阅读说明：本技术 一种高性能汽车尾气净化催化剂及其制备方法 (High-performance automobile exhaust purification catalyst and preparation method thereof ) 是由 朱小勇 于 2019-01-17 设计创作，主要内容包括：本发明公开了一种高性能汽车尾气净化催化剂及其制备方法,上述制备方法包括如下步骤：S1、将铈锆复合氧化物放入储料桶内,然后将贵金属溶液以喷淋的方式加入,喷淋完成后继续搅拌10～60分钟；S2、将分散剂加至步骤S1中的储料桶内并搅拌,干燥,焙烧,得到催化剂粉末A；S3、将去离子水和步骤S2所得催化剂粉末A加入搅拌机内,搅拌均匀后,依次加入金属氧化物助剂、粘结剂、分散剂,搅拌,静置,搅拌,球磨,得到pH为10.5-14的碱性浆料；S4、将蜂窝陶瓷载体浸渍于步骤S3所得浆料中1～3分钟,去除多余浆料,风刀吹扫,干燥,焙烧,得到汽车尾气净化催化剂。本发明公开的该催化剂活性高、寿命长,对汽车尾气处理具有优异的效果,制备方法简单、成本低。(The invention discloses a high-performance automobile exhaust purification catalyst and a preparation method thereof, wherein the preparation method comprises the following steps: s1, putting the cerium-zirconium composite oxide into a storage barrel, adding the precious metal solution in a spraying manner, and continuing stirring for 10-60 minutes after spraying is finished; s2, adding a dispersing agent into the storage barrel in the step S1, stirring, drying and roasting to obtain catalyst powder A; s3, adding deionized water and the catalyst powder A obtained in the step S2 into a stirrer, stirring uniformly, sequentially adding a metal oxide auxiliary agent, a binder and a dispersing agent, stirring, standing, stirring and ball-milling to obtain alkaline slurry with the pH of 10.5-14; and S4, dipping the honeycomb ceramic carrier into the slurry obtained in the step S3 for 1-3 minutes, removing redundant slurry, blowing by using an air knife, drying, and roasting to obtain the automobile exhaust purification catalyst. The catalyst disclosed by the invention has the advantages of high activity, long service life, excellent effect on automobile exhaust treatment, simple preparation method and low cost.)

1. The high-performance automobile exhaust purification catalyst is characterized by comprising a wall-flow honeycomb ceramic carrier and a coating loaded on the wall-flow honeycomb ceramic carrier, wherein the loading amount of the coating is 150-200 g/L, and the coating loaded on the wall-flow honeycomb ceramic carrier comprises the following raw materials, by weight, 50-95 parts of a cerium-zirconium composite oxide, 0.5-10 parts of a metal oxide auxiliary agent, 0.05-5 parts of a precious metal solution, 0.5-5 parts of a binder and 0.5-10 parts of a dispersing agent.

2. The high-performance automobile exhaust gas purification catalyst according to claim 1, wherein the mesh number of the wall-flow honeycomb ceramic is 200-900 meshes.

3. The high-performance automobile exhaust gas purification catalyst according to claim 1, wherein the cerium oxide is 5 to 50% by mass of the cerium-zirconium composite oxide.

4. The high-performance automobile exhaust gas purifying catalyst according to claim 1, wherein the metal oxide auxiliary is one or more selected from barium oxide, antimony oxide, and bismuth oxide.

5. The high-performance automobile exhaust gas purifying catalyst according to claim 1, wherein the noble metal solution is one or more selected from the group consisting of platinum nitrate, palladium nitrate, ruthenium nitrate, and rhodium nitrate.

6. The high-performance automobile exhaust gas purifying catalyst according to claim 1, wherein the binder is one or more selected from polyacrylic acid, tartaric acid, and hydroxyethyl cellulose.

7. The high-performance automobile exhaust gas purifying catalyst according to claim 1, wherein the dispersant is one or more selected from the group consisting of ammonia water, ethanolaminum, barium hydroxide, and tetramethylammonium hydroxide.

8. The method for producing a high-performance automobile exhaust gas purifying catalyst according to any one of claims 1 to 7, comprising the steps of:

s1, putting the cerium-zirconium composite oxide into a storage barrel, adding the precious metal solution in a spraying mode, stirring while adding, wherein the solid content is 60-70%, and continuously stirring for 10-60 minutes after the precious metal solution is sprayed;

s2, slowly dropwise adding a dispersing agent into the storage barrel in the step S1, wherein the solid content is 50-60%, continuously stirring for 20-30 minutes after dropwise adding is completed, drying in an oven at 100-200 ℃ for 1-2 hours, and roasting at 500-600 ℃ for 0.5-3 hours to obtain catalyst powder A;

s3, sequentially adding deionized water and the catalyst powder A obtained in the step S2 into a stirrer, stirring for 10-15 minutes, sequentially adding a metal oxide auxiliary agent, a binder and a dispersing agent, continuously stirring for 15-30 minutes, stopping stirring, standing for 2-4 hours, stirring again, adding a pH regulator while stirring to adjust the pH to 10.5-14, and finally transferring to a ball milling tank for ball milling for 0.1-1 hour to obtain alkaline slurry;

and S4, dipping the wall-flow honeycomb ceramic carrier in the slurry obtained in the step S3 for 1-3 minutes, removing redundant slurry, blowing by using an air knife, drying at 100-150 ℃, and finally roasting at 500-550 ℃ for 1-2 hours to obtain the high-performance automobile exhaust purification catalyst with the active component layer carrying capacity of 150-200 g/L.

