A catalyst for treating exhaust emissions from methanol fuel engines and its preparation method and application

Abstract

The present invention provides a catalyst for treating exhaust gas of methanol fuel automobiles, the catalyst comprising a first active component containing precious metals coated on a carrier, and a second active component containing one or more zirconium oxide materials of manganese, titanium and copper; the first active component is coated on the first layer of the carrier, and the second active component is coated on the upper layer of the first active component; or the first active component is coated on the rear area of ​​the first layer of the carrier, and the second active component is coated on the front area of ​​the first layer of the carrier; the front area of ​​the first layer is the exhaust gas inlet end part, and the rear area of ​​the first layer is the exhaust gas outlet end part. The amount of formic acid generated by the catalyst at low temperature is significantly lower than that of the reference catalyst, the catalyst increases the low-temperature activity of formic acid, and the generation of cyanide is not detected, thereby avoiding the problem of formic acid reacting with ammonia to generate cyanide.

Description

Technical Field

[0001] The invention belongs to the field of tail gas treatment of methanol fuel engine vehicles, and in particular relates to a catalyst for treating tail gas discharged from methanol fuel engine vehicles. Background Art

[0002] With the increasing number of cars, automobile exhaust emissions have brought serious impacts on the environment and human health. Formaldehyde and formic acid are the main harmful substances in the exhaust of methanol-fueled cars, which have potential harm to air quality and human health. Therefore, it is of great significance to develop efficient catalysts for exhaust treatment of methanol-fueled cars, especially catalysts for reducing formaldehyde and formic acid emissions during cold start.

[0003] At present, the catalysts used to convert formaldehyde and formic acid in the exhaust gas of methanol-fueled vehicles mainly use traditional catalysts containing precious metals. Precious metals such as platinum, palladium and rhodium have high catalytic activity and stability and can effectively degrade formaldehyde and formic acid. These precious metals are usually coated on carriers such as honeycomb ceramics to form catalysts.

[0004] However, there are the following problems in the prior art: first, the cost of precious metal catalysts is relatively high. Secondly, the catalytic activity of precious metal catalysts for formaldehyde and formic acid in the exhaust gas of methanol fueled vehicles is limited to a certain extent, especially during cold start, when the exhaust gas and post-processing temperature of the vehicle are relatively low, the activity of the catalyst for formic acid will be reduced or even completely ineffective. Finally, when the methanol fueled engine is started, the fuel remaining in the engine gap is oxidized to produce a large amount of formaldehyde and formic acid. For a methanol fueled engine using a urea aqueous solution and an ammonia-containing antifreeze post-processing system, the discharged formic acid contacts and reacts with the residual ammonia in the post-processing (mainly a mixer and a selective catalytic reduction catalyst, etc.) to generate cyanide, which causes potential harm to the environment and human health. In summary, the prior art has the problems of low catalytic activity and high cost in the development of methanol fueled vehicle exhaust catalysts, and the problem of formic acid reacting with ammonia to generate cyanide in the post-processing of methanol lean-burn engines. Therefore, it is necessary to develop a new catalyst that can solve the above problems while reducing the emission of formaldehyde and formic acid. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a catalyst for treating exhaust gas from methanol-fueled vehicles. Different catalysts are coated in sections, and a first active component and a second active component are used in combination. The coating amount of the active component containing precious metals is reduced without reducing the methanol conversion performance of the catalyst, and the reduced activity of the catalyst to formic acid and formaldehyde is overcome, and the problem that the discharged formic acid contacts and reacts with residual ammonia to generate cyanide is overcome.

[0006] The present invention provides a catalyst for treating exhaust gas from methanol fueled automobiles, the catalyst comprising a first active component containing precious metals coated on a carrier, and a second active component containing one or more zirconium oxide materials of manganese, titanium and copper; the first active component is coated on the first layer of the carrier, and the second active component is coated on the upper layer of the first active component; or the first active component is coated on the rear area of ​​the first layer of the carrier, and the second active component is coated on the front area of ​​the first layer of the carrier; the front area of ​​the first layer is the exhaust gas inlet end part, and the rear area of ​​the first layer is the exhaust gas outlet end part.

