A catalyst, its preparation and use

Abstract

The application provides a catalyst, a preparation method and use thereof, and the catalyst comprises a carrier, a first support and a second support; the first support comprises a first oxygen storage material, a titanium-aluminum composite oxide and a first active alumina, and a first active component is loaded on the first support; the second support comprises a second oxygen storage material and a second active alumina, and a second active component is loaded on the second support; the first active component is platinum and / or palladium; and the second active component comprises rhodium. The catalyst of the application has high conversion rate, can effectively purify harmful substances such as low-carbon alcohols, low-carbon aldehydes and low-carbon acids in automobile exhaust, and thus realizes low-pollutant emission and clean combustion.

Description

Technical Field

[0001] This invention relates to the field of exhaust gas purification technology, and in particular to a catalyst, its preparation method, and its uses. Background Technology

[0002] In the automotive industry, with increasing concern about environmental pollution, purifying vehicle exhaust emissions has become a crucial task. Given the growing environmental awareness, finding a fuel that can replace fossil fuels while also producing lower emissions has become an urgent need. Net-zero carbon fuels, specifically low-carbon alcohols, offer advantages such as high octane ratings, high latent heat of vaporization, and sustainability, making them the best alternative to fossil fuels. As a new generation of alternative fuels, net-zero carbon fuels, particularly low-carbon alcohols, can significantly reduce emissions of hydrocarbons (HC), CO, NOx, and particulate matter, and are widely used in the automotive sector as a more environmentally friendly fuel. However, during engine cold starts or idling, incomplete combustion of low-carbon alcohols can produce oxygen-containing intermediates such as aldehydes and acids, leading to exhaust pollution.

[0003] Patent CN102008958 A discloses a three-way catalyst for purifying gasoline vehicle exhaust and its preparation method. The catalyst has a double-layered catalytic active layer. The inner catalytic active layer is composed of activated alumina supported on one or more oxides of rare earth metals, alkaline earth metals, transition metals, and noble metals; the outer catalytic active layer is also composed of activated alumina supported on one or more oxides of rare earth metals, alkaline earth metals, and noble metals. The catalyst provided by this invention has a low ignition temperature and high catalytic conversion efficiency, effectively controlling the emission of conventional pollutants (CO, HC, NOx) during engine cold starts. However, its treatment effect on oxygen-containing intermediate products such as aldehydes and acids produced by the incomplete combustion of low-carbon alcohols is insufficient.

[0004] Therefore, it is of great significance to develop a catalyst that can efficiently treat oxygen-containing intermediates such as aldehydes and acids produced by the incomplete combustion of low-carbon alcohols. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a catalyst, its preparation method and uses, to solve the problems in the prior art.

[0006] To achieve the above and other related objectives, the present invention is obtained through the following technical solution.

[0007] The present invention provides a catalyst comprising a support on which a first support and a second support are loaded; the first support comprises a first oxygen storage material, a titanium-aluminum composite oxide, and a first activated alumina, and a first active component is loaded on the first support; the second support comprises a second oxygen storage material and a second activated alumina, and a second active component is loaded on the second support; the first active component is platinum and / or palladium; the second active component comprises rhodium.

[0008] Preferably, the carrier is selected from one or both of cordierite ceramic honeycomb carrier and metal honeycomb carrier.

[0009] Preferably, one or more of the first oxygen storage material, the titanium-aluminum composite oxide, and the first activated alumina are loaded with a first active ingredient.

[0010] Preferably, one or both of the second oxygen storage material and the second activated alumina are loaded with a second active ingredient.

[0011] Preferably, in the catalyst, the total mass ratio of palladium to rhodium is (1-20):2.

[0012] Preferably, in the catalyst, the total mass ratio of platinum to rhodium is (1-10):2.

[0013] Preferably, the second active ingredient further includes platinum and / or palladium.

[0014] Preferably, in the catalyst, the total loading of the first active component and the second active component is (0.01~50) g / ft. 3 .

[0015] Preferably, the content of the first support in the catalyst is 6-9 wt%.

[0016] Preferably, the content of the second support in the catalyst is 4-7 wt%.

[0017] Preferably, in the first support, the mass ratio of the first oxygen storage material, the first activated alumina, and the titanium-aluminum composite oxide is (20-30):(40-60):(5-10).

[0018] Preferably, in the second support, the mass ratio of the second oxygen storage material to the second activated alumina is (10-20):(50-70).

[0019] Preferably, the first oxygen storage material comprises a first transition metal oxide, which comprises one or more oxides of cerium, zirconium, lanthanum, scandium, and yttrium.

[0020] More preferably, based on the mass of the first oxygen storage material, the content of cerium oxide is 10-70 wt%, the content of zirconium oxide is 10-70 wt%, the content of lanthanum oxide is 20-70 wt%, the content of yttrium oxide is 1-10 wt%, and the content of scandium oxide oxide is 1-15 wt%.

[0021] More preferably, the first transition metal oxide further includes one or more oxides of praseodymium, neodymium, and samarium.

[0022] More preferably, the first oxygen storage material further includes a first alkaline earth metal oxide.

[0023] More preferably, the content of the first alkaline earth metal oxide in the first oxygen storage material is 0.01–5 wt%.

[0024] Preferably, the second oxygen storage material comprises a second transition metal oxide, which comprises one or both of oxides of cerium and zirconium.

[0025] More preferably, the second transition metal oxide is selected from one or more oxides of lanthanum, scandium, yttrium, praseodymium, neodymium, and samarium.

[0026] More preferably, based on the mass of the second oxygen storage material, the content of cerium oxide is 10-30 wt%, and the content of zirconium oxide is 50-80 wt%.

[0027] More preferably, the second oxygen storage material further includes a second alkaline earth metal oxide.

[0028] More preferably, the content of the second alkaline earth metal oxide in the second oxygen storage material is 0.01 to 3 wt%.

[0029] Preferably, the first oxygen storage material is prepared by the following method: mixing a soluble salt solution of each component in the first oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining.

