Process for azeotropic distillation

A process for separating a compound from a mixture of water and the compound which comprises:

• (a) distilling the mixture in a distillation column in the presence of an entrainer which forms an azeotrope with the water in an azeotropic zone of the column;
• (b) separating the azeotrope as an overhead fraction;
• (c) condensing the azeotrope to form a water-rich phase and an entrainer-rich phase;
• (d) refluxing a first portion of the entrainer-rich phase into the upper region of the azeotropic zone through a first entrainer feed and a second portion into the lower region of the azeotropic zone through a second entrainer feed;
• (e) detecting the temperature in the lower region of the azeotropic zone;
• and
• (f) controlling the amount of entrainer refluxed through the second entrainer feed based on the temperature so as to suppress a temperature change in the lower azeotropic zone.