Catalysts for the removal of volatile organic compounds, their preparation methods and applications

Abstract

This invention relates to the field of catalyst preparation, disclosing a catalyst for the removal of volatile organic compounds (VOCs), its preparation method, and its applications. The catalyst comprises a support and an active component supported on the support; wherein the active component comprises a noble metal and a matrix metal oxide, wherein the noble metal is Pt metal and / or Ag-Pt alloy; the matrix metal oxide comprises single and / or composite oxides of Al and Ce, rare earth element oxides other than cerium, and zinc oxide. The catalyst provided by this invention has high efficiency in catalytic oxidation of VOCs and is expected to be widely applied in the preparation of various fixed-bed catalytic materials, showing broad application prospects.

Description

Technical Field

[0001] This invention relates to the field of catalyst preparation, specifically to a catalyst for the removal of volatile organic compounds, a method for preparing the catalyst, and the application of the catalyst in the catalytic oxidation of VOCs. Background Technology

[0002] Volatile organic compounds (VOCs) are substances with boiling points between 50-260℃ and saturated vapor pressures above 133.3 Pa at room temperature. They include hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, aldehydes, ketones, and polycyclic aromatic hydrocarbons. VOCs are major pollutants emitted during the production and processing of various industries such as petrochemicals, printing, and pharmaceuticals. These substances have a strong odor, irritate or damage human organs, and in severe cases, can cause poisoning or cancer, endangering human health. Furthermore, VOCs in the atmosphere can also cause problems such as photochemical smog, seriously damaging the ecological environment.

[0003] Based on principles, VOCs pollution control can be categorized into adsorption, incineration, catalytic oxidation, biological methods, and membrane separation. Among these, catalytic oxidation technology, with its advantages of cost-effectiveness and high efficiency, is one of the most promising technologies for VOCs removal. Developing high-performance catalytic oxidation catalysts is crucial for achieving waste gas purification and green production. Currently, catalytic oxidation catalysts often use honeycomb inert materials (such as cordierite) as supports, loading active components with low-temperature oxidation properties to achieve VOCs catalytic oxidation. VOCs catalytic oxidation catalysts typically use precious metals such as platinum and palladium as active components. For example, CN201811568947 discloses an oxidation catalyst for catalytic combustion of VOCs and its preparation method, which involves coating the surface of a cordierite honeycomb ceramic support with a precious metal Pt active component. This catalyst can achieve complete toluene conversion below 250℃. Although platinum and palladium exhibit excellent oxidation performance, they are expensive, accounting for over 60% of the total catalyst cost; while non-precious metal catalysts have poor activity and stability, resulting in low market acceptance. How to improve the low-temperature oxidation performance of catalysts while keeping costs low is a pressing issue in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a catalyst that can improve the low-temperature catalytic oxidation performance of VOCs while keeping costs low. Specifically, it provides a catalyst for the removal of volatile organic compounds, a method for its preparation, and the application of the catalyst in the catalytic oxidation of VOCs. The catalyst of this invention has low cost and low catalytic temperature, and can achieve the catalytic oxidation of VOCs at high space velocity and low temperature.

[0005] To achieve the above objectives, a first aspect of the present invention provides a catalyst for the removal of volatile organic compounds, the catalyst comprising a support and an active component supported on the support;

[0006] The active component comprises a noble metal and a matrix metal oxide, wherein the noble metal is Pt metal and / or Ag-Pt alloy; the matrix metal oxide comprises single and / or composite oxides of Al and Ce, oxides of rare earth elements other than cerium, and zinc oxide.

[0007] Preferably, the Ag-Pt alloy has a particle size of less than 10 nm.

[0008] Preferably, the single and / or composite oxides of Al and Ce comprise Al-Ce composite oxides.

[0009] A second aspect of the present invention provides a method for preparing a catalyst for the removal of volatile organic compounds, the method comprising:

[0010] (1) A noble metal colloidal solution is prepared by first mixing the precursor of the noble metal, the reducing agent, the stabilizer and water.

