The phenols recovery process is a significant part of treating coal chemical wastewater with highly concentrated phenols and ammonia. Solvent extraction is an important unit for phenol recovery section. The accurate measurement of liquid-liquid equilibrium (LLE) data is essential for realizing partitioning. In this paper, the LLE data for the ternary system water + 2-, 3-, 4-methylphenol +3,3-dimethyl-2-butanone (also known as methyl tert-butyl ketone, MTBK) were studied at the temperatures of 333.2 K and 353.2 K under 101.3 kPa. The extraction performance of MTBK was estimated by partition coefficients and separation factors. The extraction efficiencies of MTBK were compared with those of MIBK, mesityl oxide, and those results of MTBK at five different temperatures from 298.2 K to 353.2 K were also contrasted with each other. In addition, the nonrandom two-liquid (NRTL) and universal quasi chemical (UNIQUAC) models were applied to fit the measured LLE data. The results indicate that the calculated data based on the NRTL and UNIQUAC equations are good as reported by the experimental data, and the root-mean-square error (RMSE) values are lower than 2.50%. The obtained binary interaction parameters in this study can be used in the calculation of the LLE about the ternary system (water + 2-, 3-, 4-methylphenol + MTBK) as well as for the design and optimization of industrial process to remove methylphenols from effluents.