A monolithic catalyst having perovskite oxide skeleton and preparation method thereof

Abstract

The invention discloses a monolithic catalyst having a perovskite oxide skeleton and a preparation method of the monolithic catalyst. According to the catalyst, honeycomb ceramic with honeycomb ductsis used as a carrier; a perovskite oxide nanoparticle coating is arranged on the surfaces of the honeycomb ducts, a perovskite oxide skeleton layer is directly arranged on the perovskite oxide nanoparticle coating, and perovskite oxide skeletons are provided with hollow holes which are communicated with one another. According to the invention, the perovskite oxide skeleton layer is directly arranged on the perovskite oxide nanoparticle coating; therefore, the perovskite oxide skeleton layer can be fixed in the honeycomb duct without using an adhesive; compared with a traditional powder type coating catalyst, the macroporous structure can greatly improve the mutual contact between the catalyst and gas-phase small molecules, increase catalytic reaction active sites and improve the diffusionefficiency of gas-phase reactants, thereby improving the catalytic efficiency of the catalyst.

Description

technical field [0001] The invention belongs to the field of environmental protection, in particular to a catalyst with a perovskite oxide framework and a manufacturing method thereof, in particular to a method for directly growing a three-dimensional ordered macroporous perovskite oxide framework onto the surface of a cordierite honeycomb ceramic . Background technique [0002] For nearly half a century, with the gradual increase in the degree of global industrial automation and technology, the problem of environmental pollution has become more and more serious. The first to bear the brunt is the problem of air pollution in cities. As the number of motor vehicles worldwide increases year by year, carbon monoxide (CO), hydrocarbons (CHx), nitrogen oxides (NOx) and other pollution emitted from internal combustion engines of motor vehicles Reactive gases are extremely harmful to human health, so governments and institutions around the world have successively formulated increa...

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Problems solved by technology

[0004] The invention patent of Chinese Patent Publication No. CN 104399480A discloses a method for preparing a monolithic three-dimensional ordered macroporous structure perovskite catalyst. The polystyrene colloidal crystal template is assembled by centrifugation, and then metal ions are mixed with nitric acid by impregnation. The salt precursor is filled into the template, and finally the template is removed by high-temperature calcination to obtain a three-dimensional ordered macroporous structure perovskite catalyst; the three-dimensional ordered macroporous catalyst obtained above is a monolithic macroporous aggregate, which cannot be applied onto the actual cordierite support;

[0006] The monolithic three-dimensional ordered macroporous catalyst prepared by the above method needs to be coated with a layer of γ-Al 2 o 3 coating, while γ-Al 2 o 3 It is easy to undergo phase change at high temperature, and it is easy to reduce the overall stability of the catalyst at high temperature, and γ-Al 2 o 3 The coating of the sol coating will also increase the cost of catalyst preparation; in addition, the cordierite will be acid-treated in this method, which will also have a certain impact on the structural stability of the cordierite substrate; therefore, there is a special need for a A method of directly growing a three-dimensional ordered macroporous perovskite oxide catalyst on a cordierite substrate without a binder to solve the above-mentioned existing problems

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