Experiments and COSMO-SAC Modeling of Methyl Isobutyl Ketone + Dimethylphenols + Water Mixtures

Abstract

Methyl isobutyl ketone (MIBK) had been successfully employed to extract phenols from coal gasification wastewater since 2009, and it has been proved to be an excellent extraction solvent. In this work, the liquid–liquid equilibrium (LLE) data were measured for the ternary systems MIBK + 2,3-/3,4-/3,5-dimethylphenol + water from 298.15 to 343.15 K. High partition coefficient and separation factor indicated that MIBK could extract dimethylphenols from an aqueous solution well. The Hand equation and the Bachman equation were used for testing the consistency of the determined tie-line data. The NRTL and UNIQUAC thermodynamic models were utilized to correlate these measured LLE data, and their root-mean-square deviations did not exceed 0.5%. The conductor-like screening model for segment activity coefficient was employed to predict the LLE data. Results showed that the prediction values are close to the measured data.