Method for producing crotonic acid by catalytic oxidation method

Abstract

The invention discloses a method for producing crotonic acid by a catalytic oxidation method, which comprises the following steps: by using crotonaldehyde as a raw material and cerium-zirconium composite oxide as a catalytic oxidant, weighing the crotonaldehyde and the cerium-zirconium composite oxide in a weight ratio of 1: (0.1-1.1), and adding the crotonaldehyde and the cerium-zirconium composite oxide into a solvent to obtain a mixed solution; uniformly mixing the mixed solution to enable the cerium-zirconium composite oxide to be uniformly dispersed in the mixed solution; carrying out catalytic oxidation reaction under the conditions that the reaction temperature is 70-90 DEG C and the pressure is 0.1 -0.5 MPa to obtain a crotonic acid crude product; evaporating the crotonic acid crude product to recover unconverted crotonaldehyde, and filtering to obtain a crotonic acid crude product filtrate; cooling, crystallizing, filtering and drying the crude crotonic acid filtrate to obtain crotonic acid; and carrying out high-temperature calcination and oxygen enrichment treatment on the recovered catalytic oxidant, and then recycling. The method provides a new idea for the production of crotonic acid, improves the conversion rate of crotonaldehyde, simplifies the subsequent treatment process, and reduces the production cost.

Description

technical field [0001] The invention relates to the technical field of production of crotonic acid, in particular to a method for producing crotonic acid by a catalytic oxidation method. Background technique [0002] Crotonic acid, also known as crotonic acid, its chemical structure is CH 3 CH=CHCOOH. It is an unsaturated fatty acid with double bonds and carboxyl groups in its molecule, which has strong reactivity and has a wide range of uses in industry. It is mainly used to prepare various resins, fungicides, surface coatings, fungicides, and plasticizers. It can also be used as important pharmaceutical intermediates, pesticide intermediates and other organic chemical intermediates. In industrial production, it is mostly prepared by catalytic oxidation of crotonaldehyde. [0003] The basic principle of preparing crotonic acid by oxidation of crotonaldehyde is as follows: [0004] 2CH 3 CH=CHCHO + O 2 → 2CH 3 CH=CHCOOH. [0005] During the reaction, crotonaldehyde i...

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Problems solved by technology

[0009] Although, through the use of precious metals, silver nitrate and multi-component catalysts, the reaction speed has been accelerated, the reaction time has been shortened, and the yield of products per unit time has been improved, but because the catalysts used contain more expensive precious metal components The use cost of the catalyst is higher, which ultimately increases the production cost of crotonic acid; and the reaction conditions in the catalytic reaction process are harsh, and the post-treatment process is also relatively complicated, which is not conducive to its large-scale industrial production; in addition, because the catalyst material itself Due to the reason of strength, a small part of metal impurities is easy to be produced in the production process, which will affect the quality of crotonic acid finished products