Unique extraction of U(VI), Pu(IV), Am(III) and Eu(III) from nitric acid medium using a phosphonium based ionic liquid consisting of novel anion, 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate – Dual solvent behavior

Abstract

Abstract Phosphonium based ionic liquid with a novel anion, 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate (HfAc) was synthesized and characterized by elemental analysis, 31P and 13C NMR. The functionalized ionic liquid showed interesting solvent extraction behavior for U(VI), Pu(IV), Am(III) and Eu(III) from the nitric acid medium when used in conjunction with toluene as diluent. Kinetics of extraction was found to be fast with equilibrium being attained within 15\xa0min. The acid dependency of the distribution ratios for the radionuclides showed two different mechanisms at pH medium as well as at higher nitric acid concentration showing dual solvent behavior. The solvent was found to be reusable for at least six cycles when regenerated using hexafluoroacetylacetone prior to each cycle of extraction. Stripping of the loaded elements from the solvent was found to be feasible using a complex mixture of Guanidine carbonate and EDTA. The solvent showed significant distribution ratio of Eu(III) even in presence of higher concentration of Eu i.e. 30\xa0mM. .