Patent ID: 7563919
Filing Date: 2009-07-21
Classification: C07C,Y02P

Abstract:
1. A process for the preparation of an alkanediol and a dialkyl carbonate comprising: (a) contacting an alkylene carbonate with an alkanol feedstock under transesterification conditions in a reactive distillation zone to obtain a top stream comprising dialkyl carbonate and the alkanol and a bottom stream comprising an alkanediol; (b) separating the top stream comprising dialkyl carbonate and the alkanol into an alkanol-rich stream and a dialkyl carbonate-rich stream; (c) recovering the dialkyl carbonate from the dialkyl carbonate-rich stream; and (d) recycling at least part of the alkanol-rich stream to the reactive distillation zone as part of the alkanol feedstock, wherein the alkanol-rich stream is split in at least two portions, and at least one portion is condensed and freed from compounds with a lower boiling point than the alkanol.