Continuous production device for diazotization reaction

Abstract

A continuous production device for a diazotization reaction comprises an annular tubular reactor (1), wherein the annular tubular reactor (1) is provided with a feed opening A (11), a feed opening B (12), a discharge opening C (13) and an emptying opening (14); the annular tubular reactor comprises a reaction pipeline part (15) and a communicating pipeline part (16) for communicating the upper part and the lower part of the reaction pipeline part (15); a downwardly-pressing push-type stirrer (17) is arranged inside the reaction pipeline part (15). The continuous production device for the diazotization reaction is simple in equipment arrangement, small in acid consumption, small in pollution, uniform and controllable in reaction temperature distribution, uniform in material mixing and stable and controllable in reaction staying time.

Description

technical field [0001] The invention relates to a continuous production device for diazotization reaction. Background technique [0002] The dye industry is one of the industries with the longest history in the fine chemical industry. In recent years, with the development of my country's light textile industry, the dye industry has also developed rapidly; especially since the beginning of the new century, my country's dye industry has developed more rapidly, and its output, export volume and consumption have leapt to the first place in the world. [0003] At present, in the diazonium salt synthesis method adopted by dye enterprises, batch reaction equipment is often used for batch diazotization reaction. In the diazotization reaction, diazonium salt is easy to decompose at high temperature, and the preparation of diazonium salt is An exothermic reaction, therefore, the heat transfer requirements of the production process are rather high. In a conventional batch reactor, it...

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Problems solved by technology

[0006] In the continuous production reported in the above-mentioned prior art, a large amount of sulfuric acid is used to dissolve aromatic amine materials, so that a large amount of low-concentration inorganic acids will be produced in subsequent production, and the cost of environmental protection treatment is relatively high; in addition, the uniform distribution of materials in the reaction process The degree is still unsatisfactory, and defects such as excessive local temperature will still occur, which greatly reduces the quality and yield of the product

[0007] The patent CN105367444A of Zhejiang Runtu Research Institute Co., Ltd. discloses a continuous diazotization reaction process for dyes. Although the acid used to dissolve aromatic amine materials is reduced and the amount of acid is reduced, the following defects still exist: ( 1) Multiple loop reactors connected in series are used in this process, and each loop reactor is equipped with a backflushing device, which is similar to a batch-operated reactor, and has a general effect on the mixing of materials, so there are still intermittent Some disadvantages of operation: uneven material distribution, high local temperature, etc.; (2) due to poor material mixing effect, the reaction time is prolonged, and multiple loop reactors are required to be connected in series to achieve the final reaction effect, and the equipment layout is relatively complicated; (3) This patent uses a circulation pump to realize the circulation of materials. Since part of the nitrogen oxide gas will be generated during the diazotization process, the material will generate foam, which will cause the circulation pump to produce cavitation, which will cause uneven material circulation and shorten the reaction residence time. And feed rate is difficult to stabilize

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