Separation of phenol from aqueous solution by 2-octanone: Phase equilibrium measurements and thermodynamic studies

Abstract

The applicability of 2-octanone as solvent for the liquid phase extraction of phenol from aqueous solution was investigated in this work. The liquid liquid equilibrium (LLE) for the ternary systems {2-octanone + phenol + water} was experimentally determined at 298.15 K, 318.15 K and 338.15 K under atmospheric pressure. Distribution coefficients and separate factors calculated from the experimental LLE data were used to judge if 2-octanone can be used as potential solvent to extract phenol from aqueous solution. Distribution coefficients and separation factors of 2-octanone were also compared with other extractants and results show that 2-octanone has excellent extraction performance. Binary interaction parameters were regressed by the NRTL and UNIQUAC methods, and related physical meaning is explained by interaction forces. The root mean squared deviations (RMSDs) show that both models can well describe phase equilibrium behavior of ternary system {2-octanone + phenol + water}. In order to predict ternary LLE data at other temperatures, the NRTL model was used to simultaneously regress ternary experimental data at all temperatures and the largest RMSD is 0.49%.