Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Ionic liquids (ILs) as replacements of organic solvents currently used in the liquid liquid extraction of aromatics could simplify extraction units as a result of their nonvolatile nature, reducing operating costs, and process steps. In this paper, we have studied the liquid liquid extraction of toluene from n-hexane, n-octane, and n-nonane using binary mixtures of 1-ethyl-4-methylpyridinium bis(trifluoromethylsulfonyl)imide ([4empy][Tf2N]) and 1-ethyl-3-methylimidazolium dicyanamide ([emim][DCA]) ILs at 313.2 K. Toluene distribution ratios and toluene/n-alkane selectivities employing the IL mixtures have been intermediate between those of pure ILs. The {[4empy][Tf2N] + [emim][DCA]} IL mixture with a [4empy][Tf2N] mole fraction of 0.3 has exhibited higher extractive properties than the sulfolane values. Toluene distribution ratios and toluene/n-alkane selectivities of the mixed ILs have been accurately predicted by the Yalkowsky and Roseman log linear mixing rule. Liquid liquid equilibria (LLE) data have been correlated to the NRTL model.