Analytical Sciences

Evaluation of a Hydrophilic Ionic Liquid as a Salting-out Phase Separation Agent to a Water–Tetrahydrofuran Homogeneous System for Aqueous Biphasic Extraction Separation

Naoki HIRAYAMA,*1,*2 Takaaki HIGO,*3 and Hisanori IMURA*4

*1 Department of Chemistry, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
*2 Research Center for Materials with Integrated Properties, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
*3 Division of Material Chemistry, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
*4 Division of Material Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan

The use of a hydrophilic ionic liquid (IL), 1-butyl-3-methylimidazolium chloride (C₄mimCl), as a salting-out phase separation agent to a water–tetrahydrofuran homogeneous system was studied for possible applications to novel aqueous biphasic extraction separation. The IL showed a salting-out phase-separation ability. Also, differences in the polarity between the formed two phases were smaller than that when using NaCl as a salting-out agent. This result suggested that C₄mimCl remaining in water-rich phase acts not only as a salting-out agent, but also a component of a mixed-solvent. Possible uses of C₄mimCl/NaCl mixed salting-out agent system were also discussed.

J-STAGE: View this article in J-STAGE