Technical Field

The invention relates to the technical field of automobile exhaust treatment, in particular to a high-performance automobile exhaust purification catalyst and a preparation method thereof.

Background

The soaring of national economy and the great improvement of the living standard of people are followed by the driving force of the rapid development of the automobile industry. The high-speed increase of the automobile holding capacity in the world brings about the continuous rising of the emission of the pollutants in the tail gas. Automobile exhaust contains hundreds of different substances, the main pollutants of which are carbon monoxide (CO), Hydrocarbons (HC) and nitrogen oxides (NOx).

The preparation methods of the coating in the existing catalyst for treating the automobile exhaust are mainly divided into two methods: 1. mixing palladium and rhodium to prepare slurry for coating; 2. and respectively preparing palladium and rhodium into slurry and then coating the slurry layer by layer. In the first preparation method, palladium and rhodium are easy to form alloy under high temperature condition, so that the catalytic activity is influenced, and the second preparation method has complex process and high manufacturing cost. Therefore, there is a need to find a new catalyst for treating automobile exhaust, which has a low cost and no influence on the performance of the catalyst.

Disclosure of Invention

The invention aims to overcome the defects and provides a high-performance automobile exhaust purification catalyst and a preparation method thereof, the catalyst has high activity and long service life, has excellent effects on treatment of CO, HC, NOx and PM, and is simple in preparation method and low in cost.

In order to achieve the above object, the present invention provides a technical solution,

the invention provides a high-performance automobile exhaust purification catalyst which comprises a wall-flow honeycomb ceramic carrier and a coating loaded on the wall-flow honeycomb ceramic carrier, wherein the loading amount of the coating is 150-200 g/L, and the coating loaded on the wall-flow honeycomb ceramic carrier comprises the following raw materials, by weight, 50-95 parts of a cerium-zirconium composite oxide, 0.5-10 parts of a metal oxide auxiliary agent, 0.05-5 parts of a precious metal solution, 0.5-5 parts of a binder and 0.5-10 parts of a dispersing agent.

Furthermore, the mesh number of the wall-flow honeycomb ceramic is 200-900 meshes.

Further, the cerium oxide in the cerium-zirconium composite oxide is 5-50% by mass.

Further, the metal oxide auxiliary agent is selected from one or more of barium oxide, antimony oxide and bismuth oxide.

Further, the noble metal solution is selected from one or more of platinum nitrate, palladium nitrate, ruthenium nitrate and rhodium nitrate.

Further, the binder is selected from one or more of polyacrylic acid, tartaric acid and hydroxyethyl cellulose.

Further, the dispersing agent is selected from one or more of ammonia water, ethanol ammonia, barium hydroxide and tetramethyl ammonium hydroxide.

The invention provides a preparation method of the high-performance automobile exhaust purification catalyst, which comprises the following steps:

s1, putting the cerium-zirconium composite oxide into a storage barrel, adding the precious metal solution in a spraying mode, stirring while adding, wherein the solid content is 60-70%, and continuously stirring for 10-60 minutes after the precious metal solution is sprayed;

s2, slowly dropwise adding a dispersing agent into the storage barrel in the step S1, wherein the solid content is 50-60%, continuously stirring for 20-30 minutes after dropwise adding is completed, drying in an oven at 100-200 ℃ for 1-2 hours, and roasting at 500-600 ℃ for 0.5-3 hours to obtain catalyst powder A;

s3, sequentially adding deionized water and the catalyst powder A obtained in the step S2 into a stirrer, stirring for 10-15 minutes, sequentially adding a metal oxide auxiliary agent, a binder and a dispersing agent, continuously stirring for 15-30 minutes, stopping stirring, standing for 2-4 hours, stirring again, adding a pH regulator while stirring to adjust the pH to 10.5-14, and finally transferring to a ball milling tank for ball milling for 0.1-1 hour to obtain alkaline slurry;

and S4, dipping the wall-flow honeycomb ceramic carrier in the slurry obtained in the step S3 for 1-3 minutes, removing redundant slurry, blowing by using an air knife, drying at 100-150 ℃, and finally roasting at 500-550 ℃ for 1-2 hours to obtain the high-performance automobile exhaust purification catalyst with the active component layer carrying capacity of 150-200 g/L.

Compared with the prior art, the invention has the beneficial effects that: the invention overcomes the problems of poor aging performance, complex production process and high preparation cost of the existing automobile exhaust purification catalyst; the high-performance automobile exhaust purification catalyst provided by the invention has the advantages of high activity, long service life, excellent effect on treatment of CO, HC, NOx and PM, simple preparation method and low cost.

Drawings

FIG. 1 is a graph showing the variation of the performance test of a high-performance catalyst for purifying automobile exhaust gas according to the present invention.

Detailed Description

In order to make the technical means, the characteristics, the purposes and the functions of the invention easy to understand, the invention is further described with reference to the specific drawings.