从己二酸副产物中分离提纯戊二酸

Separation and purification of glutaric acid from by-product in production of adipic acid

采用结晶、成盐和酸化法对己二酸装置的副产物混合二羧酸进行分离提纯,可以得到高纯度的戊二酸。结果表明,当混合二羧酸/水(质量比)不小于3.0∶1.0时,戊二酸的相对质量分数保持在80%以上,分离效果较为理想。根据丁二酸、己二酸和戊二酸与氧化镁反应生成盐的溶解度不同,可以进一步脱除丁二酸和己二酸。成品戊二酸的质量分数为99.83%,丁二酸和己二酸均小于0.20%。

The mixed dicarboxylic acid, by - prod- uct in production of adipic acid,was separated and purified by crystallization, salt formation and acidification,and then the high purity glutaric acid was obtained. The results showed that the mass fraction of glutaric acid was above 80% and the separation effect was better when mole ratio of mixed dicarboxylic acid to water was no less than 3.0： 1.0. Based on the different solubility of the salts formed from the reactions between succinic acid, glutaric acid and adipic acid with magnesium oxide,the succinic acid and adipic acid were removed further,the mass fraction of final product glutaric acid was 99.83% ,succinic acid and adipic acid were less than 0. 20%.