Ethylene glycol and 1,2-butylene glycol separation method

The present invention relates to a method for separating ethylene glycol and 1,2-butanediol, addressing the presence of high energy separation problems of the prior art. By using the present invention comprises the following steps: a) the crude product into the column glycol, 1,2-butanediol and ethylene glycol to obtain an overhead azeotrope, the column reactor to obtain ethylene glycol; B) 1,2-D diol and ethylene glycol azeotrope into the azeotropic distillation tower, an azeotropic agent is added to an azeotropic distillation column from the top of the column to give an overhead entrainer azeotrope with ethylene glycol, 1,2-tower reactor to obtain butanediol product; c) ethylene glycol and entrainer azeotrope was condensed into the phase separator, is divided into an upper stream rich in azeotropic agent and a lower stream rich in ethylene glycol; upper azeotropic distillation stream is returned column overhead; D) into the lower stream entrainer recovery column, the overhead stream is recycled to the azeotropic distillation column, bottoms product stream is recycled to the column aspect solves the problem, and can be used to separate ethylene glycol industrial production of 1,2-butanediol.