Method for preparing catalyst for preparing secondary amines by hydrogenation of nitrile compounds, catalyst product and application of catalyst product

Abstract

The invention provides a method for preparing a catalyst for preparing secondary amines by liquid-phase catalytic hydrogenation of nitrile compounds, a catalyst product obtained by the method and an application of the catalyst product. The catalyst consists of 0.1-10 wt% of an active component Pd, 0.1-80 wt% of an auxiliary agent, Ni or an oxide of Ni, on the basis of Ni metal element, and the balance of a carrier. The method comprises supporting the active component and the auxiliary agent onto the carrier by an impregnation method, a coprecipitation method, a chemical vapor deposition method, an atomic layer deposition method or any combination of the methods so as to obtain the catalyst. The catalyst obtained by the method provided by the invention can be used to realize catalytic hydrogenation of different nitriles to prepare corresponding secondary amines under mild reaction conditions, wherein the preparation is high in conversion rate and selectivity; the catalyst has high stability and can be repeatedly used for a plurality of times; and in addition, the reaction has obvious advantages of less wastewater discharge, low toxicity and the like.

Description

technical field [0001] The invention relates to a preparation method of a catalyst used for liquid-phase catalytic hydrogenation of nitrile compounds to prepare secondary amines, and the obtained catalyst product and application. Background technique [0002] Secondary amine is an important fine chemical and organic synthesis intermediate, which has a very wide and large number of applications in dyestuff, pesticide, pharmaceutical, rubber and other industries. Taking the dibenzylamine involved in the present invention as an example, dibenzylamine is a special raw material for synthesizing efficient and nontoxic rubber vulcanization accelerator tetrabenzylthiuram disulfide (TBZTD) and zinc dibenzyldithiocarbamate (ZBEC) , It can also be used for the synthesis of penicillin, and the determination of cobalt, iron and cyanate. With the improvement of domestic rubber industry standards, the demand for replacing traditional additives with green additives TBZTD and ZBEC that do n...

AI Technical Summary

Problems solved by technology

These methods are simple and reliable, but have many obvious disadvantages: one, often obtain the mixture of primary, secondary, and tertiary amines, and the product needs additional purification, which not only increases the cost but also causes waste of raw materials; two, A large amount of halogen-containing wastewater will be produced during the ammonification of haloalkane. Not only the equipment is seriously corroded, but also the product contains impurity halogens and the quality is poor; 3. There is no obvious economic advantage in using primary amines, primary alcohols or aldehydes as upstream raw materials

At present, it is rare to realize the efficient and selective hydrogenation of nitriles to secondary amines by combining Pd noble metals and Ni transition metals and utilizing their dual-functional synergistic effects.

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