| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for continuously and simultaneously producing a dialkyl carbonate and a glycol with low energy. SOLUTION: This method for continuously and simultaneously producing the dialkyl carbonate and the glycol comprises conducting transesterification reaction of an alkylene carbonate with an alcohol, wherein processes (a) to (d) are continuously conducted as follows: (a) the alkylene carbonate and the alcohol in an amount of less than 2 mol per mol of the alkylene carbonate are continuously fed into a fixed bed flow-through type reactor packed with a heterogeneous catalyst so as to conduct the transesterification reaction; (b) a discharged liquid from the reactor is supplied to a distillation column so as to be separated into a low-boiling fraction containing the alcohol and the dialkyl carbonate and a high-boiling fraction containing the glycol and the alkylene carbonate; (c) the dialkyl carbonate is separated and taken out from the low-boiling fraction, and simultaneously an azeotropic mixture of the alcohol and the dialkyl carbonate is returned to the reactor in the process (a); and (d) an azeotropic mixture of the glycol and the alkyl carbonate of which the main component is the glycol is separated and taken out from the high-boiling fraction, and simultaneously the alkylene carbonate is returned to the reactor in the process (a).
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