Ion exchangers in radioactive waste management Part X. Removal of barium ions from aqueous solutions by hydrous bismuth oxide using radiotracer technique

The uptake of barium ions at the micro and tracer concentration levels on synthesized bismuth oxide using the radiotracer technique has been studied and is found to be favoured at lower adsorptive concentrations and higher temperatures. The process follows a first order rate law with respect to the bulk ion concentration and obeys the Freundlich isotherm over the entire range of adsorptive concentration; the removal was found to increase with increasing pH. Based on thermodynamic data and the extremely low value of desorption, the process is confirmed to be irreversible in nature. Bismuth oxide does not exhibit any change in sorption characterisics due to irradiation with neutrons (3.85 × 106 neutrons/cm2/s) and gamma-rays (172 rad/h), showing it to be radiation stable. The findings suggest the possibility of using bismuth oxide in the treatment of radioactive wastes and effluents.