive waste utilizing a novel composite material made of MnZnFe2O4-graphene oxide (MZFO-GO). The composite was synthesized and characterized through Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, elemental mapping, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The sorption behavior of 134Cs and 85Sr was systematically assessed under different experimental conditions, such as pH, contact time, and initial concentration. The findings indicated that the composite displayed significant selectivity for 85Sr, attaining removal efficiencies of 20.7% for 134Cs and 99% for 85Sr at a pH of 6. The analysis of sorption kinetics and isotherms was conducted utilizing pseudo-first-order, pseudo-second-order, Langmuir, and Freundlich models. The pseudo-second-order kinetic model demonstrated the most accurate representation of the adsorption process, suggesting that chemisorption is the primary mechanism involved. The Langmuir isotherm model indicates monolayer adsorption, with maximum retention capacities of 12.8 mg g-1 for Cs+ and 176.99 mg g-1 for Sr2+. Thermodynamic analyses indicated that the sorption of 85Sr onto MZFO-GO was both spontaneous and exothermic across the examined temperature range. The results indicate that MZFO-GO serves as an effective sorbent for the selective extraction of radioactive Sr2+ ions from simulated liquid radioactive waste, suggesting valuable applications in nuclear waste management.