PROCESS FOR PREPARING ALKANEDIOL AND DIALKYL CARBONATE

摘要

The invention relates to a process for the preparation of an alkanediol and a dialkyl carbonate comprising: (a) reacting an alkylene carbonate and an alkanol at a temperature of from 10 to 200 °C, at a pressure of from 5x104 to 5x106 N/m2 and in the absence of a transesterification catalyst, to obtain a mixture comprising hydroxyalkyl alkyl carbonate, alkanol and alkylene carbonate; (b) contacting the mixture comprising hydroxyalkyl alkyl carbonate, alkanol and alkylene carbonate with a transesterification catalyst at a temperature of from 10 to 200 °C and at a pressure of from 5xl04 to 5xl06 N/m2, to obtain a mixture comprising the alkanediol and the dialkyl carbonate; and (c) recovering the alkanediol and the dialkyl carbonate from the mixture comprising the alkanediol and the dialkyl carbonate.