[0007] As some embodiments of the present invention, the carrier is selected from honeycomb ceramics and metal carriers.

[0008] As certain embodiments of the present invention, the noble metal of the first active component containing the noble metal is one or more metal oxides containing Pt, Rh, and Pd.

[0009] As certain embodiments of the present invention, the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper is a high-porosity porous material.

[0010] As some embodiments of the present invention, the total amount of precious metal in the first active component containing precious metal is 5 to 150 gpcf. As some embodiments of the present invention, the total amount of precious metal in the first active component containing precious metal is 30 to 90 gpcf.

[0011] 100, 105, 110, 115, 120, 130, 135, 140, 145, 150, 155, 160 gpcf.

[0012] As certain embodiments of the present invention, the coating amount of the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper is 1-40% of the coating amount of the first active component containing the precious metal.

[0013] The coating amount of the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40% of the coating amount of the first active component containing the precious metal.

[0014] As certain embodiments of the present invention, the ratios of manganese, titanium and copper in the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper are: manganese / zirconium (wt%): 0-40%; titanium / zirconium (wt%): 0-40%; copper / zirconium (wt%): 0-10%.

[0015] The manganese ratio is selected from manganese / zirconium (wt%): 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40%.

[0016] The titanium ratio is selected from titanium / zirconium (wt%): 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40%.

[0017] The copper ratio is selected from copper / zirconium (wt%): 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20%.

[0018] As certain embodiments of the present invention, the first active component is coated by top-loading coating or bottom-pushing slurry coating.

[0019] Top-loading coating refers to a coating method in which the coating slurry is sucked into the carrier from above the carrier.

[0020] Push-down slurry coating refers to a coating method in which the coated slurry is squeezed into the carrier from below the carrier.

[0021] As certain embodiments of the present invention, the second active component is applied by a sol-gel method or a dipping method.

[0022] As certain embodiments of the present invention, the second active component is prepared by a sol-gel coating method by mixing one or more easily hydrolyzable precursor salts containing manganese, titanium, and copper with a zirconium-containing material and dissolving them in deionized water, adding 0.5 to 5 times the mass of the precursor salt of citric acid, and then adding 2% to 30% of the mass of citric acid of polyethylene glycol, and drying after hydrolysis and condensation to form a sol, and finally forming an active component after heat treatment at a high temperature of 400 to 700°C.

[0023] The amount of citric acid added in the sol-gel coating method is selected from 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, and 5 times the mass of the precursor salt.

[0024] The amount of polyethylene glycol added in the sol-gel coating method is selected from 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30% of the mass of citric acid.

[0025] The temperature of the high temperature heat treatment in the sol-gel coating method is selected from 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700°C.

[0026] As certain embodiments of the present invention, the second active component is prepared by an impregnation method, which is to immerse one or more precursor salt media containing manganese, titanium, and copper in a zirconium-containing material, allowing the medium to penetrate into the surface of the material and form a coating, and then calcining at a high temperature of 400 to 700°C to form the active component.

[0027] The high temperature calcination temperature in the preparation by impregnation method is selected from 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700°C.

[0028] As certain embodiments of the present invention, the second active component prepared by the sol-gel method or the impregnation method is mixed with deionized water to form a slurry with a solid content of 10-60% w / w, which is then stirred and ground to obtain the desired second active component slurry.

[0029] The solid content of the slurry is selected from 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60% w / w.

[0030] As certain embodiments of the present invention, the length of the first layer rear region of the carrier is greater than or equal to 1 / 2 of the length of the carrier; the first layer front region of the carrier is less than or equal to the front half of 1 / 2 of the length of the carrier.