[0030] Preferably, the second oxygen storage material is prepared by the following method: mixing a soluble salt solution of each component in the second oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining.

[0031] Preferably, the first active alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina, and samarium-modified alumina.

[0032] Preferably, the second active alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina, and samarium-modified alumina.

[0033] Preferably, the titanium dioxide content is 0.01 to 1.0 wt%, based on the mass of the catalyst.

[0034] Preferably, the oxygen storage material is prepared by the following method: mixing the soluble salt solutions of each component in the oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining.

[0035] Preferably, the salt solution of the first active ingredient is loaded onto one or more selected from the first oxygen storage material, titanium-aluminum composite oxide, and first activated alumina using an equal-volume impregnation method.

[0036] Preferably, the salt solution of the second active ingredient is loaded onto one or both of the second oxygen storage material and the second activated alumina using an equal-volume impregnation method.

[0037] The present invention also discloses a method for preparing the catalyst, the method being as follows:

[0038] A first slurry is provided, the first slurry is coated onto the carrier, and then calcined;

[0039] A second slurry is provided, which is then further coated onto the carrier, followed by further calcination.

[0040] The first slurry is formed by mixing powder formed from a first load body, a first binder, and water;

[0041] The second slurry is formed by mixing the powder formed from the second load body, the second binder, and water.

[0042] Preferably, the solid content of the first slurry is 32-38 wt%.

[0043] Preferably, the particle size of the powder formed by the first support is 3-12 μm.

[0044] Preferably, the solid content of the second slurry is 30-35 wt%.

[0045] Preferably, the particle size of the powder formed by the second support is 3-11 μm.

[0046] Preferably, the first binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose, and polyvinyl alcohol.

[0047] Preferably, the mass of the first binder accounts for 3 to 10 wt% of the mass of the powder formed by the first load body.

[0048] Preferably, the second binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose, and polyvinyl alcohol.

[0049] Preferably, the mass of the second binder accounts for 3 to 10 wt% of the mass of the powder formed by the second load body.

[0050] The present invention also discloses the use of the catalyst as a catalyst for purifying automobile exhaust.

[0051] Preferably, the catalyst is used for the catalytic oxidation of low-carbon alcohols, low-carbon aldehydes, and low-carbon carbonates in automobile exhaust.

[0052] Preferably, the low-carbon alcohols, low-carbon aldehydes, and low-carbon acids refer to C1-C4 alcohols, aldehydes, or acids.

[0053] This invention provides a catalyst, its preparation method, and its uses. The catalyst has the following beneficial effects:

[0054] 1. A certain proportion of Ti 4+ It readily reacts with adsorbed CO, thus increasing the CO conversion rate.

[0055] Moreover, TiO2 accelerates the transfer of adsorbed oxygen, further promoting the oxidation reaction of lower alcohols and the like.

[0056] 2. The introduction of scandium ions into the novel oxygen storage material can prevent the decline in oxygen storage performance caused by the growth of cerium oxide grains during calcination, and can also improve the activity and stability of the catalyst. Moreover, the scandium ions in the oxygen storage material synergistically enhance the activity and stability of the catalyst by working with transition metal oxides (such as oxides of cerium, zirconium, lanthanum, and yttrium).

[0057] 3. The new oxygen storage material has high oxygen storage capacity and stability, can effectively store oxygen, and release oxygen during cold start or idling, promote the complete combustion of low-carbon alcohols, low-carbon aldehydes and low-carbon carbonic acid, and reduce the probability of generating harmful substances.

[0058] 4. By adopting an active ingredient loading process, active ingredients Pt, Pd, and Rh are introduced into the catalyst coating in the form of powder loaded onto the coating material. This improves the dispersion, avoids the formation of precious metal alloys, reduces the amount of precious metals used, and improves the activity and stability of the catalyst. This significantly reduces the amount of precious metals used, thereby reducing the cost of the catalyst.

[0059] 5. By adopting a layered coating method, the active ingredients are evenly distributed, which improves the catalytic efficiency and stability of the catalyst, enhances the catalyst's ability to degrade harmful substances such as low-carbon alcohols, low-carbon aldehydes and low-carbon carbonates, and improves the catalyst's conversion rate and purification effect.

[0060] 6. The catalyst of this invention has a low ignition temperature and can start the reaction at a lower temperature, thereby reducing energy consumption and pollution emissions.

[0061] 7. The catalyst of this invention has a high conversion rate and can effectively purify harmful substances such as low-carbon alcohols, low-carbon aldehydes and low-carbon carbon dioxide in the exhaust gas of low-carbon alcohol vehicles, thereby achieving low pollutant emissions and clean combustion. Detailed Implementation

[0062] The following specific examples illustrate the implementation 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 various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0063] It should be noted that the process equipment or apparatus not specifically mentioned in the following embodiments are all conventional equipment or apparatus in the art.

[0064] Furthermore, it should be understood that the one or more method steps mentioned in this invention do not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, unless otherwise stated; moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or limiting the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered as within the scope of the invention.

[0065] This invention discloses a catalyst comprising a support on which a first support and a second support are loaded. The first support comprises a first oxygen storage material, a titanium-aluminum composite oxide, and a first activated alumina, and a first active component is loaded on the first support. The second support comprises a second oxygen storage material and a second activated alumina, and a second active component is loaded on the second support. The first active component is platinum and / or palladium, and the second active component includes rhodium.

[0066] In one specific embodiment, the carrier is selected from one or both of cordierite ceramic honeycomb carriers and metal honeycomb carriers.

[0067] In one specific embodiment, one or more of the first oxygen storage material, the titanium-aluminum composite oxide, and the first activated alumina are loaded with a first active ingredient.

[0068] In one specific embodiment, one or both of the second oxygen storage material and the second activated alumina are loaded with a second active ingredient.

[0069] In one specific embodiment, the total mass ratio of palladium to rhodium in the catalyst is (1-20):2. For example, it can be 9:1, 15:2, 5:1, 5:2, or 1:2.

