Method for separating and purifying m-cresol from mixture of m-cresol and p-cresol

The invention relates to a method for separating and purifying m-cresol from a mixture of m-cresol and p-cresol by using a complex crystallization method. The method comprises the following steps: 1) complex crystallization: adding a mixture of m-cresol and p-cresol into a reactor, adding urea and heating to 70-95 DEG C to completely dissolve the urea in the mixture of m-cresol and p-cresol; cooling, adding petroleum ether when the mixture is cooled 50-60 DEG C, wherein the adding amount of petroleum ether is 1-2 times the volume of the raw material of the mixture of m-cresol and p-cresol, and crystallizing at 0 DEG C-8 DEG C for 2-4 h; 2) solid-liquid separation washing to obtain white needlelike m-cresol complex crystals and a filtrate 1; 3) decomplexation: pumping the complex crystal and adding of toluene, decomplexing at 50-60 DEG C under the, and filtering while hot to obtain a solid urea and a filtrate 2, wherein the filtrate 2 is a mixture of m-cresol and toluene; and 4) distillation: separating m-cres