Modified perovskite catalyst and its preparation method and application

Abstract

The invention relates to a modified perovskite catalyst, which includes a carrier, M elements, noble metal elements and non-metallic elements, and the material of the carrier is LaVO 3 , the M element includes at least one of Ce, Nb, and Zr, and the non-metallic element includes C and / or S, wherein, the M element is loaded on the carrier and / or enters the crystal structure of the carrier to replace part of the La element, and the noble metal element is loaded Part of the V element is replaced on the carrier and / or into the crystal structure of the carrier, and the non-metal element is loaded on the carrier and / or into the crystal structure of the carrier to replace part of the O element. The invention also relates to a preparation method and application of the modified perovskite catalyst. When the modified perovskite catalyst of the present invention is used as a catalyst for catalytic wet oxidation degradation of salty wastewater, it can effectively promote the decomposition of organic matter. At the same time, the surface of the modified perovskite catalyst is not easy to coke, and it can Loop application, long service life.

Description

technical field [0001] The invention relates to the technical field of catalytic wet oxidation, in particular to a modified perovskite catalyst and its preparation method and application. Background technique [0002] Catalytic wet oxidation technology (CWAO) is an effective technology developed in the 1980s to treat high-concentration, toxic, harmful, and biodegradable wastewater. The main principle of this technology is: under the action of a catalyst, at a lower temperature , pressure, oxygen or air atmosphere, efficiently oxidize organic molecules, ammonia nitrogen, sulfide, etc. in wastewater into CO 2 , SO 2 , NO 2 etc., to achieve the purpose of wastewater purification. [0003] The catalysts used in CWAO technology are divided into homogeneous catalysts and heterogeneous catalysts. Homogeneous catalysts are mostly soluble iron salts, copper salts, nickel salts, etc. Although these catalysts are cheap and efficient, they are difficult to separate later and easily ...

AI Technical Summary

Problems solved by technology

Homogeneous catalysts are mostly soluble iron salts, copper salts, nickel salts, etc. Although these catalysts are cheap and efficient, they are difficult to separate later and easily cause secondary pollution

Compared with homogeneous catalysts, heterogeneous catalysts have the advantages of simple separation and reusability, so they have become a current research hotspot. However, heterogeneous catalysts have problems such as low dispersion of active components, easy loss, and easy coking on the catalyst surface. still unresolved

[0004] In this regard, the patent CN102451713A introduced a catalyst prepared by impregnating Cu-Zn-Pt on activated carbon for the treatment of phenol-containing wastewater. However, this catalyst prepared by loading transition metals and noble metals on the carrier, During the use process, transition metals are often lost, which will not only reduce the performance of the catalyst, shorten the service life, but also cause secondary pollution.

[0005] Patent CN102101053A introduces a metal carbonyl supported on γ-Al 2 o 3 or TiO 2 The catalyst prepared above is used to treat high-concentration organic wastewater. However, this patent avoids the problem of coking and loss of the catalyst by reducing the loading of active components. If the content of organic matter in the wastewater is high, it will cause treatment The effect is not good, or it is necessary to extend the treatment time to achieve the treatment effect, which will not only reduce the amount of wastewater treatment, but also increase the operating cost

[0006] Patent CN1531997A introduces a method of solid-phase crystallization to prepare perovskite composite oxide-supported palladium catalyst. Although metal palladium can be uniformly dispersed on the surface of the catalyst, the precious metal particles are dispersed into the catalyst during the solid-phase crystallization process. The surface is easily affected by factors such as reduction temperature and gas atmosphere; in addition, the Co element in the catalyst is easily lost during use, which not only causes secondary pollution, but also affects the phase structure of the catalyst

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