Bifunctional catalyst as well as preparation method, application and application method thereof

Abstract

The invention belongs to the technical field of catalysts. The invention provides a bifunctional catalyst, a series of perovskite type composite materials LaxA<1-x>FeyM<1-y>O3 are prepared by adjusting the feeding molar ratio of various metal salts, and then the bifunctional catalyst is prepared by modifying the perovskite type composite materials LaxA<1-x>FeyM<1-y>O3 with an alkali metal compound. The invention also provides a method for preparing cyclohexene by chemical looping cyclic oxidative dehydrogenation of cyclohexane, which comprises the steps of placing the prepared bifunctional catalyst in a fixed bed reactor, setting the temperature, introducing air, and activating the catalyst; introducing nitrogen to purge a reaction tube; mixing cyclohexane and nitrogen, and then introducing into the reactor to be in contact with the catalyst for an oxidative dehydrogenation reaction; and after the reaction is finished, introducing air to complete regeneration of the bifunctional catalyst. The development and application of the novel technology for efficiently preparing cyclohexene by chemical looping oxidative dehydrogenation of cyclohexane provided by the invention can effectively solve the cyclohexene production capacity bottleneck which hinders the popularization of a green process for producing caprolactam and adipic acid through a cyclohexene route.

Description

technical field [0001] The invention relates to the technical field of catalysts, in particular to a bifunctional catalyst and its preparation method, application and application method. Background technique [0002] Cyclohexene is an important organic intermediate widely used in industries such as textile, pharmaceutical, automobile, pesticide and food. It can be used as a raw material for the preparation of adipic acid, cyclohexyl formic acid, cyclohexene oxide, etc.; it is often used as an extractant and a stabilizer for high-octane gasoline in the petroleum industry. [0003] At present, there are many technical methods for producing cyclohexene in industry. Traditionally, there are methods such as dehydration of cyclohexanol and dehydrohalogenation of halocyclohexane. Due to the use of cyclohexanol, halocyclohexane and alkali metals or alkaline earth metals with high cost as raw materials, the production process is complicated and the cost is high. The liquid-phase p...

AI Technical Summary

Problems solved by technology

The method has low production efficiency and high energy consumption for separation, and uses noble metal ruthenium black catalyst and Zn salt promoter as the catalytic system

Simultaneously, in order to prevent the deactivation of the precious metal Ru catalyst, the method has strict requirements on the purity of the raw material benzene, and the production cost is high.

Although researchers at home and abroad are still working on more efficient catalytic systems for the partial hydrogenation of benzene, the contradiction between reaction conversion and cyclohexene selectivity is always difficult to resolve

Images