Experimental study on (vapor + liquid) equilibria of ternary systems of hydrocarbons/ionic liquid using headspace gas chromatography

(Vapor + liquid) equilibrium (VLE) data for ternary systems of (hexane + benzene), (hexane + cyclohexane), (benzene + cyclohexane), (1-hexene + cyclohexane), and (1-hexene + benzene) with an ionic liquid were measured by headspace gas chromatography. The applied ionic liquid 1-methyl 3-octylimidazolium thiocyanate, [Omim][SCN], acts as an entrainer. The comparison of the measured VLE data with the equilibrium data for the binary mixtures without ionic liquid show that [Omim][SCN] significantly improves the separation factor of these systems. The NRTL thermodynamic model is applied for correlating the experimental data. The modeling results show the NRTL model can correlate the experimental data with a good accuracy.

► The ionic liquid [Omim][SCN] is considered as an appropriate entrainer for separation of five binary hydrocarbon systems.
► VLE data for the ternary systems consisting [Omim][SCN] and hydrocarbons were measured using headspace gas chromatography.
► The experimental VLE data are correlated using the thermodynamic model of NRTL with a good accuracy.
► The experimental results are compared with the VLE data using other ionic liquids as the entrainer.
► [Omim][SCN] can significantly improve the separation factors of these systems.