Study on the removal of radionuclides in aqueous solution using inorganic adsorbents

Abstract

Removal of long lived radionuclides has been extensively studied in the case of separation and solidification of high level radioactive liquid waste and in controlling cooling water contamination from defective spent nuclear fuels in storage pools. Radionuclides such as $^{137}Cs$ and $^{85}Sr$ were removed from dilute aqueous solutions by means of inorganic adsorbents, MS-13X and chabazite. Adsorption data of radionuclides on the inorganic adsorbents were satisfactorily correlated by the Dubinin-Astakov(DA) equation. Gaussian type distributions of adsorption energies were obtained from the parameters of the DA equation by applying the condensation approach. A surface diffusion model was applied to estimate the intraparticle mass transfer of radionuclides. The adsorption model, which describes surface diffusion mechanism with the DA equation, satisfactorily simulated the adsorption behavior of radionuclides on zeolites in fixed bed adsorbers as well as in batch adsorbers.