Ternary (liquid–liquid) equilibria of nitrate based ionic liquid + alkane + benzene at 298.15 K: Experiments and correlation

Liquid–liquid equilibria (LLE) were determined for the ternary systems of ionic liquid + alkane (hexane, heptane or octane) + benzene at T = 298.15 K and atmospheric pressure. 1-Butyl 3-methylimidazolium nitrate [Bmim][NO3] or 1-methyl 3-octylimidazolium nitrate [Omim][NO3] were used as ionic liquid. The selectivities values for the ternary systems with [Bmim][NO3] are higher than [Omim][NO3]. The selectivities values show that [Bmim][NO3] is more suitable solvent for benzene extraction than [Omim][NO3]. The reliability of the LLE data was tested using Othmer–Tobias and Hand equations. The experimental data was correlated using the NRTL thermodynamic model. The results show the NRTL model can correlate the experimental data with good accuracy.

► The extraction of benzene from hexane, heptane or octane was studied using ionic liquid. ► The ionic liquids [Bmim][NO3] and [Omim][NO3] were used. ► The selectivities values for the ternary systems with [Bmim][NO3] are higher than [Omim][NO3]. ► [Bmim][NO3] is more suitable solvent for extraction of benzene than [Omim][NO3]. ► The NRTL model were used for correlation of the experimental data.