Method for separating impurities in crude maltol product

The invention relates to a method for separating impurities in a crude maltol product. The method comprises the steps as follows: a, a hydrolyzed material is filtered and cooled to 30-35 DEG C; b, a hydrolysate is pumped into an extraction mixer, and meanwhile, chloroform is pumped, so that the hydrolysate and chloroform are fully mixed; c, a mixed solution enters a layering device, a layered light phase enters a hydrolysate collecting tank, a lower heavy phase enters a chloroform collecting tank and placed in a distillation still for recovering of chloroform by distillation, and the distilledmaterial is sent to a sublimation kettle for sublimation; d, the light phase material in the hydrolysate collecting tank is pumped into a neutralization kettle, the PH is adjusted to 2.5-3.5, the temperature is decreased to 40-45 DEG C, the material is placed in a crystallizer for freezing crystallization, and the crystallized material is sent to the sublimation kettle for sublimation after centrifuge dripping. The metho