Process for the preparation of diaryl carbonates or arylalkyl carbonates from dialkyl carbonates

Abstract

The invention provides a process for the preparation of diaryl carbonates and/or alkylaryl carbonates from dialkyl carbonates and aromatic hydroxy compounds using one or more intermediate condensers for improving heat integration.

1 .- 13 . (canceled) 
     
     
         14 . A column for the reaction of dialkyl carbonates with aromatic hydroxy compounds in the presence of at least one transesterification catalyst for the preparation of diaryl carbonates and/or alkylaryl carbonates, comprising
 at least one inlet for the dialkyl carbonate(s) and at least one inlet for the hydroxy compound(s),   at least one outlet for the gaseous head product in the upper portion of the column and at least one outlet for the liquid sump product in the lower portion of the column,   at least one concentrating part in the upper portion of the column and at least one reaction zone beneath a concentrating part, which has at least two sections,   wherein at least one concentrating part is equipped with at least one intermediate condenser.   
     
     
         15 . The column according to  claim 14 , wherein the column has at least one stripping part beneath a reaction zone. 
     
     
         16 . The column according to  claim 14 , wherein the concentrating part, which is equipped with at least one intermediate condenser, is divided into a lower and an upper concentrating part, of which the lower concentrating part is located beneath the intermediate condenser and the upper concentrating part is located above the intermediate condenser. 
     
     
         17 . The column according to  claim 14 , wherein the intermediate condenser and optionally the upper concentrating part are integrated in the column or are in the form of a separate device outside the column. 
     
     
         18 . The column according to  claim 14 , wherein the reaction zone of the transesterfication column has 3 to 50 theorectical plates. 
     
     
         19 . The column according to  claim 14 , wherein the reaction zone of the transesterfication column has 10 to 40 theorectical plates.