Safe and environment-friendly aromatic amine production system and process

Abstract

The invention discloses a safe and environment-friendly aromatic amine production system, which comprises a nitrification system, a washing system, a hydrodesolvation system and a dehydration and deaniline system. The nitrification system comprises a microchannel nitrifier, an acid separator and a vacuum concentration system, and the washing system comprises a washing tower and a sewage treatmentsystem; the hydrodesolvation system comprises a hydrogenation system and a desolvation tower, and the dehydration and deaniline system comprises a dehydration tower, a deaniline tower and a rectification system. The production process comprises the following steps: (1) continuous nitrification; (2) continuous washing; (3) hydrodesolvation; (4) dehydration and deaniline. The safe and environment-friendly aromatic amine production system and process disclosed by the invention have the advantages of simple technological process, safe, environment-friendly and reliable operation, low energy consumption, low equipment investment, simple operation, reduction in amount of a nitrifying material, improvement on safety of the nitrification system, elimination of a pot type concentration system withserious environmental pollution, reduction in investment and operating cost, good washing effect, low sewage treatment capacity, and reduction in production cost.

Description

technical field [0001] The invention belongs to the technical field of production of phenylenediamine and aniline, and specifically relates to a production system and process of a safe and environment-friendly aromatic amine. Background technique [0002] Aromatic amine refers to an amine with an aromatic substituent. Aromatic amine is a liquid with a high boiling point or a solid with a low melting point. Resin can also be used as a rubber vulcanization accelerator, etc. It can be used as a black dye itself. Phenylenediamine is one of the simplest aromatic diamines, and it is also a widely used intermediate, which can be used to prepare azo Dyes and high molecular polymers can also be used to produce fur dyes, rubber anti-aging machines and photo developers. [0003] In the prior art, benzene, 98%-105% sulfuric acid and nitric acid are used as raw materials, which are nitrated to generate mixed dinitrobenzene, which are hydrogenated and reduced to mixed diamine, and then r...

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Problems solved by technology

[0003] In the prior art, benzene, 98%-105% sulfuric acid and nitric acid are used as raw materials, which are nitrated to generate mixed dinitrobenzene, which are hydrogenated and reduced to mixed diamine, and then rectified to generate m-phenylenediamine, O-phenylenediamine and p-phenylenediamine products, in which about 68% of the dilute sulfuric acid produced by nitration is vacuum compressed into about 88%-92% of sulfuric acid, and then concentrated in a pot to form more than 98% of sulfuric acid. A pre-washing, alkali washing and water washing system composed of a stirring nitration machine, but the safety of this method is poor, the temperature in the nitration kettle is unstable, the flash point of nitrobenzene is 87.7°C, and the conditions such as high temperature, static electricity and air exist at the same time. Explosion occurs, the reaction temperature is not well controlled, the nitration conditions are harsh, the production cost is high, and a large amount of alcohol solvent is used in the hydrogenation process, generally exceeding 40-60%, resulting in a large amount of desolvation, high energy consumption and washing Large power consumption, large consumption of washing water and alkali, and a lot of sewage, which increases the amount of sewage treatment

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