Brief description of glutaric acid, succinic acid and adipic acid, from a mixture containing the acid thus, said acids obtained by this

摘要

A method for obtaining glutaric acid, succinic acid, and adipic acid from an acid mixture obtained as a by-product in the industry and comprising glutaric acid, succinic acid and adipic acid, which comprises the steps of: (1) contacting the acid mixture with urea of 1 to 2 moles per mole of the acid mixture, in solution, to deposit a urea- glutaric acid adduct so that the weight ratio of glutaric acid remaining in the solution to succinic acid is 1.2 or less when the adipic acid content is in the range of 0% by weight to 7% by weight and 1.4 or less when the adipic acid content is larger than 7% by weight and 30% by weight or less; separating the deposited urea-glutaric acid adduct out of the solution; (2) adding further urea to the solution and/or concentrating the solution obtained in the step (1) to deposit a urea- succinic acid adduct; separating the deposited urea-succinic acid adduct out of the solution; and (3) decomposing the separated urea-dicarboxylic acid adducts each into respective dicarboxylic acids and urea. With this method, the mixture comprising glutaric acid, succinic acid and adipic acid can, for the first time, be successfully and effectively separated into the respective components.