The invention discloses an azeotropic rectification device and method for separating
propylene glycol monomethyl ether and water. The azeotropic rectification device and method are characterized in that
cyclohexane is adopted as an entrainer; waste liquor containing
propylene glycol monomethyl ether, water and
cyclohexane is added to a rectification kettle once; a rectification column is directly connected with the rectification kettle; a kettle-type
reboiler is arranged on the rectification kettle; the waste liquor is heated into steam through the kettle-type
reboiler and then enters the rectification column; the material at the top of the column is condensed and then transferred into the a
reflux ratio controller; if the material at the top of the column is an
azeotrope of
cyclohexane and water, the material is fed into a
phase splitting tank for
phase splitting, a water phase is extracted, and cyclohexane reflows; if the material at the top of the column is cyclohexane, recovered cyclohexane is obtained; if the material at the top of the column is a transition fraction of cyclohexane and
propylene glycol monomethyl ether, the material is extracted into a transition fraction
storage tank; if the material at the top of the column is propylene glycol monomethyl
ether, a propylene glycol monomethyl
ether product can be obtained; once materials in the kettle of the column are basically the heavy components of the waste liquor, the extracting at the top of the column is stopped, and the residual materials in the kettle are discharged from the bottom part of the rectification kettle. The device and method for separating propylene glycol monomethyl
ether and water are efficient and environment-friendly.