Process for the treatment of waste mother liquors from the preparation of adipic acid

摘要

Process for working up mother liquors, which were obtained in the production of adipic acid by oxidation of cyclohexanol and / or cyclohexanone or their mixtures with nitric acid, distilling nitric acid as an azeotrope with water, heating the melt obtained to 130 to 180 ° C and then in Water dissolves, the aqueous solution is treated with cation exchangers, then again water is evaporated and the dicarboxylic acid melt obtained is heated to a temperature of 200 to 240 ° C. and then a dicarboxylic acid mixture is obtained by distillation.