Preparation method of molecular sieve surface organic alkali etching and Pt-loaded catalyst

Abstract

The invention provides a preparation method of a molecular sieve surface organic alkali etching and Pt-loaded catalyst. The Pt / molecular sieve catalyst is prepared by taking cheap ZSM-5 and other molecular sieves and a small amount of chloroplatinic acid as raw materials, firstly carrying out silicon dissolving etching treatment on the surfaces of the molecular sieves by using an organic alkali solution, and then loading Pt by adopting an ethylene glycol liquid phase reduction method. A proper amount of organic alkali is used for carrying out silicon dissolving etching treatment on the surfaces of the molecular sieves, so that a rich hierarchical pore structure is formed on the basis of not damaging a molecular sieve skeleton, dispersion and stabilization of Pt nanoparticles are facilitated, and the mass transfer properties of macromolecular reactants and products are improved. Besides, through the catalytic synergistic effect between rich acid sites on the surfaces of the molecular sieves and oxidation centers of high-dispersion Pt nanoparticles, the low-temperature oxidation performance of the catalyst on various VOCs pollutants can be remarkably improved, and the complete oxidation temperatures (when the conversion rate is 99%) of benzene and ethyl acetate are only 130 DEG C and 190 DEG C respectively. The Pt / molecular sieve catalyst is especially suitable for low-temperature catalytic combustion of industrially discharged chlorine-containing VOCs such as dichloroethane and non-chlorine-containing VOCs such as benzene and ethyl acetate, and has a good application prospect.

Description

technical field [0001] The invention relates to a method for preparing a catalyst, in particular to a method for preparing a molecular sieve surface by etching an organic base and supporting a Pt catalyst. Background technique [0002] Volatile organic compounds (VOCs) mainly come from waste gas emissions from industries such as petrochemical production, printing and coating, food and rubber production. They are often complex in composition and large in exhaust volume, and pose serious hazards to the natural environment and human health. Catalytic combustion technology is one of the most important and effective means for the purification and treatment of VOCs pollutants, and the development of low-cost, high-efficiency, stable and broad-spectrum catalysts is the key to the application of this technology. Molecular sieves such as ZSM-5, BETA or USY have large specific surface area, regular pore structure, and rich acidic sites, and are widely used in the fields of separation,...

AI Technical Summary

Problems solved by technology

In addition, molecular sieves such as ZSM-5 are often used as supports for supported catalysts, but the surface of these microporous molecular sieves is relatively smooth, which is not conducive to the highly dispersed loading of active components such as noble metals and limits their wide application. Therefore, improving their pore structure and surface properties, will also promote high dispersion of active components and improve their catalytic performance

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