Liquid-Liquid Equilibria of the Water+1-Propanol+1-Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide Ternary System: Study of the Ability of Ionic Liquid as a Solvent

An important problem in the chemical industry is the separation of azeotropes. Their separation by simple distillation is basically impossible, and extractive distillation consumes much more energy than liquid liquid extraction, so this alternative could be interesting. Recently, researchers have started to explore these option using ionic liquids as the solvent. The remarkable properties of ionic liquids have made them sustainable alternatives to conventional solvents. This work is a continuation of a study developed by our research group on the use of ionic liquids as extractant solvents of alcohol + water mixtures which form azeotropes, using in this case 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide abmp][Tf2N]) as an ionic liquid. The effect of temperature on the liquid-liquid equilibrium for the water + 1-propanol + [bmp] [Tf2N] system was studied by determining the tie lines at different temperatures (283.2, 303.2, and 323.2 K) and atmospheric pressure: The NRTL and UNIQUAC models were successfully used to correlate the experimental data. Finally, the distribution coefficient and selectivity were calculated to evaluate the ability of this ionic liquid as an extracting solvent.