A method for reducing hydrogenation of nitro groups to amino groups in a high-gravity reactor

Abstract

The invention discloses a method for reducing nitryl into amidogen in a high-gravity reactor by hydrogenation. The method comprises the following steps: selecting the high-gravity reactor, and switching on a motor of the high-gravity reactor to drive a speed increasing gear to rotate so as to drive a stirring wing in a material feeding cavity to rotate at an ultrahigh speed; putting hydrogen and anitryl-containing organic compound into the material feeding cavity for gas-liquid two-phase efficient mixing to disperse insoluble hydrogen into a large amount of nano-micron bubbles in the organiccompound, and forming a gas-liquid mixture when the solubility of the hydrogen in the organic compound is oversaturated; conveying the gas-liquid mixture into the high-gravity reactor through a liquiddistributor, and carrying out a gas-liquid-solid catalytic hydrogenation reaction process on the surface of metal catalyst-loaded structured packing. The reactor used in the method enables the liquidphase solubility of the insoluble hydrogen to be oversaturated; the reducing hydrogen is efficiently used, and gas-liquid-solid mass transferring is enhanced.

Description

technical field [0001] The invention belongs to the field of catalytic hydrogenation reaction in fine chemical industry, and in particular relates to a method for reducing hydrogenation of nitro group to amino group in a supergravity reactor. Background technique [0002] Compounds containing amino groups are important organic raw materials in the chemical industry. The main way to generate amino groups is to selectively hydrogenate and reduce the nitro groups in the compounds. The generated amino compounds are widely used in fine chemicals such as dyes and pesticides, and Explosives and other military fields. For example, aniline is an important organic raw material and one of the most important aromatic amines. It is widely used in polyurethane, rubber additives, medicine and other industries. Most of the rubber additives are based on aniline. The commonly used industrial production process is: adopting catalytic hydrogenation method to reduce nitro group to amino group. ...

AI Technical Summary

Problems solved by technology

However, the fixed bed has problems such as large pressure drop, uneven bed temperature distribution, complex structure and serious catalyst wear in the fluidized bed. It is difficult to control the catalytic hydrogenation reaction process well, which in turn affects the catalytic effect. There are problems such as large floor area and high industrial energy consumption

[0004] In recent years, many important progresses have been made in the application research of high gravity technology in the chemical industry. CN103102942A successfully passed the raw material oil into the high gravity reactor equipped with non-precious metal catalyst, and contacted with hydrogen countercurrently to perform desulfurization, denitrogenation and partial aromatic hydrocarbon saturation reaction , but adopt the mode of packing catalyst, the operation process is difficult, the pressure drop in the reaction process is relatively large, and the catalyst is easily deactivated; CN104419454A fixes the metal-polymer catalyst on the rotor of the high-gravity rotating bed reactor, and pyrolysis gasoline and hydrogen pass through the rotating However, the above invention still has the problem of low solubility of hydrogen in the raw material, and the contact area between the solid catalyst and the liquid raw material containing dissolved hydrogen has not been effectively increased, which restricts the reaction of the hydrogenation process. Further improvements in efficiency and product yield

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