Application of the ionic liquid tributylmethylammonium bis(trifluoromethylsulfonyl)imide as solvent for the extraction of benzene from octane and decane at T = 298.15 K and atmospheric pressure

•The ionic liquid N4441NTf2 was evaluated as solvent to extract benzene from alkanes.•The quaternary system {octane + decane + benzene + N4441NTf2}.•Selectivity and solute distribution ratio were calculated and compared.•The comparison of results for ternary and quaternary systems has been performed.•Experimental data were satisfactorily correlated using NRTL model.

In this work, the ionic liquid tributylmethylammonium bis(trifluoromethylsulfonyl)imide, [N4441][NTf2], has been evaluated as potential extraction solvent for the separation of benzene from its mixtures with octane and decane. The liquid–liquid equilibrium (LLE) data for the ternary systems {octane (1) + benzene (2) + [N4441][NTf2] (3)} and {decane (1) + benzene (2) + [N4441][NTf2] (3)} and for the quaternary system {octane (1) + decane (2) + benzene (3) + [N4441][NTf2] (4)} were determined at T = 298.15 K and atmospheric pressure. Solute distribution ratios and selectivities were calculated from the experimental LLE data and analyzed in order to evaluate the suitability of the ionic liquid in the studied separation. Finally, experimental results for the ternary and quaternary systems were correlated with the Non-Random Two-Liquid (NRTL) thermodynamic model.