Extraction of Lanthanides(III) from HClO4Solutions with Bis(diphenylphosphorylmethylcarbamoyl)alkanes

Novel polyfunctional neutral organophosphorus compounds, namely bis(diphenylphosphoryl-methylcarbamoyl)alkanes of general formula [Ph2P(O)CH2C(O)NH]2(CH2)n (I-III; n = 3, 5, 8), were synthesized and studied as extractants for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y from perchloric acid solutions. The influence of both of HClO4 concentration in the aqueous phase and that of the extractant in the organic phase on the extraction of metal ions is considered. The stoichiometry of the extracted complexes has been determined. Bis(diphenylphosphorylmethylcarbamoyl)alkanes II and III possess a higher extraction efficiency towards Ln(III) than their monoanalogue Ph2P(O)CH2C(O)NHC9H19. The potentialities of polymeric resin impregnated with bis(diphenylphosphorylmethylcarbamoyl)pentane II for the preconcentration of lanthanides(III) from perchloric acid solutions are demonstrated.