Method for treating organic pollutants by using chitosan modified active coke to support nano-gold catalyst in situ

Abstract

The invention discloses a method for treating organic pollutants by utilizing a chitosan-modified activated coke in-situ supported nanogold catalyst. The method adopts the chitosan-modified activatedcoke in-situ supported nanogold catalyst to catalytically treat organic pollutants, wherein the chitosan-modified activated coke in-situ supported nanogold catalyst comprises activated coke, chitosanand nanogold particles, the surface of the activated coke is modified by the chitosan, so that a chitosan / activated coke compound is formed, and the nanogold particles are loaded on the chitosan / activated coke compound. In the invention, by adopting the chitosan-modified activated coke in-situ supported nanogold catalyst to catalytically treat organic pollutants, the organic pollutants can be quickly and thoroughly catalytically reduced within a short time, and thereby the organic pollutants are effectively degraded. The method disclosed by the invention has the advantages of simple process, easiness in operation, low treatment cost, high treatment efficiency, good treatment effect and the like, and has high application value and a wide application range.

Description

technical field [0001] The invention belongs to the technical field of nano metal catalyst preparation, and relates to a method for treating organic pollutants by using chitosan-modified active coke to support nano-gold catalyst in situ. [0002] technical background [0003] Nitroaromatic compounds are a class of toxic and biodegradable organic pollutants, and are important raw materials and intermediate products in chemical production. With the development of the chemical industry, nitroaromatic compounds also enter the environment through various channels, polluting the environment and endangering human health. At the same time, aminophenol, the reduction product of nitroaromatic compounds, is an important chemical and pharmaceutical intermediate used in the synthesis of dyes, medicines, synthetic resins, surfactants and other chemical products. Azo dyes are compounds containing one or more azo bonds, are highly toxic and resistant to biodegradation, and are also an organ...

AI Technical Summary

Problems solved by technology

Although the supported nano-gold catalyst with low toxicity and high specific surface area can catalyze the oxidation of CO and electrochemical reduction of CO at low temperature 2 , Catalytic reduction of nitroaromatics and other aspects have caused many scholars to study. However, in the existing supported nano-gold catalysts, the effect of reduction treatment of nitroaromatic compounds and azo dyes is not good, and the catalytic efficiency is not ideal.

In addition, carbon materials such as carbon nanotubes, carbon nanofibers, graphene (graphene oxide), and mesoporous carbon are often used as carrier materials for nano-gold, but these carrier materials have high cost, low mechanical strength, and underdeveloped pore structure. and other problems, and the acquisition methods of these carbon materials are relatively complicated and difficult to obtain. At the same time, due to the chemical inertness of these carbon materials, the interaction with nano-gold is weak, which makes it challenging to load nano-gold. For example, nano-gold is easy Therefore, whether the binding force between nano-gold and carbon support can be further enhanced is one of the concerns of current supported nano-gold catalysts.

The existing preparation methods of supported nano-gold catalysts include impregnation method, deposition-precipitation method, co-precipitation method, chemical vapor deposition method, etc. These methods have the following disadvantages: incomplete loading of nano-gold catalysts, poor repeatability of the preparation process, and extremely susceptible to solvents. Influenced by the oxidation effect and the cluster effect of metal components, resulting in poor dispersion of gold nanoparticles, unstable catalyst structure (poor stability), high amount of precious metals, and the addition of chemical reagents such as sodium borohydride and hydrazine during the preparation process, while These chemical reagents will cause secondary pollution to the environment and do not meet the theme of green chemistry

In addition, the existing deposition-precipitation method, impregnation method and other methods are difficult to achieve high dispersion of gold nanoparticles on carbon support materials.

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