Recovery Of Cyclohexane From Cyclohexane Oxidation Tail Gas By Solvent Absorption Method

Cyclohexanone is a kind of important organic chemical raw material,and a kind of important intermediate for the production of adipic acid and caprolactam,it can also be used as industrial solvent,applied in paint,pesticides,dyes and other areas.Industrial production method of cyclohexanone included three methods as follows:cyclohexane oxidation method,cyclohexene hydration method and phenol method.Based on the industrial device for oxidation of cyclohexane to cyclohexanone,the recovery process of cyclohexane from the exhaust gas was studied.In depth understanding of the production process of cyclohexanone,and its process parameters and operating parameters,and through the research of using different methods for recovery of cyclohexane in the oxidation exhaust gas,the appropriate recovery method was determined,and the optimal operation parameters,the optimal process control methods were ascertained for the purpose of recycling cyclohexane from the exhaust gas.Through the research,the three-tower continuous production device was adopted,making the exhaust gas containing cyclohexane produced by air oxidation of cyclohexane go through the pipeline,and then into the absorption tower by use of the exhaust gas pressure itself,and then to the subsequent devices,the last waste gas reached drainage standard and then been discharged;One part of the cyclohexane rich absorption liquid went back to the absorption tower by pump to absorb cyclohexane of the exhaust gas,and the other part of the cyclohexane rich absorption liquid went after heat transfer into the desorption tower to be desorpt,and the top material of the desorption tower was disposed successively by condensation,water knockout process,and then was sent into the flash tower processing to obtain high purity cyclohexane,the desorption tower bottom regeneration of absorbent could return to the absorption tower for recycling use.Using solvent absorption recovery process of cyclohexane from the oxidation exhaust gas of cyclohexane can compensate for the deficiencies of low recovery rate of the original device,which exhaust the cyclohexane content to decrease from 1.8 per thousand to 0.1 per thousand,and would not cause the emissions of cyclohexanone,and while the product could be produced in more than 99% of cyclohexane purity,which can realize the recovery and recycling of raw materials.