Isobaric vapor liquid equilibrium measurements of the ethanol/water binary mixture and ethanol/water/ionic liquid ternary mixtures were performed using an ebuliometer at 101.3 and 66.6 kPa. The ionic liquids (ILs) synthesized and examined as entrainers for the ethanol/water azeotropic mixture were 1-butyl-3-methylimidazolium bromide ([BMIM][Br]) and 1-ethyl-3-methylimidazolium bromide ([EMIM][Br]). For both ILs, the initial concentrations for the ternary mixtures were 5%, 10% and 15% w/w. The entrainers were also tested for their recoverability and biodegradability. Analysis with H-1 NMR proved that the ionic liquids can be recycled and reused while their ability to biodegrade was found to be relatively low. Introduction: of the entrainers to the ethanol/water system resulted in an increase of the relative volatility, due to the salting-out effect on ethanol, leading to the successful elimination of the azeotropic point. The effect on the relative volatility follows the order [EMIMI[Br] > [BMIMI[Br], which corresponds to the order of increasing affinity of water to the specific entrainers. Finally, the thermodynamic modeling of the ethanol/water/IL mixtures was investigated with the UNI-QUAC and NRTL models. The results for both models were found to be in good agreement with the experimental data. (C) 2014 Elsevier B.V. All rights reserved.