Separation of higher-rank phenols from coal tar models: a combination of experiment and mechanism analysis

To separate higher-rank phenols from the coal tar, the model oil was constructed, and the separation efficiency of various solvents was analyzed using solvent power, selectivity, and performance index. The liquid-liquid equilibrium data of cumene + {4-ethylphenol, 4-propylphenol, 2-allylphenol, and 2-isopropylphenol} + ethanolamine was measured at 298.2 K and 101.3 kPa, and the distribution coefficient and separation factor were calculated. Furthermore, the NRTL and UNIQUAC models were correlated with the LLE data, and the model parameters were tested by the GMcal_TieLinesLL tool, which shows that the results meet the Gibbs stability criteria. The separation mechanism was explored by analyzing σ-profile, deformation charge density, interaction energy, and RDG analysis.