Preparation method and application of composite nano nickel catalyst

Abstract

The invention discloses a preparation method of a composite nano nickel catalyst. The preparation method comprises the steps of: preparing amorphous-state nickel with small nanoscale and highly dispersed active components by using a chemical reduction method in the presence of ludox as soft load material; reducing and depositing crystalline-state nano nickel on a carrier by using the amorphous-state nickel as an inductive agent; and adjusting the proportion of amorphous-state nickel and crystalline-state nickel to prepare the ludox loaded composite nano nickel catalyst. Compared with an industrial Raney Ni catalyst and single amorphous-state nickel or crystalline-state nickel, the composite catalyst shows excellent catalysis performance in hydrogenation reaction of 4-chloro-2-nitrophenol for preparing 4-chloro-2-amino phenol.

Description

technical field [0001] The invention relates to a new method for preparing composite nano-nickel catalyst. Using silica sol as the loading material, the composite nano-nickel catalyst in amorphous and crystalline states was prepared by combining the chemical reduction method and the electroless plating method. The catalyst exhibits excellent catalytic performance in the hydrogenation reaction of 4-chloro-2-nitrophenol to 4-chloro-2-aminophenol. Background technique [0002] 4-Chloro-2-aminophenol is an important intermediate in the production of dyes, mainly used in the preparation of acid medium RH, acid complex violet 5RN and reactive dyes, and can also be used in the preparation of raw material chlorzoxazone. Its traditional production process mainly adopts iron powder reduction method, but this method produces a large amount of iron sludge, which causes serious pollution to the environment. Although the Raney Ni catalyst has great advantages such as high activity, good...

AI Technical Summary

Problems solved by technology

Its traditional production process mainly adopts iron powder reduction method, but this method produces a large amount of iron sludge, which causes serious pollution to the environment

Although the Raney Ni catalyst has great advantages such as high activity, good sedimentation separation and low price for this reaction, the Raney Ni catalyst itself also has many serious disadvantages.

For example, the intermediate frequency electric furnace heating used in the melting process causes huge power consumption; a large amount of waste alkaline water pollutes the environment during the activation process, and is accompanied by a large loss of Al resources

These "structural defects" bring a heavy burden to industrial applications, especially the outstanding safety of Raney Ni catalyst, making it a "target" of many catalytic workers

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