Patent ID: 7622601
Filing Date: 2009-11-24
Classification: B01D,C07C,C08G,Y02P

Abstract:
1. In a process for the production of a high-purity diaryl carbonate in which a diaryl carbonate is produced by taking as a starting material a reaction mixture containing an alkyl aryl carbonate that has been obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound, continuously feeding the starting material into a reactive distillation column comprising a continuous multi-stage distillation column in which a homogeneous catalyst is present, carrying out a transesterification reaction and distillation simultaneously in said column, continuously withdrawing a low boiling point reaction mixture containing a produced dialkyl carbonate from an upper portion of the column in a gaseous form, and continuously withdrawing a high boiling point reaction mixture containing a diaryl carbonate from a lower portion of the column in a liquid form, wherein the improvement comprises: (a) said high boiling point reaction mixture is continuously introduced into a high boiling point material separating column A, and continuously subjected to separation by distillation into a column top component A (b) said column top component A (c) said column top component B