AZEOTROPIC DISTILLATION PROCESS

摘要

A process of azeotropic distillation which comprises the following steps (1) to (5): step (1): a step of azeotropically distilling a solution to be distilled containing water, an aliphatic carboxylic acid and an aliphatic carboxylate using an entrainer to give an aliphatic carboxylic acid having a reduced water content and an overhead fraction having a concentrated water content, step (2): a step of condensing the overhead fraction to give a gas and a liquid condensate being separated into a water phase and an oil phase, step (3): a step of withdrawing the water phase and the oil phase of the condensate separately, step (4): a step of distilling a part or all of the water phase thus withdrawn to give an overhead fraction containing the above aliphatic carboxylate and having a reduced water content, and step (5): a step of distilling the overhead fraction in step (4) together with a part or all of the oil phase in step (3) to give a fraction containing the above aliphatic carboxylate and recovering a part or all of the aliphatic carboxylate fraction to the outside of the azeotropic distillation system.