Method for producing adipic acid by utilizing air oxidation of cyclohexane based on gas-liquid-solid heterogeneous reaction separation synchronous reactor

Abstract

The invention discloses a method for producing adipic acid by oxidizing cyclohexane by utilizing air based on a gas-liquid-solid multiphase reaction and separation synchronization reactor. The method is characterized by adding cyclohexane to the gas-liquid-solid multiphase reaction and separation synchronization reactor, wherein the reactor comprises a reaction tower and at least two constant temperature settling towers communicated with the bottom of the reaction tower, and the reaction tower is internally provided with a gas phase zone, an oxidation zone and a gas outlet; during reaction, filling the oxidation zone and constant temperature settling towers with cyclohexane, continuously pumping air from the bottom of the oxidation zone to come into contact with cyclohexane to carry out oxidation reaction, simultaneously enabling generated adipic acid solid to enter the constant temperature settling towers through settling, at the moment, enabling cyclohexane in the constant temperature settling towers to enter the oxidation zone via an external circulation system so that reaction is continuously carried out, enabling adipic acid to continuously settle in the constant temperature settling towers until the constant temperature settling towers are filled with the adipic acid phase, and switching a reaction tower to be communicated with the other constant temperature settling tower filled with cyclohexane, thus alternating the steps to carry out continuous production. The method can be used for continuously producing adipic acid with high conversion rate and high yield, and has the effects of improving the production efficiency and reducing the production cost.

Description

technical field [0001] The invention relates to a process for producing adipic acid by oxidizing cyclohexane with air. Background technique [0002] Adipic acid is the basic chemical raw material of Nylon 66. Industrially, the liquid-phase nitric acid oxidation of cyclohexanone is the main method for preparing adipic acid. The process of preparing adipic acid from cyclohexanone with nitric acid uses high-cost cyclohexanone as a raw material, and nitric acid will corrode equipment and have problems of environmental pollution. In recent years, some patents have disclosed the process of preparing adipic acid through the biomimetic catalytic air oxidation of cyclohexane by metalloporphyrins. Patent CN1850756A and patent CN1530358A disclose the process and equipment for the preparation of adipic acid by low-concentration metalloporphyrin biomimetic catalytic air oxidation of cyclohexane, but the product obtained by this technology is a mixture of cyclohexanol, cyclohexanone and...

AI Technical Summary

Problems solved by technology

The continuous process of insoluble products can be realized by adding solvents; however, the addition of solvents makes the chemical production process complicated, and also increases the corresponding equipment investment and energy consumption, material consumption and environmental pollution by solvents; another One option is to use interstitial operations to produce

In the above two schemes, the residence time of the reaction product in the reaction system will be increased, and under the reaction operating conditions, the reaction product will be decomposed or deeply reacted, resulting in a decrease in the selectivity and yield of the reaction product

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