A kind of preparation method of catalyst for synthesizing hexamethylene diamine by hydrogenation of adiponitrile

Abstract

The invention discloses a preparation method of a catalyst for synthesizing hexanediamine by carrying out hydrogenation on hexane dinitrile. The catalyst is an amorphous state nickel alloy catalyst, and is prepared by the method comprising the steps of (1) preparation of catalyst powder: firstly, preparing ammonia water and nickel nitrate into nickel-ammonium complex solution, mixing the nickel-ammonium complex solution with modifying agent water solution, stirring, carrying out hydrothermal aging, filtering separation and drying calcination on the mixture, filling hydrogen, and reducing at high temperature to obtain the catalyst powder; (2) activation of the catalyst: slowly feeding the catalyst powder into NaOH solution, heating and stirring for a certain period of time under the condition of microwave; after the reaction is completed, removing the upper-layer alkali liquor, washing the product to be neutral with deionized water, and washing with absolute ethyl alcohol for later use. The activity of the obtained amorphous state nickel alloy catalyst is evaluated by the conventional reaction conditions. The catalyst is uniform in distribution of active components, and the conversion rate of the hexane dinitrile and the selectivity of the hexanediamine are higher.

Description

technical field [0001] The invention belongs to the technical field of petrochemical catalysis, and in particular relates to a method for preparing a catalyst for hydrogenating adiponitrile to synthesize hexamethylenediamine, in particular to a method for preparing an amorphous nickel alloy catalyst. Background technique [0002] Raney catalyst is a widely used reduction catalyst, mainly used in the catalytic hydrogenation of organic compounds. According to the different metal active centers, there are Raney iron, Raney cobalt, Raney nickel, etc. Among them, the Raney nickel catalyst with nickel as the active center is the most widely used. For example, hexamethylenediamine is used as a monomer for the production of nylon-66. At present, adiponitrile is mainly used as a raw material, and Raney nickel catalyst is used to prepare it in a tank reactor or a fluidized bed reactor. At present, the main problems of this catalyst are low activity and selectivity, large amount of ca...

AI Technical Summary

Problems solved by technology

At present, the main problems of this catalyst are low activity and selectivity, large amount of catalyst, serious environmental pollution, etc. Therefore, it is necessary to develop new and more efficient catalyst materials to improve the yield of hexamethylenediamine products and achieve atom economy.

[0003] At present, there are mainly the following methods for modifying the Raney catalyst: one is to add a modifier to melt during the preparation of the parent alloy, and then crush and activate it, such as the amorphous prepared by Chinese invention patents 01134263.3, 02150722.8 and 201210212109.2 State alloy catalyst, its shortcoming is high temperature melting preparation alloy consumes a lot of energy; the second is that after the modifier is added in the preparation process, the catalyst is modified by means of ultrasonic treatment, such as Chinese invention patent 201310467071.8, etc., its shortcoming lies in the simple use The performance improvement of ultrasonic treatment catalyst is small; the third is to use the impregnation method to modify the prepared catalyst, such as Japanese patent 03249946A and Chinese invention patent 97102713.7, etc. The uniformity of the catalyst prepared by this method is poor