Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Low transition temperature mixtures (LTTMs) are versatile alternatives to ILs. It shares many properties with ILs, which make them suitable to be used as entrainers for extractive distillation. In this study, glycolic acid and choline chloride in 3:1 molar ratio (GC3:1) was synthesized and evaluated as entrainer for separation of acetonitrile + water azeotropic mixture. Isobaric vapor-liquid equilibrium (VLE) data for the pseudo-binary mixtures of ACN + GC3:1 and water + GC3:1 was measured at atmospheric pressure (101.32 kPa). VLE data for the pseudo-ternary system ACN + water + GC3:1 was also measured at different LTTM molar fraction of 0.05, 0.1 and 0.15. The experimental data for these systems have been correlated by nonrandom two-liquid (NRTL) model. The Predicted values for these systems were found to be in good agreement with the experimental data. From the results, the azeotrope is eliminated using GC3:1 by the means of improving their relative volatility. Hence, GC3:1 is an effective entrainer for separating the acetonitrile + water binary azeotropic system. Furthermore, GC3:1 synthesized in this study was also investigated for its recoverability. 1. INTRODUCTION Acetonitrile (ACN), an important organic solvent, is widely used in many fields such as pharmaceuticals,1 liquid chromatography,2 organic synthesis,3 and photosensitive material.4 In chemical industries, there are several processes which produce mixtures of acetonitrile and water. Inhalation of higher concentrations of acetonitrile causes irritation of mucous membranes and can lead to many other health related problems.5 Acetonitrile induces toxic effects similar to that observed in acute cyanide poisoning; although, it shows some-what delayed symptoms compared to inorganic cyanides or many other saturated nitriles. It may enter in the environment through process plants effluent, municipal wastewater treatment plant's discharges or spills.