To further reduce the total phenols of coal-gasification wastewater which comes from the Lurgi pressurized coal-gasification process, methyl isobutyl ketone (MIBK) instead of diisopropyl ether (DIPE) is used as the extraction solvent in the process to remove the phenols. To obtain process parameters for an industrial trial, process simulations with a treatment capacity of 100 ton/h wastewater are carried out. The simulation results show that with the use of MIBK as an extraction solvent, the total phenol concentration of coal-gasification wastewater can be reduced from 5410 ppm to less than 200 ppm. The operation cost estimate shows that using MIBK as an extraction solvent to extract and remove phenols from coal-gasification wastewater has good economic feasibility. With the process parameters obtained from the simulation, an industrial trial is implemented and satisfactory agreement is found. With the total phenol concentration reduced to below 200 ppm in the pretreatment, the coal-gasification wastewater can be decontaminated in the subsequent biological treatment.