[0031] The present invention provides a method for preparing the catalyst, which comprises the following steps: coating a first active component on the first layer of the carrier, and coating a second active component on the first layer coated with the first active component as the second layer; or coating the first active component in the rear area of ​​the first layer of the carrier, and coating the second active component in the front area of ​​the first layer of the carrier; the front area of ​​the first layer of the carrier is the exhaust gas inlet end part, and the rear area of ​​the first layer of the carrier is the exhaust gas outlet end part; wherein the first active component is a first active component containing a precious metal, wherein the precious metal is one or more metal oxides containing Pt, Rh, and Pd, and the second active component is a zirconium oxide material containing one or more types of manganese, titanium or copper.

[0032] As some embodiments of the present invention, the carrier is selected from honeycomb ceramics and metal carriers.

[0033] As some embodiments of the present invention, the total amount of precious metal in the first active component containing precious metal is 5 to 150 gpcf. As some embodiments of the present invention, the total amount of precious metal in the first active component containing precious metal is 30 to 90 gpcf.

[0034] As certain embodiments of the present invention, the coating amount of the second active component of the zirconium oxide material containing one or more of manganese, titanium and / or copper is 1-40% of the coating amount of the first active component containing the precious metal.

[0035] As certain embodiments of the present invention, the ratios of manganese, titanium and copper in the second active component of the zirconium oxide material containing one or more of manganese, titanium and / or copper are: manganese / zirconium (wt%): 0-40%; titanium / zirconium (wt%): 0-40%; copper / zirconium (wt%): 0-10%.

[0036] As certain embodiments of the present invention, in step (1), the first active component is coated by top-loading coating or bottom-pushing slurry coating; in step (2), the second active component is coated by sol-gel method or dipping method.

[0037] As certain embodiments of the present invention, the second active component in step (2) is prepared by a sol-gel coating method, which is to mix one or more easily hydrolyzable precursor salts containing manganese, titanium, and copper with a zirconium-containing material and dissolve them in deionized water, add 0.5 to 5 times the mass of the precursor salt of citric acid, and then add 2% to 30% of the mass of citric acid of polyethylene glycol, and then dry it after hydrolysis and condensation to form a sol, and finally heat treat it at a high temperature of 400 to 700°C to form an active component.

[0038] As certain embodiments of the present invention, the second active component is prepared by an impregnation method, which is to immerse one or more precursor salt media containing manganese, titanium, and copper in a zirconium-containing material, then allow the medium to penetrate into the surface of the material and form a coating, and then calcine at a high temperature of 400 to 700°C to form an active component.

[0039] As certain embodiments of the present invention, the second active component prepared by the sol-gel method or the impregnation method is mixed with deionized water to form a slurry with a solid content of 10-60%, which is then stirred evenly and ground to obtain the desired second active component slurry.

[0040] As certain embodiments of the present invention, the length of the rear region of the first layer of the carrier is greater than or equal to 1 / 2 of the length of the carrier; the length of the front region of the first layer of the carrier is less than or equal to 1 / 2 of the length of the carrier.

[0041] The invention also provides use of the catalyst in catalytic treatment of methanol fuel automobile tail gas.

[0042] As described above, the catalyst for treating exhaust gas emitted by a methanol fuel engine vehicle of the present invention and its preparation method and application have the following beneficial effects:

[0043] 1. Coating the first active component containing precious metals on the first layer or the rear area of ​​the first layer of honeycomb ceramics. This technical means can meet the degradation efficiency of methanol, formaldehyde and formic acid in the middle and high temperature range of exhaust temperature, thereby meeting the catalyst activity requirements.

[0044] 2. Coat one or more zirconium oxide materials containing manganese, titanium or copper on the second layer of honeycomb ceramics or the front area of ​​the first layer as the second active component. This technical means can reduce the demand for precious metals and reduce the cost of the catalyst. The second active component can form a layer of high-porosity components on the surface of the first active component or the carrier, adsorbing formaldehyde and formic acid at low temperatures and releasing formaldehyde and formic acid at high temperatures. This will improve the degradation efficiency of the catalyst for formaldehyde and formic acid.

