PROCESS FOR PREPARING DIARYL CARBONATE AND POLYCARBONATE

摘要

PROBLEM TO BE SOLVED: To provide processes for continuously preparing a diaryl carbonate from phosgene in the presence of a catalyst and to provide a method for using the processes for the preparation of a polycarbonate.SOLUTION: There is provided a process for preparing a diaryl carbonate which comprises: (a) a step of preparing phosgene by the reaction between chlorine and carbon monoxide; (b) a step of forming a diaryl carbonate and hydrogen chloride by reacting the phosgene formed in the step (a) and monophenol; (c) a step of isolating and finishing the diaryl carbonate formed in the step (b); (d) a step of isolating and refining when required the hydrogen chloride formed in the step (b); (e) a step of thermally oxidizing at least a part of the hydrogen chloride from the step (d) into oxygen and chlorine to form water; and (f) a step of recirculating at least a part of the chlorine prepared in the step (e) for the preparation of phosgene in the step (a).SELECTED DRAWING: Figure 1