环己烷氧化物水洗液氧化制精己二酸的工艺研究

Preparation of purified adipic acid by oxidation of washing liquid of cyclohexane oxides

采用氧化-萃取-结晶-重结晶的方法,将环己烷氧化液酸洗水浓缩液进行氧化,再萃取出影响已二酸结晶的物质,结晶分离出粗己二酸,再对粗己二酸进行重结品,干燥得到精己二酸。结果表明:以氧化剂A和H_2O_2为氧化剂,氧化时间2h,氧化温度65℃,氧化液用萃取剂进行萃取,萃取后的水相在30℃结晶2h,再在35℃下重结晶,得到的己二酸纯度达到99.8%,收率约40%,熔点151.41℃。

Using oxidation-extraction-crystallization-recrystallization method, the condensed acidic washing liquid of cyclohexane oxidation was oxidized, from which the compounds that hindered the crystallization of adipic acid were extracted so as to separate crude adipic acid by crystallization. Purified adipic aicd was prepared from the crude adipic acid by recrystallization and drying. The results showed that the purity of adipic acid was 99.8%, the yield about 40% and the melting point 151.41℃ when the mixture of oxidant A and H2O2 was used as an oxidant system, the oxidation time 2 h, oxidation temperature 65℃, crystallization time 2 h at 30℃ and recrystallization temperature 35℃ for the extracted aqueous phase.