Behaviour of radionuclides in aqueous solutions and their sorption on hydrated oxides and some insoluble salts

The present knowledge of the behaviour of radionuclides in trace concentrations in aqueous solutions is reviewed and a probable mechanism of formation of radionuclide colloidal dispersions (radiocolloids) is outlined. The physico-chemical characteristics of radiocolloids (size, relative weight, self-diffusion coefficient values etc.) are given and the experimental results of studies of radiocolloids and radionuclide adsorption on the surface of various materials are summarized. A qualitative explanation of the mechanism of radionuclide sorption on hydrated oxides and insoluble salts of monobasic and dibasic acids is suggested, and the physico-chemical characteristics of these sorbents and examples of their application to the sorption and separation of radionuclides are given. The isotope exchange of radionuclides on insoluble salts is also treated. (author)