Liquid–liquid equilibria for the extraction of phenols from alkane using ethylene glycol

The separation of low temperature coal tar can be carried out using extraction technology, especially for the collection of phenols. Liquid–liquid equilibria data for the ternary mixture of 1-Heptane + phenols + ethylene glycol were obtained at 323.15 K and 343.15 K under atmospheric pressure, where phenols refer to phenol, o-cresol, m-cresol and p-cresol. The tie lines were displayed in ternary phase diagrams. The distribution coefficient and selectivity were calculated according to the measured tie-line data. The calculation results revealed that the selectivity was large enough for the extraction application. The root-mean-square deviation (RMSD) value of the NRTL model was a little lower than that of UNIQUAC, demonstrating NRTL can better fit the experimental data.