Can ionic liquids avoid third phase formation in solvent extraction?

The undesirable third phase is generally encountered in molecular diluent systems at high metal loading concentrations. Since the ionic liquids comprise entirely of ions, the use of an ionic liquid as diluent could stabilize the polar metal-solvate in organic phase and thus could prevent the third phase formation. To confirm this the extraction behavior of Eu(III) from nitric acid medium was studied in a solution of tetra-N,N,N',N'-octyldiglycolamide (TODGA) dissolved in the ionic liquid, 1-methyl-3-octylimidazolium bis(trifluoromethansulfonyl)imide ((C₈mim)(NTf₂)). Our results confirmed that ionic liquids prevent undesirable third phase formation. (author)