Journal of Chemical Thermodynamics, Vol.118, 92-99, 2018
Study of liquid-liquid extraction of ethanol plus water azeotropic mixtures using two imidazolium-based ionic liquids
The present work was focused on the study of two imidazolium-based ionic liquids (ILs) as solvents in liquid-liquid extraction of ethanol from aqueous mixtures. With this aim, the experimental liquid-liquid equilibria (LLE) data of water (1) + ethanol (2) + 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfo nyl) imide ([emim][Tf2N]) (3) and water (1) + ethanol (2) + 1-hexyl-3-methylimidazolium bis(trifluorome thylsulfonyl) imide ([hmim][Tf2N]) (4) systems were obtained at different temperatures: 283.2, 303.2, and 323.2 K, in order to check the influence of temperature. The results were correlated by nonrandom two-liquid (NRTL) and universal quasichemical (UNIQUAC) models with good concordance in both cases. Finally, the ability of the two ILs to act as solvents was studied by evaluating the coefficient distribution and the selectivity of ternary systems and compared with another IL from the literature. (C) 2017 Elsevier Ltd.
Keywords:Liquid-liquid extraction;Ionic liquid;1-Ethyl-3-methylimidazolium bis(trifluoro methylsulfonyl)imide ([emim][[Tf2N]);1-Hexyl-3-methylimidazolium bis(trifluoro methylsulfonyl)imide ([hmim][[Tf2N]);Ethanol;Water