Regeneration method for nickel-base hydrogenation catalyst

Abstract

The invention relates to the regeneration method for a nickel hydrogenation catalyst, which is divided into two stages: aminolysis of the condensation polymer, with catalyst bed temperature being 120-180deg.C, ammonia pressure being 0. 1-0. 5MPa, dimension ratio of ammonia and the catalyst being 10-40, regenerated time being 1-2 hours, hydrogenation for aminolysis in the temperature of 150-280deg.C, hydrogen pressure 1. 0- 3. 0MPa, hydrogen and catalyst dimension ratio being 10-40, regeneration time being 2-10 hours. Its activeness can reach the level of fresh catalyst. Due to tempered regeneration conditions, it can extend the life of the catalyst significantly.

Description

technical field [0001] The invention relates to a catalyst regeneration method, in particular to a regeneration method for preparing m-xylylenediamine-containing nickel granular catalyst through hydrogenation of isophthalonitrile. Background technique [0002] M-xylylenediamine is mainly used in epoxy resin curing agent and nylon modified polymer monomer. Usually m-xylylenediamine is produced by hydrogenation of isophthalonitrile. The hydrogenation reaction can adopt tank-type intermittent hydrogenation or fixed-bed continuous hydrogenation process, and the catalysts are all fine-grained catalysts or granular fixed-bed catalysts with nickel as the active component. From the comparison of hydrogenation effect, product quality and production cost, it can be seen that the batch hydrogenation process is obviously inferior to the continuous process in terms of product yield, production cost and product quality, making the process of producing m-xylylenediamine by fixed bed hydro...

AI Technical Summary

Problems solved by technology

[0006] Among the above technical solutions, some are only applicable to the regeneration of fine-grained Raney nickel-type catalysts, and cannot be used for the regeneration of fixed-bed nickel-containing catalysts

However, in the existing technical solution for the regeneration of the fixed-bed nickel-containing catalyst, since the regeneration temperature is as high as 200-500°C, although the polycondensate covering the catalyst surface can be hydrogenated at this time, the nickel atoms on the catalyst surface will also be hydrogenated at the same time. The growth of cluster grains reduces the activity of the catalyst. In addition, because the hydrogen needs to be heated to such a high temperature, it not only increases the equipment investment, but also increases the energy consumption.

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