Determination and correlation of (liquid + liquid) equilibria of ternary and quaternary systems with octane, decane, benzene and [BMpyr][DCA] at T = 298.15 K and atmospheric pressure

•The ionic liquid BMpyrDCA was studied as solvents to extract aromatics from alkanes.•(Liquid + liquid) equilibrium data were measured at T = 298.15 K for quaternary system and ternary systems.•Selectivity and solute distribution ratio were calculated and compared.•The comparison of results obtained on LLE data of ternary and quaternary systems was analyzed.•Experimental data were satisfactorily correlated using NRTL model.

The suitability of the ionic liquid 1-butyl-1-methylpyrrolidinium dicyanamide, [BMpyr][DCA], as extraction solvent of benzene from its mixtures with octane and decane has been analyzed. (Liquid + liquid) equilibrium (LLE) data for the quaternary system {octane (1) + decane (2) + benzene (3) + [BMpyr][DCA] (4)} and for the ternary systems {octane (1) + benzene (2) + [BMpyr][DCA] (3)} and {decane (1) + benzene (2) + [BMpyr][DCA] (3)} were determined at T = 298.15 K and atmospheric pressure. Solute distribution ratios and selectivities were calculated from the experimental LLE data in order to evaluate the capability of [BMpyr][DCA] as extraction solvent. Finally, experimental results for the ternary and quaternary systems were correlated using the Non-Random Two-Liquid (NRTL) thermodynamic model.