[0070] In one specific embodiment, the total mass ratio of platinum to rhodium in the catalyst is (1-10):2. For example, it can be 1:2, 3:2, 5:2, or 5:1.

[0071] In one specific embodiment, the total loading of the first active component and the second active component in the catalyst is (0.01~50) g / ft. 3 For example, it can be 2g / ft. 3 10g / ft 3 20g / ft 3 30g / ft 3 40g / ft 3 50g / ft 3 .

[0072] In one specific embodiment, the second active ingredient further includes platinum and / or palladium.

[0073] In one specific embodiment, the content of the first support in the catalyst is 6-9 wt%.

[0074] In one specific embodiment, the content of the second support in the catalyst is 4 to 7 wt%.

[0075] In one specific embodiment, in the first load, the mass ratio of the first oxygen storage material, the first activated alumina, and the titanium-aluminum composite oxide is (20-30):(40-60):(5-10). For example, it can be 28:55:9, 15:50:7, or 10:45:6.

[0076] In one specific embodiment, the mass ratio of the second oxygen storage material to the second activated alumina in the second support is (10-20):(50-70). For example, it can be 15:60, 10:50, or 20:70.

[0077] In one specific embodiment, the specific surface area of ​​the first oxygen storage material and the second oxygen storage material is 100-150 m². 2 / g, pore volume 0.1~0.4cm 3 / g, with a pore size of 10–20 nm.

[0078] In one specific embodiment, the first oxygen storage material comprises a first transition metal oxide, which includes one or more oxides of cerium, zirconium, lanthanum, scandium, and yttrium.

[0079] In a more specific embodiment, based on the mass of the first oxygen storage material, the content of cerium oxide is 10-70 wt%, the content of zirconium oxide is 10-70 wt%, the content of lanthanum oxide is 1-10 wt%, the content of yttrium oxide is 1-10 wt%, and the content of scandium oxide oxide is 1-15 wt%.

[0080] In a more specific embodiment, the first oxygen storage material further includes one or more oxides of praseodymium, neodymium, samarium, and manganese, with a total content of 1 to 10 wt% of the mass of the first oxygen storage material.

[0081] Based on the mass of the first oxygen storage material, the cerium oxide content can be 10wt%, 20wt%, 21wt%, 23wt%, 30wt%, 40wt%, 50wt%, 60wt%, or 70wt%.

[0082] Based on the mass of the first oxygen storage material, the zirconium oxide content can be 20wt%, 30wt%, 40wt%, 48wt%, 50wt%, 60wt%, or 70wt%.

[0083] Based on the mass of the first oxygen storage material, the lanthanum oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, 10 wt%, 12 wt%, or 15 wt%.

[0084] Based on the mass of the oxygen storage material, the scandium oxide content can be 1 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, and 10 wt%.

[0085] Based on the mass of the first oxygen storage material, the yttrium oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, or 10 wt%. Based on the mass of the first oxygen storage material, the praseodymium oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, or 10 wt%.

[0086] Based on the mass of the first oxygen storage material, the neodymium oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, and 10 wt%.

[0087] Based on the mass of the first oxygen storage material, the samarium oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, and 10 wt%.

[0088] Based on the mass of the first oxygen storage material, the manganese oxide content can be 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, and 10 wt%.

[0089] In a more specific embodiment, the first oxygen storage material further includes a first alkaline earth metal oxide.

[0090] In a more specific embodiment, the first alkaline earth metal oxide is selected from one or more of calcium oxide, magnesium oxide, strontium oxide, and barium oxide. The alkaline earth metal oxide serves to improve the stability and oxygen storage / release rate of the oxygen storage material.

[0091] In a more specific embodiment, the content of the first alkaline earth metal oxide in the first oxygen storage material is 0.01–5 wt%. For example, it can be 1 wt%, 2 wt%, 3 wt%, 4 wt%, or 5 wt%.

[0092] In one specific embodiment, the second oxygen storage material comprises a second transition metal oxide, which comprises one or both of oxides of cerium and zirconium.

[0093] In a more specific embodiment, the second transition metal oxide further includes one or more oxides of lanthanum, scandium, yttrium, praseodymium, neodymium, and samarium.

[0094] In a more specific embodiment, based on the mass of the second oxygen storage material, the content of cerium oxide is 10-30 wt% and the content of zirconium oxide is 50-80 wt%.

[0095] Based on the mass of the second oxygen storage material, the cerium oxide content can be 10%, 20%, or 30%.

[0096] Based on the mass of the second oxygen storage material, the zirconium oxide content can be 50%, 60%, 70%, 72%, or 80%.

[0097] In a more specific embodiment, the second transition metal oxide further includes one or more oxides of lanthanum, scandium, yttrium, praseodymium, neodymium, and samarium.

[0098] In a further specific embodiment, the lanthanum oxide content in the second transition metal oxide is 1–10 wt%. Based on the mass of the second oxygen storage material, the lanthanum oxide content can be 1 wt%, 5 wt%, or 10 wt%.

[0099] In a further specific embodiment, the scandium oxide content in the second transition metal oxide is 1 to 10 wt%.

[0100] In a further specific embodiment, the yttrium oxide content in the second transition metal oxide is 1 to 10 wt%. Based on the mass of the second oxygen storage material, the yttrium oxide content can be 1 wt%, 4 wt%, 5 wt%, or 10 wt%.

[0101] In a further specific embodiment, the samarium oxide content in the second transition metal oxide is 1 to 10 wt%.

[0102] In a further specific embodiment, the second oxygen storage material further includes a second alkaline earth metal oxide.

[0103] In a more specific embodiment, the second alkaline earth metal oxide is selected from one or more of calcium oxide, magnesium oxide, strontium oxide, and barium oxide.

[0104] In a more specific embodiment, the content of the second alkaline earth metal oxide in the second oxygen storage material is 0.01–3 wt%. For example, it can be 1 wt%, 2 wt%, or 3 wt%.

