Analytical Sciences

Abstract − Analytical Sciences, 30(8), 783 (2014).

A Specific Synergistic Effect in Ionic Liquid Chelate Extraction Based on Neutral Ternary Chloro-complex Formation
Motoya SAKATO* and Naoki HIRAYAMA*,**
*Department of Chemistry, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
**Research Center for Materials with Integrated Properties, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
In the chelate extraction of zinc(II) into an ionic liquid (IL), 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (C4mimTf2N), with 8-(p-toluenesulfonamido)quinoline (Htsq), the co-existence of a certain amount of chloride anion in the aqueous phase resulted in an enhancement of the extractability. This enhancement did not occur at all in that into chloroform, a conventional organic extraction solvent. The specific synergistic effect was based on the dominant extraction of a neutral ternary complex, Zn(tsq)Cl, which is unstable in molecular organic solvents.