Effect of Ionic Liquid on the Extraction of Actinides and Lanthanides(III) with Phosphorylureas from Nitric Acid Solutions

Effect of ionic liquid 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide on the extraction of U(VI), Th(IV), and lanthanides(III) from nitric acid solutions with phosphorylureas RR'P(O)NHC(O)NHC₈H₁₇-n that differ in the nature of substituents at the phosphorus atom has been studied. A considerable synergistic effect has been revealed on the extraction of metal ions in the presence of the ionic liquid in organic phase. The stoichiometry of extracted complexes has been determined. The influence of extractant structure, organic diluent nature, and HNO₃ concentration in aqueous phase on the efficiency of metal ions extraction into organic phase has been considered.