[0105] In one specific embodiment, the first activated alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina, and samarium-modified alumina. More preferably, it is lanthanum-modified alumina.

[0106] In one specific embodiment, the second activated alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina, and samarium-modified alumina. Lanthanum-modified alumina is more preferred.

[0107] This invention uses activated alumina to support the coating and improve the activity and stability of the catalyst.

[0108] In one specific embodiment, the activated alumina is γ-alumina.

[0109] In one specific embodiment, the specific surface area of ​​the activated alumina is 100–220 m². 2 / g, pore volume 0.4~0.8cm 3 / g, with a pore size of 5–25 nm.

[0110] In one specific embodiment, the titanium dioxide content, based on the mass of the catalyst, is 0.01 to 1.0 wt%. For example, it can be 0.1 wt%, 0.2 wt%, 0.24 wt%, 0.27 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.57 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, or 1.0 wt%. Preferably, it is 0.24 to 0.3 wt%, more preferably 0.27 wt%.

[0111] In one specific embodiment, the titanium dioxide content in the titanium-aluminum composite oxide is 5-95 wt%, preferably 40-50 wt%.

[0112] In one specific embodiment, the specific surface area of ​​titanium dioxide is 60–100 m². 2 / g, pore volume 0.4~0.8cm 3 / g, with a pore size of 5–25 nm.

[0113] In one specific embodiment, titanium dioxide is selected from anatase.

[0114] In one specific embodiment, the first oxygen storage material is prepared by the following method: mixing the soluble salt solutions of each component in the first oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining.

[0115] In a more specific embodiment, the soluble salt solution includes nitrates, acetates, and sulfates.

[0116] In a more specific embodiment, the alkaline precipitant is ammonia.

[0117] In a more specific embodiment, when preparing the first oxygen storage material, the drying temperature is 50-150°C and the drying time is 4-6 hours; the calcination temperature is 800-1000°C and the calcination time is 2-5 hours.

[0118] In one specific embodiment, the second oxygen storage material is prepared by the following method: mixing the soluble salt solutions of each component in the second oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining.

[0119] In a more specific embodiment, the soluble salt solution includes nitrates, acetates, and sulfates.

[0120] In a more specific embodiment, the alkaline precipitant is ammonia.

[0121] In a more specific embodiment, when preparing the second oxygen storage material, the drying temperature is 50-150°C and the drying time is 4-6 hours; the calcination temperature is 800-1000°C and the calcination time is 2-5 hours.

[0122] In one specific embodiment, the salt solution of the first active ingredient is loaded onto one or more selected from the first oxygen storage material, titanium-aluminum composite oxide, and first activated alumina using an equal-volume impregnation method.

[0123] In one specific embodiment, the salt solution of the second active ingredient is loaded onto one or both of the second oxygen storage material and the second activated alumina using an equal-volume impregnation method.

[0124] In a more specific embodiment, the salt solution includes nitrate, acetate, and sulfate solutions.

[0125] In a more specific embodiment, after the active ingredient is loaded, it also needs to be dried at a temperature of 50–150°C for 4–6 hours.

[0126] In one specific embodiment, the titanium-aluminum composite oxide is prepared by mixing titanium dioxide with aluminum sol and then drying and calcining it.

[0127] In a more specific embodiment, the titanium-aluminum composite oxide is prepared at a drying temperature of 80-100°C for 3-5 hours.

[0128] In a more specific embodiment, the titanium-aluminum composite oxide is prepared by calcining at a temperature of 400-600°C for a time of 4-6 hours.

[0129] This invention also discloses a method for preparing the catalyst, the method of which is as follows:

[0130] A first slurry is provided, the first slurry is coated onto the carrier, and then calcined;

[0131] A second slurry is provided, which is then further coated onto the carrier, followed by further calcination.

[0132] The first slurry is formed by mixing powder formed from a first load body, a first binder, and water;

[0133] The second slurry is formed by mixing the powder formed from the second load body, the second binder, and water.

[0134] In one specific embodiment, the catalyst preparation process includes a drying treatment before calcination, with a drying temperature of 100-120℃ and a drying time of 3-6 hours.

[0135] In one specific embodiment, during the catalyst preparation process, the calcination temperature is 500-600℃ and the calcination time is 2-3 hours.

[0136] In a more specific embodiment, the solid content of the first slurry is 32-38%.

[0137] In a more specific embodiment, the particle size of the powder formed by the first support is 3-12 μm.

[0138] In a more specific embodiment, the first binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose, and polyvinyl alcohol.

[0139] The use of binders allows the coating powder to be better applied to the carrier, enhancing the strength of the coating and giving the catalyst better stability.

[0140] In a more specific embodiment, the mass of the first binder accounts for 3 to 10 wt% of the mass of the powder formed by the first support.

[0141] In a more specific embodiment, the solid content of the second slurry is 30-35%.

[0142] In a more specific embodiment, the particle size of the powder formed by the second support is 3-11 μm.

[0143] In a more specific embodiment, the second binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose, and polyvinyl alcohol.

[0144] In a more specific embodiment, the mass of the second binder accounts for 3 to 10% of the mass of the second load powder.

[0145] The present invention also discloses the use of the catalyst as an exhaust gas purification catalyst.

[0146] The present invention will now provide more specific embodiments for further explanation.

[0147] In the following examples and comparative examples, the carrier is a cylindrical cordierite ceramic honeycomb carrier with the following dimensions: end face diameter 118.4 mm, length 152.4 mm, mesh number 400, and wall thickness 4.5 mils.

[0148] Example 1

[0149] This embodiment provides a specific method for preparing a catalyst, with the following steps. The total loading of noble metals is 30 g / ft. 3The mass ratio of Pt, Pd, and Rh is 8:15:2, denoted as Pt / Pd / Rh = 8 / 15 / 2.

[0150] (1) Preparation of oxygen storage materials:

[0151] The oxygen storage material of the first support P1 contains the transition metal oxide CeO 2、 ZrO 2、 La2O 3、 Y2O 3、 The contents of Sc2O3 were 40%, 50%, 4%, 2%, and 4%, respectively.

