Preparation method of aza-carbon-coated cobalt catalyst and unsaturated compound catalytic transfer hydrogenation method based on catalyst

Abstract

The invention discloses a preparation method of an aza-carbon-coated cobalt catalyst. The preparation method comprises the following steps of uniformly mixing a carbon source, a nitrogen source, a cobalt salt and a solvent according to a mass ratio of x to (6-x) to (1 to 6) to (1 to 10), wherein x is an integer of 0 to 6; drying an obtained mixture, and roasting the mixture in a vacuum tubular furnace in inert gas; acidifying the roasted mixture in diluted acid, separating solid and liquid, and washing and drying the solid, so as to obtain the aza-carbon-coated cobalt catalyst. The invention also discloses a method using the catalyst prepared by the method for the catalytic transfer hydrogenation of unsaturated compounds, especially vanilline, benzaldehyde, cinnamyl aldehyde or quinoline. The preparation method has the advantages that the preparation method is simple, the cost of the raw materials is low, and the obtaining is easy; cobalt is coated into aza-carbon, so that while the high activity is maintained, the acid-resistant property and anti-CO (carbon monoxide) toxicity property of the catalyst are improved; formic acid is used as a hydrogen source to replace high-pressure hydrogen in a catalytic reduction reaction of the unsaturated compounds, the environment-friendly and economic effects are realized, the selectivity of a target product is high, and the generation of byproducts is avoided.

Description

technical field [0001] The invention relates to a composite material catalyst, in particular to a preparation method of an azacarbon-coated cobalt catalyst and a method for catalytic transfer hydrogenation of an unsaturated compound based on the catalyst. Background technique [0002] The rapid economic development is accompanied by a large amount of energy consumption, and the stock of traditional renewable energy is gradually becoming scarce. Finding renewable energy is one of the important issues for the sustainable development of human society. Biomass oil is a mixture of various degradation products of cellulose, hemicellulose and lignin, which contains a large number of unsaturated compounds such as aldehydes, aromatic rings, ketones, phenols, etc., the highest oxygen content It can be as much as half, and too high oxygen content will easily lead to poor chemical stability and low calorific value of the oil, which is extremely unfavorable for its application. Commonly...

AI Technical Summary

Problems solved by technology

[0003] The existing unsaturated compound catalytic hydrogenation reaction conditions are relatively harsh, high temperature, high hydrogen pressure to be used, and high catalyst cost, all of which affect the utilization of biomass oil to a certain extent

For example, the Chinese patent with the application number 201410280751.3 discloses a method entitled "a method for preparing a carbon-nitrogen material-supported nano-metal catalyst", which mainly uses a carbon-nitrogen material-supported nano-metal catalyst, and the supported nano-precious metals are rhodium, ruthenium, Iridium, the catalyst can catalyze amine compounds, the selectivity is high, and the catalyst can be recycled many times, but the active center is more expensive to use noble metals, and the production cost is high

The Chinese patent with the application number 201610566647.X discloses a method entitled "a carbon-nitrogen material-supported cobalt catalyst and a method for synthesizing a pipemaserin intermediate", which mainly combines metal cobalt compounds and cyano-containing ionic liquids It is coordinated in an organic solvent and impregnated onto a carrier, and then calcined at a specific temperature under an inert gas to obtain a catalyst supported by a corresponding carbon-nitrogen material. When the catalyst is used in the synthesis of a pipemaserin intermediate, the 1. In the presence of 1-methyl-4-piperidone, use a carbon-nitrogen supported cobalt catalyst, hydrogen as a reducing agent, toluene or xylene as a solvent, and react at 130-150°C with a hydrogen pressure of 2-3Mpa for 18 ~24h; or the temperature is 110~120℃ and the hydrogen pressure of 0.5~1Mpa can be reacted for 18~24h. Although the catalyst has high activity and good selectivity, it needs to use hydrogen when it is used for the catalytic reaction of unsaturated compounds, and the reaction time is relatively long. long

Images