Liquid-liquid equilibrium (LLE) data for the ternary systems methylcyclohexane + benzene + 1-ethyl-3-methylpyridinium ethylsulfate, methylcyclohexane + toluene + 1-ethyl-3-methylpyridinium ethylsulfate, and methylcyclohexane + ethylbenzene + 1-ethyl-3-methylpyridinium ethylsulfate are reported under atmospheric pressure and at T = 298.15 K. The selectivity, the percent removal of aromatic compound, and the distribution coefficient were calculated from the LLE data, and the influence of the presence of radicals in the benzene ring were analyzed. The reliability of the experimental LLE data was ascertained using the Othmer-Tobias and Hand equations. The nonrandom two-liquid (NRTL) model was used to correlate the experimental data for the ternary systems. A search of the literature has indicated that data for the mixtures presented here have not been reported previously.