[0152] The transition metal oxides in the oxygen storage material P1 are denoted as CeO2(40)-ZrO2(50)-La2O3(4)-Y2O3(2)-Sc2O3(4). Similarly, the transition metal oxides in the oxygen storage material of the second support P2 are denoted as CeO2(20)-ZrO2(70)-La2O3(5)-Y2O3(5).

[0153] The nitrate solution of each oxide in the oxygen storage material is mixed with the alkaline precipitant ammonia water, the pH of the solution is adjusted to 8-10, filtered, and the precipitate is dried in air at 120°C for 5 hours, and then calcined in air at 900°C for 4 hours to obtain the oxygen storage material.

[0154] (2) Preparation of titanium-aluminum composite oxide: The content of TiO2 in the catalyst is 0.24 wt%.

[0155] Aluminum sol was mixed with titanium dioxide and dried at 80°C for 5 hours, followed by calcination at 400°C for 6 hours. The titanium dioxide content in the titanium-aluminum composite oxide was 40 wt%.

[0156] (3) Active ingredient loading

[0157] Pd and Pt are used as the first active components. Palladium nitrate and platinum nitrate solutions are used to impregnate the active alumina and oxygen storage material in equal volumes, respectively. The mixture is stirred for 1 hour and then dried at 120°C for 5 hours to obtain Pd-loaded active alumina and Pt-loaded oxygen storage material.

[0158] Rh was used as the second active ingredient. The oxygen storage material was impregnated with an equal volume of rhodium nitrate solution, stirred for 1 hour, and then dried at 120°C for 5 hours to obtain the Rh-loaded oxygen storage material.

[0159] (4) Preparation of coating

[0160] 1) Preparation of the first support: The titanium-aluminum composite oxide, the first activated alumina loaded with Pd, and the first oxygen storage material loaded with Pt prepared above were mixed with water and dried at 120°C for 5 hours to obtain the powder of the first support. The powder of the first support was ball-milled with boehmite and water to obtain the first slurry. The first slurry was coated on a carrier, dried at 120°C for 5 hours, and calcined at 550°C for 2 hours to obtain the first support.

[0161] On the first load, the mass ratio of the first oxygen storage material, the first activated alumina, and the titanium-aluminum composite oxide is 28:55:9.

[0162] The mass of the binder, boehmite, is 5% of the mass of the first load powder. The particle size of the first load powder is 8 μm, and the solid content of the first slurry is 36%.

[0163] 2) Preparation of the second support: The second oxygen storage material loaded with Rh prepared above, the second activated alumina, pseudoboehmite, and water are used to prepare the second support using the first support preparation method described above.

[0164] On the second support, the mass ratio of the second oxygen storage material to the second activated alumina is 15:60.

[0165] The mass of the pseudoboehmite is 5% of the mass of the powder of the second support, the particle size of the powder of the second support is 7 μm, and the solid content of the second slurry is 34%.

[0166] In the catalyst, the content of the first support is 7.45 wt%, and the content of the second support is 5.31 wt%.

[0167] Example 2

[0168] This embodiment provides a specific catalyst and its preparation method.

[0169] The preparation method is basically the same as that in Example 1, except that:

[0170] In step (1), the first transition metal oxide in the P1 oxygen storage material is CeO2(40)-ZrO2(50)-La2O3(4)-Y2O3(2)-Nd2O3(4);

[0171] In step (2), the TiO2 content in the Al2O3-TiO2 composite support is 45wt%, and the TiO2 content in the catalyst is 0.27wt%.

[0172] Example 3

[0173] This embodiment provides a specific catalyst and its preparation method.

[0174] The preparation method is basically the same as that in Example 1, except that:

[0175] In step (1), the first transition metal oxide in the P1 oxygen storage material is...

[0176] CeO2(40)-ZrO2(50)-La2O3(4)-Y2O3(2)-Pr6O 11 (4),

[0177] The second transition metal oxide in the P2 oxygen storage material is CeO2(23)-ZrO2(62)-La2O3(3)-Y2O3(12);

[0178] In step (2), the TiO2 content in the Al2O3-TiO2 composite support is 5 wt%, and the TiO2 content in the catalyst is 0.03 wt%.

[0179] Example 4

[0180] This embodiment provides a specific catalyst and its preparation method.

[0181] The preparation method is basically the same as that in Example 1, except that:

[0182] In step (1), the first transition metal oxide in the P1 oxygen storage material is...

[0183] CeO2(40)-ZrO2(50)-La2O3(4)-Y2O3(2)-Nd2O3(4),

[0184] The second transition metal oxide in the P2 oxygen storage material is CeO2(21)-ZrO2(72)-La2O3(2)-Y2O3(5);

[0185] In step (2), the TiO2 content in the Al2O3-TiO2 composite support is 95 wt%, and the TiO2 content in the catalyst is 0.57 wt%.

[0186] In step (3), Pd is used as the first active component. The active alumina, titanium-aluminum composite oxide and oxygen storage material are impregnated with an equal volume of palladium nitrate solution to obtain Pd-loaded active alumina, Pd-loaded oxygen storage material and Pd-loaded titanium-aluminum composite oxide.

[0187] Pt and Rh were used as the second active components. Platinum nitrate and rhodium nitrate solutions were used to impregnate the active alumina and oxygen storage material in equal volumes, respectively, to obtain Pt-loaded active alumina and Rh-loaded oxygen storage material.

[0188] Example 5

[0189] This embodiment provides a specific catalyst and its preparation method. The total loading of noble metals is 30 g / ft. 3 , Pt / Pd / Rh=8 / 15 / 2.

[0190] The preparation method is basically the same as that in Example 1, except that:

[0191] In step (2), the TiO2 content in the catalyst is 45 wt%, and the TiO2 content in the catalyst is 0.27 wt%.

