Sorption of 137Cs and 90Sr by Chemically Modified Humic Acids

The sorption characteristics of modified humic acid-based sorbents obtained from peat from the Gurovskoye deposit are studied. The functional and elemental composition of the sorbents is determined, and the molecular weight characteristics of the sorbent components are analyzed. The sorption of 137 Cs and 90 Sr from liquid media depends on the pH value and the type and concentration of competing cations. The maximum adsorption capacity was calculated by fitting the obtained sorption isotherms to the Langmuir equation: the highest values ​​are achieved on HA-2 (257 mg Cs/g) and HA-5 (310 mg Sr/g). The dependence of the sorption-selective characteristics of the sorption materials with respect to cesium and strontium was determined depending on the functional composition. The humic acid-based sorbents are recommended for the extraction of cesium and strontium radionuclides in a wide range of liquid media, including environmental objects, based on the results of this study.