In this paper, the separation of toluene from aliphatic hydrocarbons (heptane, or octane, or nonane) was analyzed by solvent extraction with 1-ethyl-3-methylpyridinium ethylsulfate ionic liquid, [EMpy][ESO4]. Liquid liquid equilibrium (LLE) data for the ternary systems (heptane (1) + toluene (2) + [EMpy][ESO4] (3)}. {octane (1) + toluene (2) + [EMpy][ESO4] (3)}, and {nonane (1) + toluene (2) + [EMpy][ESO4] (3)} were obtained by measurements at T = 298.15 K and atmospheric pressure. The selectivity, % removal of aromatic, and solute distribution ratio, obtained from experimental equilibrium results, were used to determine the ability of [EMpy][ESO4] as a solvent. The degree of consistency of the experimental LLE values was ascertained using the Othmer-Tobias and Hand equations. The experimental results for the ternary systems were correlated with the NRTL model. Finally, the results obtained were compared with other ionic liquids and other solvents. (C) 2010 Elsevier Ltd. All rights reserved.