[0045] The structure of the catalyst can also prevent formic acid generated by cold start of a methanol lean-burn engine from contacting with residual ammonia in post-treatment (mainly mixer and selective catalytic reduction catalyst, etc.) and reacting to form cyanide. That is, the presence of the second active component can adsorb formaldehyde and formic acid at low temperatures and release formaldehyde and formic acid at high temperatures. Avoiding contact between formic acid and ammonia at low temperatures prevents the generation of cyanide, thereby effectively reducing potential harm to the environment and human health.

[0046] 3. The second active component and the first active component of the catalyst of the present invention have a synergistic effect, which increases the conversion efficiency of methanol, formaldehyde and formic acid at medium and high temperatures.

[0047] In summary, the technical solution of the present application improves the catalytic activity of the catalyst, reduces costs, and avoids the reaction of formic acid and ammonia to generate cyanide by coating the first layer or the rear area of ​​the first layer of the honeycomb ceramic with the first active component, and coating the second layer or the front area of ​​the first layer with the second catalytic test. This can effectively achieve cost reduction, significantly reduce formaldehyde and formic acid emissions when the emission temperature is lower than 300°C, and prevent the emission of methanol lean-burn engines from generating cyanide through the combined action of the first active component and the second active component. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 Shown is a curve chart showing changes in methanol conversion rate, formic acid and cyanide production in a methanol lean-burn engine bench with catalysts in the embodiments of the present invention and the reference examples as a function of temperature. DETAILED DESCRIPTION

[0049] The present invention is further described below in conjunction with specific examples, and it should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0050] It should be understood that the terms used in the examples of the present invention are intended to describe specific embodiments rather than to limit the scope of protection of the present invention; in the present specification and claims, unless otherwise expressly stated, the singular forms "a", "an" and "the" include plural forms. When the examples give numerical ranges, it should be understood that unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected.

[0051] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, any methods, equipment, and materials of the prior art that are similar or equivalent to the methods, equipment, and materials in the embodiments of the present invention may be used to implement the present invention, based on the prior art mastery of those skilled in the art and the description of the present invention.

[0052] Unless otherwise stated, the experimental methods, detection methods, and preparation methods disclosed in the present invention all adopt conventional techniques in the technical field and related fields.

[0053] Preparation Example 1 Preparation method of methanol fuel automobile exhaust catalyst of the present invention

[0054] The structure of the catalyst of the present application includes a first layer and / or a second layer coated on a honeycomb ceramic, the first layer is coated with a traditional catalyst containing precious metals, the second layer is coated with a zirconium oxide material containing one or more of manganese, titanium and copper, or the rear area of ​​the first layer is coated with a traditional catalyst containing precious metals, and the front area of ​​the first layer is coated with a zirconium oxide material containing one or more of manganese, titanium and copper. The front area of ​​the first layer is the exhaust gas inlet end part, and the rear area of ​​the first layer is the exhaust gas outlet end part. The specific preparation method is as follows:

[0055] Step 1: Prepare a coating containing a conventional catalyst containing precious metals. A metal solution with a total amount of 50 gpcf (grams per cubic foot) and a precious metal ratio of Pt / Rh / Pd = 5:2:1 is stirred and mixed with a metal oxide material containing cerium and aluminum, and then ground to form a slurry.

[0056] Step 2: Coating the first layer or the rear area of ​​the first layer. The slurry obtained in step 1 is uniformly coated on the rear area of ​​the first layer of the honeycomb ceramic by a push-down slurry method. The coating length is 1 / 2 of the carrier length.

[0057] Step 3: Fix the coating: The coating is fixed on the first layer rear area of ​​the honeycomb ceramic by a sintering process at 500°C / 2h in air atmosphere.

