Method and device for producing o-chloroaniline without solvent

Abstract

The invention discloses a method and a device for producing o-chloroaniline without a solvent. The method utilizes o-chloronitrobenzene as a raw material, a dechlorination inhibitor as an assistant 1, ammonia water as an assistant 2 and a platinum-carbon catalyst. At a hydrogenation liquid pH of 6-8, under the pressure of 0.5-0.9Mpa, at a temperature of 85-105 DEG C, hydrogen is fed into a reactor and the reaction system undergoes a continuous reaction in the reactor; then the hydrogenation liquid is collected in a hydrogenation liquid tank by a catalyst filter; the catalyst filtered by the catalyst filter is blown back into the reactor by the catalyst filter for recycle; and the hydrogenation liquid subjected to water separation is fed into a rectification system and then is rectified so that a qualified product is obtained. The method and the device have the advantages of simple processes, low production cost, high automation degree, high yield, high output, high reaction selectivity, good product quality, mild reaction conditions, good safety, low labor intensity, no pollution, and easy popularization.

Description

technical field [0001] The invention belongs to the field of chemical production, and relates to a method and a device for producing o-chloroaniline without solvent. Background technique [0002] At present, iron powder reduction method and hydrogenation reduction method are commonly used in the production of o-chloroaniline. Among them, the iron powder method has been gradually eliminated due to serious environmental pollution. Although the hydrogenation reduction method is more advanced, it needs to use methanol as a solvent. Need to add nitro substances dropwise, not only the output of single kettle is low, but also the reaction end point is difficult to judge, in addition, in the process of separating the solvent, some methanol enters the waste water, causing environmental pollution and increasing product cost. The reaction pressure required for production is as high as 1.0MPa or more, and the operation is dangerous and the safety risk is great. Contents of the inventi...

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Problems solved by technology

[0002] At present, iron powder reduction method and hydrogenation reduction method are commonly used in the production of o-chloroaniline. Among them, the iron powder method has been gradually eliminated due to serious environmental pollution. Although the hydrogenation reduction method is more advanced, it needs to use methanol as a solvent. Nitro compounds need to be added dropwise, not only the output of the single pot is low, but also the reaction end point is difficult to judge. In addition, during the process of separating the solvent, some methanol enters the waste water, causing environmental pollution and increasing product costs.

The reaction pressure required for production is as high as 1.0MPa or more, the operation is dangerous and the safety risk is great

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