LAUSR

Abstract The uptake of Th(IV) from acidic feed solutions was investigated by solid phase extraction using a Chromosorb W based extraction chromatography (XC) material containing Aliquat 336 in the resin pores. Increase in Th(IV) uptake was seen with increasing aqueous acid concentration conforming to an anion exchange mechanism. There was negligible Uranium uptake under identical conditions suggesting possible separation of the metal ions. The Th(IV) uptake data were subjected to kinetic modeling and the sorption isotherm models which clearly conformed to the pseudo-second order kinetics and Langmuir isotherm. Column studies were carried out to obtain breakthrough and elution profiles of Th4+ while UO22+ was not held onto the column. The separation of 234Th from 238U was studied with encouraging results and a separation scheme was proposed.