[0058] Step 4: Prepare a slurry of zirconium oxide material containing manganese and titanium. 4 H 6 MnO 4 ·4H2 O:1Ti(NO 3 ) 2 :7Zr(NO 3 ) 4 (C 4 H 6 MnO 4 ·4H 2 O and Ti (NO 3 ) 2 and Zr(NO 3 ) 4 The molar ratio is 2:1:7) as the precursor, and the solution-sol method is used. First, the above precursor is dissolved in deionized water, and citric acid with a mass of 2 times the mass of manganese and titanium ions is added (the mass of citric acid is 2 times the mass of manganese and titanium elements), and then polyethylene glycol with a mass of 10% citric acid is added, and stirred at 80°C until the solution is precipitated and transparent. Finally, it is dried at 110°C for 2h and transferred to a 500°C muffle furnace and calcined in air atmosphere for 5h. The manganese and titanium-containing zirconium oxide material prepared by the solution-sol method is configured with deionized water to form a water-based coating with a solid content of 35%.

[0059] Step 5: Coating the front area of ​​the first layer. The slurry obtained in step 4 is uniformly coated on the front area of ​​the first layer of the honeycomb ceramic by a push-down slurry method. The coating length is 1 / 2 of the carrier length, and the coating amount is 20% of the coating amount of the first active component.

[0060] Step 6: Fix the coating: The coating is fixed on the first front layer of the honeycomb ceramic by a sintering process at 500°C / 2h in air atmosphere.

[0061] Preparation Example 2

[0062] Steps 1, 2 and 3 of Example 1 were repeated to obtain a honeycomb ceramic carrier catalyst containing a first layer rear zone and having the same precious metal concentration ratio.

[0063] Step 4: Prepare a slurry of zirconium oxide material containing manganese and titanium in the same proportion as in Example 1. Dissolve manganese nitrate and titanium nitrate in deionized water and impregnate them on zirconium oxide powder by impregnation. Then dry at 110°C for 2 hours and transfer to a muffle furnace at 650°C and calcine in air atmosphere for 2 hours. The zirconium oxide material containing manganese and titanium prepared by the impregnation method is configured into a water-based coating with a solid content of 35%.

[0064] Steps 5 and 6 of Example 1 were repeated to finally obtain a catalyst.

[0065] Reference ratio:

[0066] Repeat the above steps 1, 2 and 3 to obtain the same precious metal concentration ratio, and the coating amount is the same as the total amount of the first active component and the second active component of the finished catalyst product prepared by the embodiment of the present application.

[0067] Catalyst performance evaluation: The catalyst prepared above was packaged and tested on a methanol lean-burn engine bench for the catalyst steady-state methanol conversion efficiency and formic acid and cyanide emissions according to GB17691-2018 regulations. The results are shown in the attached Figure 1 shown.

[0068] Example 3 Catalytic Effects of Catalysts Prepared in Examples 1, 2 and Reference Examples

[0069] Engine bench test results Figure 1 It can be seen that:

[0070] 1. The conversion performance of the pollutants of the catalysts obtained after coating the second active component prepared by two different methods in Preparation Examples 1 and 2 is basically the same.

[0071] 2. The conversion performance of the three catalyst samples on methanol is basically the same, and the performance of the catalyst of the present invention on methanol conversion is slightly better in the low temperature range, indicating that the catalysts of Preparation Examples 1 and 2 can achieve the same catalytic performance requirements at a lower cost.

[0072] 3. The amount of formic acid generated by the catalyst of the present invention at low temperatures is significantly lower than that of the reference catalyst, indicating that the coated first layer of front zone components increases the low-temperature activity of the catalyst for formic acid.

[0073] 4. The catalyst of the present invention has not been detected to generate cyanide, indicating that the coated first layer of the front zone component avoids the problem of formic acid reacting with ammonia to generate cyanide.

[0074] 5. The precious metal ratio and coating amount of the first active component prepared by two different methods in Preparation Examples 1 and 2 are lower than those of the catalyst of the reference sample, but the methanol conversion efficiency of the catalysts of the two examples is basically the same as that of the reference sample. This shows that the second active component of the present invention and the first active component have a synergistic effect, which ensures the methanol conversion efficiency.

