| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a dialkyl carbonate and a diol from a cyclic carbonate and an aliphatic monohydric alcohol and enabling the increase of the production of the highly demanded diol with a simple apparatus by adjusting the production ratio of the products. SOLUTION: A dialkyl carbonate and a diol are produced by reacting raw materials in the presence of a catalyst in a continuous multistage distillation column A. A mixture containing the dialkyl carbonate is extracted from the top of the column A and a mixture containing the diol is extracted from the bottom of the column A. The mixture containing the diol is supplied to another distillation column B, compounds having boiling points lower than that of the diol are returned to the column A and a mixture containing the diol as a main component is obtained from the bottom of the column B. In the above process, (a) the conversion of the cyclic alkylene carbonate is 10-95%, (b) the diol-containing mixture extracted from the bottom of the column A is brought into contact with water before supplying the mixture to the column B, and (c) the water concentration in the compounds having boiling point lower than that of the diol and returned from the column B to the column A is≤5,000 ppm. COPYRIGHT: (C)2006,JPO&NCIPI
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