[0192] Example 6

[0193] This embodiment provides a specific catalyst and its preparation method.

[0194] The preparation method is basically the same as that in Example 1, except that:

[0195] In step (2), the TiO2 content in the Al2O3-TiO2 composite support is 50 wt%, and the TiO2 content in the catalyst is 0.3 wt%.

[0196] Example 7

[0197] This embodiment provides a specific catalyst and its preparation method. The total loading of noble metals is 30 g / ft. 3 , Pt / Pd / Rh=8 / 15 / 2.

[0198] The preparation method is basically the same as that in Example 5, except that:

[0199] In step (3), Pd is used as the first active component. The active alumina, titanium-aluminum composite oxide and oxygen storage material are impregnated with an equal volume of palladium nitrate solution to obtain Pd-loaded active alumina and Pd-loaded oxygen storage material, which are Pd-loaded titanium-aluminum composite oxides.

[0200] Pt and Rh are used as the second active components. Platinum nitrate and rhodium nitrate solutions are used to impregnate the active alumina and oxygen storage material in equal volumes to obtain Pt-loaded active alumina and Rh-loaded oxygen storage material.

[0201] Example 8

[0202] This embodiment provides a specific catalyst and its preparation method.

[0203] The preparation method is basically the same as that in Example 5, except that the total loading of precious metals is 30 g / ft. 3 , Pt / Pd / Rh=0 / 23 / 2.

[0204] In step (3), Pd is used as the first active component. The active alumina, titanium-aluminum composite oxide and oxygen storage material are impregnated with an equal volume of palladium nitrate solution to obtain Pd-loaded active alumina and Pd-loaded oxygen storage material, which are Pd-loaded titanium-aluminum composite oxides.

[0205] Example 9

[0206] This embodiment provides a specific catalyst and its preparation method.

[0207] The preparation method is basically the same as that in Example 5, except that the total loading of precious metals is 30 g / ft. 3 , Pt / Pd / Rh=23 / 0 / 2.

[0208] In step (3), Pt is used as the first active component. Platinum nitrate solution is used to impregnate active alumina powder, titanium-aluminum composite oxide and oxygen storage material in equal volume. The active alumina loaded with Pt, the oxygen storage material loaded with Pt, and the titanium-aluminum composite oxide loaded with Pt are all impregnated.

[0209] Example 10

[0210] This embodiment provides a specific catalyst and its preparation method.

[0211] The preparation method is basically the same as that in Example 7, except that the total loading of precious metals is 20 g / ft. 3 , Pt / Pd / Rh=8 / 15 / 2.

[0212] Example 11

[0213] This embodiment provides a specific catalyst and its preparation method.

[0214] The preparation method is basically the same as that in Example 7, except that the total loading of precious metals is 2 g / ft. 3 , Pt / Pd / Rh=8 / 15 / 2.

[0215] Example 12

[0216] This embodiment provides a specific catalyst and its preparation method.

[0217] The preparation method is basically the same as that in Example 2, except that the oxygen storage material of P1 is CeO2(40)-ZrO2(50)-La2O3(5)-Y2O3(5).

[0218] Example 13

[0219] This embodiment provides a specific catalyst and its preparation method.

[0220] The preparation method is basically the same as that in Example 12, except that in step (1), the oxygen storage material P1 is Sc2O3.

[0221] Example 14

[0222] This embodiment provides a specific catalyst and its preparation method.

[0223] The preparation method is basically the same as that in Example 8, except that both P1 and P2 oxygen storage materials contain alkaline earth metal BaO. The oxygen storage material of P1 is CeO2(40)-ZrO2(48)-La2O3(4)-Y2O3(2)-Sc2O3(4)-BaO(2), and the oxygen storage material of P2 is CeO2(20)-ZrO2(70)-La2O3(5)-Y2O3(4)-BaO(1).

[0224] Comparative Example 1

[0225] This comparative example provides a commercially available three-way catalytic converter for gasoline vehicles. The precious metal content of the catalytic converter coating was tested using ICP (inductively coupled plasma mass spectrometry). The precious metals were palladium and rhodium, with a palladium-to-rhodium mass ratio of approximately 10:1, and an average precious metal content of 30 g / ft. 3 The composition of the coating material of the three-way catalyst for gasoline vehicles was tested using EDS (energy dispersive spectroscopy). The main components are cerium, zirconium and aluminum. The oxides of these three components account for more than 85% of the total content. In addition, it also contains small amounts of barium, yttrium and lanthanum.

[0226] Comparative Example 2

[0227] This comparative example is the comparative example of Example 1. The only difference is:

[0228] In step (1), the first transition metal oxide in the P1 oxygen storage material is CeO2(40)-ZrO2(50)-La2O3(5)-Y2O3(5); excluding the titanium-aluminum composite oxide in step (2).

[0229] Comparative Example 3

[0230] This comparative example is the comparative example of Example 6. The only difference is:

[0231] The preparation method is basically the same as that in Example 6, except that it does not contain titanium-aluminum composite oxide.

[0232] Comparative Example 4

[0233] This comparative example uses the technical solution of invention patent CN102008958B to prepare the catalyst. The support is a cylindrical cordierite ceramic support with the following dimensions: end face diameter 118.4 mm, length 152.4 mm, mesh count 400, and wall thickness 4.5 mils. The total loading of precious metals is 30 g / ft. 3 , Pt / Pd / Rh=8 / 15 / 2.

[0234] The preparation method is as follows.

[0235] (1) Preparation of the first slurry

[0236] The nitrates of rare earth metal La, alkaline earth metal Ba, transition metal Mn, noble metals Pt and Pd, along with boehmite, activated alumina, rare earth oxides (CeO2(50)-ZrO2(50)) and deionized water, were mixed in a certain proportion. The mixture was ball-milled to obtain a first slurry, which was then stored in the slurry storage container of a special catalyst coating device. The first slurry had a solid content of 35 wt%, and the mass ratio of each component was: boehmite: activated alumina: rare earth oxides: rare earth metals: alkaline earth metals: transition metals = 13:50:23:2:3:1.

