Trickle bed equipment for preparing m-Metaxylenediamine

Abstract

The invention discloses trickle bed equipment for preparing m-Metaxylenediamine. A trickle bed is provided with a material inlet which is connected with a gas and liquid mixer for mixing gas and liquid materials and conveying the mixed materials to the material inlet; the gas and liquid mixer comprises a container shell; a bottom plate of the container shell is provided with a plurality of gas inlets; each gas inlet is connected with a vertical short pipe extending into the container; each vertical short pipe is provided with a plurality of gas outlets; the upper end of the container shell isprovided with a liquid inlet; and the side face of the container shell is provided with a material outlet connected with the material inlet of the trickle bed. The gas and liquid can be fully mixed before entering a distributor, so the gas and liquid distribution condition in the trickle bed is improved, overlarge radial temperature difference and local overheat of the trickle bed are avoided, polymeric by-products are reduced, the service life of a catalyst is prolonged, the hydrogenation temperature and pressure are reduced, and the molar yield of the m-Metaxylenediamine is improved.

Description

Technical field: [0001] The invention relates to a trickle bed device for preparing m-xylylenediamine. Background technique: [0002] Meta-xylylenediamine, the English name is meta-phenyldimethylamine or meta-Xylylenediamine, [0003] Molecular formula C 8 h 12 N 2 , molecular weight 136.1, CA registration number 1477-55-0, structural formula: [0004] [0005] Colorless liquid with almond smell, yellow when exposed to air for a long time, soluble in water and organic solvents, boiling point 248 degrees Celsius, specific gravity (d 20 )1.052, refractive index (nD 20 ) 1.5670, the viscosity is similar to that of dibutyl phthalate, and it is a colorless transparent liquid. [0006] It is mainly used to manufacture heat-resistant, non-toxic, underwater construction, and high-performance epoxy resin curing agent that can be quickly cured by heating. It is the raw material for polyurethane resin and synthetic functional epoxy resin. It is also used in rubber products, ph...

AI Technical Summary

Problems solved by technology

[0016] 2. In the absence of excessive hydrogen protection, the imine intermediates on the catalyst are not easy to continue hydrogenation to generate m-xylylenediamine, but will polymerize with m-xylylenediamine or other intermediates to form high Boiling impurities

[0018] 4. If the particle size of the catalyst is too small, the pressure drop of the bed layer will be too large, which is not conducive to the smooth flow of gas and liquid; if the particle size is too large, the internal diffusion effect will also lead to the generation of polymerized high boiling substances in the catalyst pores, thus Deactivate the catalyst or increase the bed pressure drop

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