Method for recovering catalyst in preparation of cyclohexene by partial hydrogenation of benzene

Abstract

The invention discloses a method for recovering catalyst in preparation of cyclohexene by partial hydrogenation of benzene, comprising the following steps of: a) conveying reaction products obtained in a partial hydrogenation system of benzene into a precipitator for splitting phase so as to separate an oil phase and a water phase; b) leading the oil phase obtained by separation in the step a to enter a filter so as to separate out solids such as a catalyst and the like; c) carrying out flash vaporization on an oil-phase filtrate obtained by filtering in the step b so as to separate out a remaining gas phase; and d) carrying out washing on the oil phase flash-vaporized in the step c, extracting water-soluble substances to obtain an extracting phase, and leading the extracting phase oil phase to enter a following rectification procedure. In the catalyst recovery method, the catalyst can return to the reaction system for circular use, so that the unit consumption of the catalyst is obviously reduced, and the energy consumption can be reduced.

Description

technical field [0001] The invention relates to a catalyst recovery method, in particular to a catalyst recovery method for preparing cyclohexene by partial hydrogenation of benzene. Background technique [0002] Cyclohexene has active double bonds and is widely used as organic chemical raw materials. In particular, cyclohexene can be directly hydrated to prepare cyclohexanol, which not only shortens the production process route of caprolactam and adipic acid, but also has higher economic benefits. The current preparation methods of cyclohexene include: cyclohexanol dehydration method, halocyclohexane dehalogenation method, reduction method, etc., but these preparation methods are high in cost and very complicated in process, and cannot meet the needs of large-scale industrial production. Foreign countries have done a lot of research and experiments in exploring new processes for the preparation of cyclohexene. In 1972, American DuPont Company added additives such as water...

AI Technical Summary

Problems solved by technology

Although the phase separator and other equipment have been improved, due to the instability of the operation and the solubility of the catalyst, there are still a large number of expensive catalysts, co-catalysts and dispersants that cannot be separated from the separator and cause loss, which increases the Operating cost of the device

In addition, it is easy to cause problems such as fouling of equipment due to direct separation