One-Stage Adsorption Treatment of Liquid Radioactive Wastes with Complex Radionuclide Composition

The development of new materials and technologies for effective treatment of liquid radioactive waste is an urgent task. In present work, the novel Ti-Ca-Mg phosphate sorbents were developed. Sorbents were characterized by X-ray diffraction (XRD), Fourier transmittance infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and N 2 adsorption-desorption techniques. The influence of the chemical composition of mixed Ca-Mg-Ti phosphate sorbents and solution pH and the nature of the radionuclide on the sorption efficiency of 137 Cs, 85 Sr, and 60 Co radionuclides were determined. The obtained materials demonstrated excellent affinity towards 137 Cs, 85 Sr, and 60 Co radionuclides ( K d reached up to 10 5 mL g −1 ). For all Ti-Ca-Mg phosphates, an increase in the sorption efficiency of 137 Cs with an increase in the titanium content was observed. It was shown that the samples of Ti-Ca-Mg phosphates containing of 33–60 wt% titanium effectively removed 137 Cs, 90 Sr, and 60 Co radionuclides at pH 8.0–11.0. The prepared Ti-Ca-Mg phosphate sorbents are promising for one-stage treatment of aqueous solutions of complex composition from 137 Cs, 85 Sr, and 60 Co radionuclides and could be used for development of advanced technology for liquid radioactive waste treatment.