Ternary liquid–liquid equilibria of bis(trifluoromethylsulfonyl)-amide based ionic liquids + methanol + heptane

Ternary liquid–liquid equilibria for 3 systems containing ionic liquids (4-(2-methoxyethyl)-4-methylmorpholinium bis(trifluoromethylsulfonyl)-amide, 1-(2-methoxyethyl)-1-methylpiperidinium bis(trifluoromethylsulfonyl)-amide, 1-(2-methoxyethyl)-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)-amide) + methanol + heptane have been determined at T = 298.15 K. All systems show total miscibility of methanol in the ionic liquid and low solubility of heptane. The solute distribution ratio and the selectivity were calculated for all systems. High selectivities and solute distribution ratios were obtained for all systems. The experimental results have been correlated using NRTL model.

► Ternary liquid–liquid equilibria for [NTf2]− anion based ionic liquid + methanol + heptane.
► The influence of ionic liquid cation structure on phase diagrams is discussed.
► High selectivity for separation of heptane/methanol is observed.