Uranium extraction with modified sorbents

Hydrometallurgical processing of uranium-containing raw materials generates a significant amount of liquid industry-related waste, namely waste solutions that require disposal. Sorption is known as one of the most effective methods for purifying liquid matters contaminated with radionuclides. Various modification options are being developed for the purpose of using natural sorbents and increasing their sorption capacity. The authors proposed the methods for modifying natural aluminosilicate and coal-mineral raw materials. Zeolite found at the Kusmurun deposit and shungite from the Koksu deposit were selected for the research. The methods are based on obtaining solid-phase extractants. It was proposed to modify natural sorbents with a mixture of tributyl phosphate and di2-ethylhexyl phosphoric acid in kerosene, as well as a mixture of phosphoric acid and polyacrylamide. It was demonstrated that the first method is preferable for zeolite, and the second one for shungite. The research addressed the sorption properties of modified sorbents in static and dynamic modes. Uranium sorption isotherms were plotted. The maximum sorption capacity and the Langmuir constant were calculated. The research allowed synthesizing an organopolymer based on shungite, glycidyl methacrylate, orthophosphoric, and hydroxyethyl diphosphoric acids. Its sorption properties were studied under dynamic conditions. Its sorption capacity was assessed in comparison with modified natural sorbents.