| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for preparing 1,6-hexanediol from a carboxylic acid mixture. <P>SOLUTION: The method for preparing 1,6-hexanediol includes processes of: (a) converting carboxylic acids contained in an aqueous dicarboxylic acid mixture to the corresponding carboxylic acid esters by using a low-molecular weight alcohol; (b) separating the obtained esterification mixture from excessive alcohol and low-boiling point components in a first distillation stage; (c) fractionating bottom products in a second distillation stage into an ester fraction essentially free of 1,4-cyclohexanediol and a fraction comprising the major part of 1,4-cyclohexanediol; (d) catalytically hydrogenating the ester fraction essentially free of 1,4-cyclohexanediol; and (e) obtaining 1,6-hexanediol in a purifying distillation stage from the hydrogenation product in a known manner. In this way, high purity 1,6-hexanediol can be obtained in a high yield from waste products. <P>COPYRIGHT: (C)2013,JPO&INPIT |
