PROCESS FOR THE PREPARATION OF DIARYL CARBONATES OR ARYLALKYL CARBONATES FROM DIALKYL CARBONATES

摘要

A method for manufacturing diaryl carbonates or arylalkyl carbonates from dialkyl carbonates is provided to improve the energy integration remarkably. A method for manufacturing at least one diaryl carbonate or alkylaryl carbonate or their mixture from at least one dialkyl carbonate(1) and at least one aliphatic hydroxy compound(2) comprises: (i) a step for reacting dialkyl carbonates with aliphatic hydroxy compounds, in the presence of at least one transesterification columns (K1) containing at least one reaction zones, under a concentration part having at least one concentration part(VT1, VT2) and at least two sections at the top of column; (ii) a step for condensing the steam vapor removed from a head of a transesterification column in at least one condenser completely and partly; and (iii) returning the condensation heat obtained from an intercondenser to the process directly or indirectly.