A device and method for removing impurities from circulating tert-butanol in a cyclohexanone ammoximation process

Abstract

The invention discloses a device and method for circulating tertiary butanol impurity removal in a cyclohexanone ammoximation technology. The device comprises a circulating tertiary butanol storage tank and a tertiary butanol refining tower, the top of the tertiary butanol refining tower is sequentially connected with a condenser, a reflux tank and a reflux pump, the reflux pump is connected to the tertiary butanol refining tower and a newly-made circulating tertiary butanol storage tank through a pipeline, and the bottom of the tertiary butanol refining tower is connected to a wastewater treatment unit through a discharging pump at the bottom of the tower. By the adoption of the device, the water content in circulating tertiary butanol can be effectively reduced, the concentration of circulating tertiary butanol is increased to 80-85% from 72-75% before refining, the feeding load of a reaction kettle is reduced, and the reaction environment is improved; refining and impurity removing are performed on circulating tertiary butanol, the content of impurities of a reaction system is reduced, a lot of side reactions are avoided, and reaction selectivity is improved.

Description

technical field [0001] The invention belongs to the field of chemical technology and equipment, in particular to a device and method for removing impurities from circulating tert-butanol in a cyclohexanone ammoximation process. Background technique [0002] Cyclohexanone oxime is an important intermediate in the production of caprolactam. The main production method of cyclohexanone ammoximation is to use hydrogen peroxide, ammonia and cyclohexanone to react in the presence of titanium silicon molecular sieve catalyst and tert-butanol solvent. Cyclohexanone oxime, through the filtration system, filters out the molecular sieve catalyst to obtain the reaction liquid, and then recovers tert-butanol and extracts and rectifies to obtain high-purity cyclohexanone oxime. [0003] In the existing cyclohexanone ammoximation process, tert-butanol is recovered through a tert-butanol recovery tower in the tert-butanol recovery process, and the recovered tert-butanol is returned to the ox...

AI Technical Summary

Problems solved by technology

This increases the difficulty of purification of raw materials such as cyclohexanone and hydrogen peroxide on the one hand, and also increases the consumption of hydrogen peroxide and gaseous ammonia on the other hand.

In addition, due to the tert-butanol-water azeotrope, the water content in the top of the tert-butanol recovery tower is high under high load, resulting in an increase in the proportion of water in the circulating tert-butanol, and this part of water increases the load of the reactor after being introduced into the reactor , and the larger the proportion of water in the system, the more unfavorable the oximation reaction

[0004] Therefore, it is necessary to seek a method for removing impurities in a cyclohexanone ammoximation device, and the existing cyclohexanone ammoximation device and method do not involve the device and method for recycling tert-butanol.

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