The mechanism of106Ru(III),106RuNO(II),144Ce(III),147Pm(III),85Sr(II),131I−,35SO
, and H232PO
radionuclide sorption on hydrated ferrous, ferric, aluminium and chromic hydrated oxides was studied. The dependence of sorption
on the pH has shown that in a certain range of pH values it is the ion exchange of the radionuclide for a proton or a hydroxyl
group of the oxide that probably plays a decisive role in the sorption process. The sorption depends considerably on the pH
in the whole range of studied, but its decrease with cations in alkaline media and its increase with I− ion in acidic media does not agree with the above sorption mechanism. Similarly, the course of the dependence of sorption
on the sorbent concentration does not indicate ion exchange to be the only mechanis, but it indicates a more complicated sorption
process. Probably the sorption of colloidal forms of the radionuclides proceeds, too.