Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The objective of this work was to explore the feasibility of extraction of hex-1-ene from hexane and cyclohexene from cyclohexane with different ionic liquids (ILs). The liquid-liquid equilibrium (LLE) was studied in various binary and ternary mixtures of {IL (1) + hex-1-ene (2) + hexane (3)} and {IL (1) + cyclohexene (2) + cyclohexane (3)} at T = 298.15 K and p = 0.1 MPa. The ILs studied are as follows: 1-butyl-3-methylimidazolium dicyanamide, [BMIM][DCA], 1-butyl-3-methylimidazolium tricyanomethanide, [BMIM][TCM] and 1-butyl-4-cyanopyridinium bis{(trifluoromethyl)sulfonyl}imide, [BCN4PY][NTf2]. The results, obtained by us from the limiting activity coefficients results showed the excellent selectivity by using the ILs with (CN) groups and large solute distribution ratio by using the bis{(trifluoromethyl)sulfonyl}imide-based ILs. The chromatography analysis results indicated that the ILs used as a separation solvents were not present in the hydrocarbon-rich layer, which is convenient, because this eliminates the step needed for the separation of the solvent. The results showed that [BMIM][DCA] revealed large selectivity of extraction and acceptable solute distribution ratio in separation of hex-1-ene/hexane and cyclohexene/cyclohexane compounds. The NRTL activity coefficient model was used to correlate the LLE results.