[0237] (2) Preparation of the first support

[0238] The support was placed on a catalyst coating apparatus and coated with a first slurry. After coating, the first slurry was dried at 120°C for 5 hours, and then calcined at 550°C for 2 hours to obtain the first supported catalyst. The content of the first supported catalyst in the catalyst was 7.48 wt%.

[0239] (3) Preparation of the second slurry

[0240] The nitrates of rare earth metal La, alkaline earth metal Ba, transition metal Mn, and noble metal Rh, along with boehmite, activated alumina, rare earth oxides (CeO2(20)-ZrO2(80)) and deionized water, are mixed in a certain proportion. The mixture is ball-milled to obtain a second slurry. The second slurry is stored in the slurry storage container of the catalyst coating device. The solid content of the second slurry is 32wt%, and the mass ratio of each component is: boehmite: activated alumina: rare earth oxides: rare earth metals: alkaline earth metals: transition metals = 13:50:23:2:3:1.

[0241] (4) Preparation of the second support

[0242] The support containing the first support prepared in step (2) is placed on a catalyst coating device and coated with a second slurry. After the second slurry is coated, it is dried at 120°C for 5 hours and then calcined at 550°C for 2 hours to obtain a three-way catalyst for purifying gasoline vehicle exhaust. The content of the second support in the catalyst is 5.29 wt%.

[0243] The catalysts prepared in Examples 1-14 and Comparative Examples 1-4 were subjected to catalytic activity evaluation and stability tests. The tests were conducted on a low-carbon alcohol fuel vehicle exhaust gas simulation test apparatus. The test results are shown in Tables 1 and 2, respectively. The simulated atmosphere composition was: 2500 ppm CH3OH / CH3CH2OH; 200 ppm CH2O / CH3CHO; 200 ppm CH2O2 / CH3COOH; 0.75% CO; 800 ppm NO; 0.6% O2; 8% CO2; 16% H2O; and N2 as the balance gas. The space velocity was 60000 h⁻¹. -1 .

[0244] Catalytic activity test method: The catalysts prepared in Examples 1-14 and Comparative Examples 1-4 were placed in a simulated atmosphere, heated to 550°C, and activated at a constant temperature for 2 hours. Then, the temperature was cooled to room temperature. After the temperature stabilized, the temperature was increased to 650°C at a rate of 10°C / min. During the heating process, the concentrations of low carbon alcohols, low carbon aldehydes, low carbonic acid, CO, and NO were detected after the catalyst reaction. The conversion efficiency and ignition temperature were calculated.

[0245] Stability testing method: The catalysts prepared in Examples 1-14 and Comparative Examples 1-4 were subjected to hydrothermal aging treatment at 850℃ for 40 hours. The gas mixture for hydrothermal aging was H2O = 16%, with the remainder being dry air. The catalysts after hydrothermal aging were then subjected to the above-mentioned catalytic activity test, the conversion efficiency was calculated, and the ignition temperatures T50 and T90 were tested. The ignition temperature T50 is the catalyst temperature at which the conversion rate reaches 50%, and the ignition temperature T90 is the catalyst temperature at which the conversion rate reaches 90%.

[0246] Table 1 Catalyst process parameters for Examples 1-14

[0247]

[0248] Table 2 Catalyst process parameters for Comparative Examples 1-4

[0249]

[0250]

[0251] Table 3 Ignition temperature and conversion rate of fresh catalyst

[0252]

[0253]

[0254]

[0255] Table 4 Ignition temperature and conversion rate of hydrothermally aged catalysts

[0256]

[0257]

[0258]

[0259] As can be seen from Tables 1-4 above,

[0260] Comparative studies of Examples 5 and 12 show that adding Sc2O3 to the oxygen storage material of P1 can significantly improve the activity and stability of the catalyst. Introducing scandium ions into the oxygen storage material can prevent the decline in oxygen storage performance caused by cerium oxide grain growth during calcination, thereby preventing a decrease in catalyst activity and stability. Comparative studies of Examples 2 and 5 show that Sc2O3 (scandium oxide) significantly improves the conversion rate of low-carbon alcohols, low-carbon aldehydes, and low-carbon carbonates compared to Nd2O3 (neodymium oxide), and also exhibits better catalyst stability.

[0261] Comparative studies of Examples 5, 12, and 13 reveal that the synergistic effect of Sc2O3 (scandium oxide) with other transition metal oxides in the oxygen storage material can further improve the stability of the catalyst and the conversion rate of low-carbon alcohols, low-carbon aldehydes, and low-carbon carbonates.

[0262] Comparing Example 5 and Comparative Example 3, it can be found that TiO2 (titanium dioxide) can improve the conversion rate of CO, lower alcohols, lower aldehydes, and lower carbonic acid by the catalyst. A certain proportion of Ti... 4+ TiO2 readily reacts with adsorbed CO, increasing the conversion rate of CO. Furthermore, TiO2 can accelerate the transfer of adsorbed oxygen, further promoting the oxidation reaction of lower alcohols and the like.

[0263] By comparing Examples 1 and 5-6, it can be found that the content of TiO2 (titanium dioxide) needs to be precisely controlled. When the TiO2 content is 0.27%, the catalyst has the highest conversion rate of low-carbon alcohols. When the TiO2 content is too low or too high, the conversion rate of low-carbon alcohols is relatively low.

[0264] Comparing Examples 5 and 7-9 reveals that Pd, Pt, and Rh exhibit different catalytic activities for lower alcohols, lower aldehydes, lower carbonic acids, CO, and NO, with Pt showing the lowest catalytic activity. The distribution of noble metals affects catalyst activity; the catalyst achieves the best conversion rates for lower alcohols, lower aldehydes, lower carbonic acids, CO, and NO when Pd is located in the first support and Rh in the second support, followed by Pt in the second support.

[0265] By comparing Examples 7, 10 and 11, it can be found that the more precious metals are added to the catalyst, the better the catalyst activity.

