Extraction of rare-earth elements(III) from nitric acid solutions with bis(diarylphosphorylmethyl)benzenes

Extraction of micro quantities of rare-earth elements(III) from HNO 3 solutions as complexes with bis (diarylphosphorylmethyl)benzenes depending on the nature of organic diluent and HNO 3 concentration in equilibrium aqueous phase was studied, the stoichiometry of extracted complexes was determined. The effect of structure of a bridge between two phosphine oxide fragments in an extractant molecule on the efficiency and selectivity of rare-earth elements(III) extraction was considered.