137Cs, 85Sr and 60Co sorption from model solutions of low activity liquid radioactive waste by modified oil shale

Abstract

The results of the study of cesium, strontium, cobalt radionuclides sorption from model solutions simulating liquid radioactive waste on promising sorbents based on thermally modified oil shale are presented. The dependency of texture parameters obtained from the results of nitrogen adsorption-desorption on the treatment method of oil shale and their relationship to sorption parameters such as distribution coefficient and removal efficiency was discussed. Understanding how pore characteristics affect the sorption activity of such complex systems as sorbents is important for the creation of radionuclide sorption materials with improved characteristics. The efficiency of sorption of cesium, strontium and cobalt radionuclides was rather high for sorbent samples: the distribution coefficient was about 103–104 ml/g with a removal efficiency of more than 66 %. The most effective sorbent was obtained from oil shale with a heating rate of 5 deg/min without subsequent steam treatment, which is recommended to be used for low-active radioactive waste treatment.