[0075] In summary, the preparation method of the catalyst is simple and low in cost. It is suitable for the catalytic degradation of formaldehyde and formic acid emitted during cold start of a methanol lean-burn engine, avoiding the reaction of formic acid and ammonia to form cyanide, and can be produced and applied on a large scale.

[0076] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the method of the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and evolutions of the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. Use of a catalyst for treating exhaust gas from a methanol fuel vehicle in catalytically treating exhaust gas from a methanol fuel vehicle, It is characterized in that The catalyst comprises a first active component containing a noble metal and a second active component of a zirconium oxide material containing one or more of manganese, titanium and copper coated on a carrier; The first active component is coated on the first layer of the carrier, and the second active component is coated on the upper layer of the first active component; Or the first active component is coated on the rear region of the first layer of the carrier, and the second active component is coated on the front region of the first layer of the carrier; The front area of ​​the first layer is the exhaust gas inlet end portion, and the rear area of ​​the first layer is the exhaust gas outlet end portion.

2. The use according to claim 1, It is characterized in that The carrier is selected from honeycomb ceramics and metal carriers; or the noble metal of the first active component containing the noble metal is one or more metal oxides containing Pt, Rh and Pd; Or the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper is a high-porosity porous material; or the total amount of precious metal in the first active component containing precious metal is 5 to 150 gpcf; Or the coating amount of the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper is 1-40% of the coating amount of the first active component containing the precious metal; Or the mass ratios of manganese, titanium and copper in the second active component of the zirconium oxide material containing one or more of manganese, titanium and copper are: manganese / zirconium 0-40%; titanium / zirconium 0-40%; copper / zirconium 0-10%, and the masses of manganese, titanium and copper are not zero at the same time.

3. The use according to claim 2, It is characterized in that The total amount of precious metal in the first active component containing precious metal is 30 to 90 gpcf.

4. The use according to any one of claims 1 to 3, It is characterized in that The first active component is coated by top-loading coating or bottom-pushing slurry coating; The second active component is prepared by a sol-gel method, which is to mix one or more easily hydrolyzable precursor salts containing manganese, titanium, and copper with a zirconium-containing material and dissolve them in deionized water, add citric acid in an amount of 0.5 to 5 times the mass of the precursor salt, and then add polyethylene glycol in an amount of 2% to 30% of the mass of the citric acid, and then dry the sol after hydrolysis and polycondensation, and finally form an active component after heat treatment at a high temperature of 400 to 700°C; or, the second active component is prepared by an impregnation method, which is to immerse a medium containing one or more precursor salts containing manganese, titanium, and copper in a zirconium-containing material, and then allow the medium to penetrate into the surface of the material and form a coating, and then calcine at a high temperature of 400 to 700°C to form an active component.

5. The use according to claim 4, It is characterized in that The second active component prepared by the sol-gel method or the impregnation method is mixed with deionized water to form a slurry with a solid content of 10-60%, and then ground after being stirred evenly to obtain the desired second active component slurry.

6. The use according to any one of claims 1 to 3, It is characterized in that The length of the rear region of the first layer of the carrier is greater than or equal to 1 / 2 of the length of the carrier; The length of the first layer front region of the carrier is less than or equal to 1 / 2 of the length of the carrier.

7. The use according to any one of claims 1 to 3, It is characterized in that The preparation method of the catalyst comprises the following steps: Coating a first active component on the first layer of the carrier, and coating a second active component on the first layer coated with the first active component as a second layer; or coating the first active component on the rear region of the first layer of the carrier, and coating the second active component on the front region of the first layer of the carrier; The front area of ​​the first layer of the carrier is the exhaust gas inlet end part, and the rear area of ​​the first layer of the carrier is the exhaust gas outlet end part; wherein the first active component is a first active component containing a precious metal, wherein the precious metal is one or more metal oxides containing Pt, Rh and Pd; The second active component is a zirconium oxide material containing one or more of manganese, titanium or copper.

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