Adsorption studies of cerium on lead dioxide from aqueous solutions

Cerium adsorption on lead dioxide was investigated as a function of pH, equilibration time, sorbate and sorbent concentrations. At pH 6, the distribution coefficient increased with increasing adsorbate concentration up to a maximum of 8.25 umol per dm3 beyond which it decreased with a further increase of cerium concentration in solution. The effect of certain other anions (citrate, EDTA, tartrate and oxalate) and cations (uranium(VI), thallium(IV), lead(II), chromium(III) and aluminium(III)) was to drastically reduce the adsorption of cerium. It was possible to separate cerium from ions such as iron(III), technetium(VII), indium(III), silver(I), mercury(II) and tantalum(V). A mean free energy of sorption was calculated (11.62 KJ per mol) using the Dubinin-Raduskevich equation. This corresponded to an ion exchange reaction. There are 46 references.