Preparation method of cyclohexanone-oxime

Abstract

The invention provides a preparation method of cyclohexanone-oxime, which is implemented in a way that: under reaction conditions of cyclohexanone ammoximation, a reaction raw material containing cyclohexanone, ammonia, hydrogen peroxide and solvent passes through a plurality of catalyst bed layers in a fixed-bed reactor; each catalyst bed layer contains a titanium-silicon molecular sieve and resin; the titanium-silicon molecular sieve contains a Ti-MWW-F molecular sieve; in the flow direction of the reaction raw material in the reactor, the resin content in the catalyst bed layer increases progressively; and the weight percent of at least part of resin in the catalyst bed layer is less than 50%. The preparation method provided by the invention can obtain higher cyclohexanone conversion rate and cyclohexanone-oxime selectivity.

Description

technical field [0001] The invention relates to a preparation method of cyclohexanone oxime. Background technique [0002] Cyclohexanone oxime is a key intermediate for the synthesis of caprolactam and an important chemical raw material, mainly used as a raw material for the preparation of nylon 6 monomer for fiber nylon 6 and engineering plastics. [0003] Since titanium-silicon molecular sieve catalysts play a very important role in the selective oxidation of organic compounds, as a preparation method for cyclohexanone oxime, it has been proposed to use hydrogen peroxide and ammonia to react cyclohexanone oxime in the presence of titanium-silicon molecular sieve catalysts. A method for ammoximation of ketones. The advantage of this method is that it does not need to use ammonia to neutralize sulfuric acid like the previous method of oximation with hydroxylamine sulfate. [0004] In the process of cyclohexanone ammoximation to prepare cyclohexanone oxime, titanium-silicon...

AI Technical Summary

Problems solved by technology

However, there are following problems in these processes using shaped titanium-silicon molecular sieves: the formation of titanium-silicon molecular sieves and the use of binders in the molding process not only cause the loss of titanium-silicon molecular sieves, but also affect the pore volume and specific surface area of ​​the catalyst. influences

Yet, in the actual production process according to the method for this patent application, because resin content is too high (usually 50-99 weight %) in the catalyst bed layer, make the conversion rate of cyclohexanone and cyclohexanone in the ammoximation process of cyclohexanone Ketoximes are less selective

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