[0266] By comparing Examples 8 and 14, it can be found that the alkaline earth metal of the oxygen storage material can improve the conversion rate of pollutants by the catalyst and improve the stability of the catalyst to a certain extent.

[0267] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A catalyst, characterized in that, The catalyst includes a support, on which a first support and a second support are loaded; the first support comprises a first oxygen storage material, a titanium-aluminum composite oxide, and a first activated alumina, and a first active ingredient is loaded on the first support; the second support comprises a second oxygen storage material and a second activated alumina, and a second active ingredient is loaded on the second support; the first active ingredient is platinum and / or palladium; the second active ingredient includes rhodium; the content of the first support in the catalyst is 6-9 wt%; the content of the second support in the catalyst is 4-7 wt%; in the first support, the first oxygen storage material, the first activated alumina, the titanium-aluminum composite oxide, and the second active ingredient are loaded on the second support; the first active ingredient is platinum and / or palladium; the second active ingredient includes rhodium; the catalyst contains 6-9 wt% of the first support; the catalyst contains 4-7 wt% of the second support; ... active ingredient, the first oxygen storage material, the first activated alumina, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active ingredient, the first active The mass ratio of the compounds is (20-30):(40-60):(5-10); in the second support, the mass ratio of the second oxygen storage material to the second activated alumina is (10-20):(50-70); the first oxygen storage material includes a first transition metal oxide, which includes one or more oxides of cerium, zirconium, lanthanum, scandium, and yttrium; and / or, the second oxygen storage material includes a second transition metal oxide, which includes one or two oxides of cerium and zirconium; based on the mass of the catalyst, the titanium dioxide content in the titanium-aluminum composite oxide is 0.24~0.3wt%.

2. The catalyst according to claim 1, characterized in that, The carrier is selected from one or both of cordierite ceramic honeycomb carrier and metal honeycomb carrier; And / or, one or more of the first oxygen storage material, the titanium-aluminum composite oxide, and the first activated alumina are loaded with a first active ingredient; And / or, one or both of the second oxygen storage material and the second activated alumina are loaded with a second active ingredient; And / or, in the catalyst, the total mass ratio of palladium to rhodium is (1~20):2; And / or, in the catalyst, the total mass ratio of platinum to rhodium is (1~10):2; And / or, the second active ingredient further includes platinum and / or palladium; And / or, in the catalyst, the total loading of the first active component and the second active component is (0.01~50) g / ft. 3 .

3. The catalyst according to claim 1, characterized in that, The first active alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina, and samarium-modified alumina; And / or, the second active alumina is selected from one or more of lanthanum-modified alumina, yttrium-modified alumina, neodymium-modified alumina, praseodymium-modified alumina and samarium-modified alumina.

4. The catalyst according to claim 3, characterized in that, Based on the mass of the first oxygen storage material, the content of cerium oxide is 10-70 wt%, the content of zirconium oxide is 10-70 wt%, the content of lanthanum oxide is 1-10 wt%, the content of yttrium oxide is 1-10 wt%, and the content of scandium oxide oxide is 1-15 wt%. And / or, based on the mass of the second oxygen storage material, the cerium oxide content is 10-30 wt%, and the zirconium oxide content is 50-80 wt%; And / or, the first transition metal oxide further includes one or more oxides of praseodymium, neodymium, samarium, and manganese; And / or, the second transition metal oxide further includes one or more oxides of lanthanum, scandium, yttrium, praseodymium, neodymium, and samarium; And / or, the first oxygen storage material further includes a first alkaline earth metal oxide; And / or, the second oxygen storage material further includes a second alkaline earth metal oxide.

5. The catalyst according to claim 4, characterized in that, The content of the first alkaline earth metal oxide in the first oxygen storage material is 0.01~3wt%; And / or, the content of the second alkaline earth metal oxide in the second oxygen storage material is 0.01~5wt%.

6. The catalyst according to claim 1, characterized in that, The first oxygen storage material is prepared by the following method: soluble salt solutions of each component in the first oxygen storage material are mixed with an alkaline precipitant, the pH of the solution is adjusted to 8-10, filtered, dried, and calcined. And / or, the second oxygen storage material is prepared by the following method: mixing a soluble salt solution of each component in the second oxygen storage material with an alkaline precipitant, adjusting the pH of the solution to 8-10, filtering, drying, and calcining; And / or, the salt solution of the first active ingredient is loaded onto one or more selected from the first oxygen storage material, titanium-aluminum composite oxide and first activated alumina using an equal-volume impregnation method; And / or, the salt solution of the second active ingredient is loaded onto one or both of the second oxygen storage material and the second activated alumina using an equal-volume impregnation method.

7. A method for preparing a catalyst according to any one of claims 1 to 6, characterized in that, A first slurry is provided, the first slurry is coated onto the carrier, and then calcined; A second slurry is provided, which is then further coated onto the carrier, followed by further calcination. The first slurry is formed by mixing powder formed from a first load body, a first binder, and water; The second slurry is formed by mixing the powder formed from the second load body, the second binder, and water.

8. The preparation method according to claim 7, characterized in that, The solid content of the first slurry is 32~38 wt%; And / or, the particle size of the powder formed by the first support is 3-12 μm; And / or, the solid content of the second slurry is 30~35wt%; And / or, the particle size of the powder formed by the second support is 3-11 μm.

9. The preparation method according to claim 7, characterized in that, The first binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose, and polyvinyl alcohol; And / or, the mass of the first binder accounts for 3 to 10 wt% of the mass of the powder formed by the first support body; And / or, the second binder is selected from one or more of boehmite, aluminum sol, silica sol, attapulgite, cellulose and polyvinyl alcohol; And / or, the mass of the second binder accounts for 3 to 10 wt% of the mass of the powder formed by the second load.

10. Use of the catalyst according to any one of claims 1 to 6 or the catalyst prepared by any one of claims 7 to 9 as a catalyst for exhaust gas from low-carbon alcohol fuel vehicles.

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