Extraction and recovery of cerium(IV) and thorium(IV) from sulphate medium by an α-aminophosphonate extractant

Abstract

In the present work, a novel α-aminophosphonate extractant (Cextrant 230) was synthesized for the extraction and recovery of cerium and thorium from sulphate medium. The introduction of amine group into the phosphate molecule would enhance the extraction of Ce(IV) and Th(IV). The effects of extractant concentration, H2SO4 concentration and temperature on the metal extraction were investigated in detail. It was found that the extraction of Ce(IV), Th(IV) and REs (La, Gd, Yb) in sulphate medium decreased in the following order: Ce(IV)>Th(IV)>REs(III). A solvent extraction process to extract and recover cerium and thorium from bastnasite leaching was proposed, in which the purities of cerium and thorium products reached 99.9% and 99% with yield of 92% and 98%, respectively.