Patent ID: 6187972
Filing Date: 2001-02-13
Classification: C07C,Y02P

Abstract:
A process for producing an alkylene glycol, which is a continuous process for producing an alkylene glycol comprising the following steps (1) to (4), wherein the hydrolysis step (2) is divided into a plurality of stages, and the hydrolysis is carried out so that the water concentration in a reaction stage wherein the conversion of the alkylene carbonate is at least 60%, is from 15 to 30 wt %:(1) a carbonating step of reacting an alkylene oxide with carbon dioxide gas in the presence of a carbonating catalyst to form a reaction solution containing an alkylene carbonate,(2) a hydrolysis step of hydrolyzing the reaction solution obtained in step (1) while releasing carbon dioxide gas, to form an aqueous alkylene glycol solution,(3) a distillation step of distilling the aqueous alkylene glycol solution to obtain at least a dehydrated alkylene glycol and a solution containing the carbonating catalyst, and(4) a recycling step of supplying the solution containing the carbonating catalyst to the carbonating step (1).