[0011] (2) The mixture of the matrix metal oxide precursor and the noble metal colloidal solution are mixed for a second time to obtain the catalyst slurry;

[0012] (3) The catalyst slurry is coated on the surface of the support and subjected to a first drying and ozone calcination treatment to obtain the catalyst loaded with active components.

[0013] Among them, the precious metal is a combination of Pt and Ag or Pt;

[0014] The matrix metal oxide comprises single and / or composite oxides of Al and Ce, oxides of rare earth elements other than cerium, and zinc oxide.

[0015] Preferably, in step (2), when the single and / or composite oxides of Al and Ce contain Al-Ce composite oxides, the method for preparing the mixture of matrix metal oxide precursors includes: preparing Al-Ce composite oxides, and then mixing Al-Ce composite oxides, precursors of rare earth element oxides other than cerium, zinc oxide precursors and water in a third mixing process to obtain the mixture of matrix metal oxide precursors.

[0016] A third aspect of the present invention provides a catalyst prepared according to the method described above.

[0017] The fourth aspect of the present invention relates to the application of the VOCs oxidation catalyst described above in the catalytic oxidation of VOCs.

[0018] The catalyst provided by this invention exhibits superior performance in catalytic oxidation of VOCs compared to commercial platinum-based catalysts, and is also less expensive. In particular, the preferred use of an Ag-Pt alloy further reduces the amount of Pt required, significantly lowering the catalyst cost while simultaneously improving its catalytic performance.

[0019] Under the preferred conditions of this invention, when Al-Ce composite oxide is used as one of the active components in combination with other components, the catalytic performance of the catalyst can be further improved.

[0020] The preparation method provided in this invention obtains Pt metal or Ag-Pt alloys through liquid-phase reduction, achieving tight coupling of the two noble metals and enhancing synergistic effects. The reducing agent and stabilizer used are inexpensive, readily available, and have low toxicity. Furthermore, the Ag / Pt ratio in the alloy phase can be flexibly adjusted, resulting in Ag-Pt alloy active centers with excellent performance. Compared to Pt-based catalysts, Ag-Pt alloy catalysts exhibit improved catalytic oxidation performance when loaded with the same weight of noble metal, while reducing catalyst costs.

[0021] The preparation method provided in this invention achieves redispersion of precious metals through high-temperature ozone roasting, thereby improving the utilization efficiency of precious metals.

[0022] The preparation method provided in this invention is simple to operate, suitable for mass production, and is expected to be extended to the preparation of various fixed-bed catalytic materials, showing broad application prospects. Attached Figure Description

[0023] Figure 1 This is a TEM image of the carrier coated with catalyst slurry in Example 1 after drying.

[0024] Figure 2 This is a TEM image of the carrier coated with catalyst slurry in Example 1 after drying and ozone calcination. Detailed Implementation

[0025] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0026] A first aspect of the present invention provides a catalyst for the removal of volatile organic compounds, the catalyst comprising a support and an active component supported on the support;

[0027] The active component comprises a noble metal and a matrix metal oxide, wherein the noble metal is Pt metal and / or Ag-Pt alloy; the matrix metal oxide comprises single and / or composite oxides of Al and Ce, oxides of rare earth elements other than cerium, and zinc oxide.

[0028] In this invention, "Pt metal and / or Ag-Pt alloy" means that the noble metal in the active component exists in the form of elemental Pt metal and / or Ag-Pt alloy. The inventors of this invention discovered during their research that when the noble metal exists in the form of an Ag-Pt alloy, the catalytic performance of the catalyst can be further improved. Preferably, the noble metal comprises an Ag-Pt alloy.

[0029] Preferably, the Ag-Pt alloy has a particle size of less than 10 nm, such as 1, 2, 3, 4, 5, 6, 7, 8, 9 nm or any range between any two values, more preferably 1-8 nm.

[0030] In this invention, single and / or composite oxides of Al and Ce refer to combinations of single oxides of Al and Ce and / or composite oxides of Al and Ce. Specifically, combinations of single oxides of Al and Ce refer to combinations of aluminum oxide and cerium oxide. Composite oxides of Al and Ce can be, for example, composed of Al... x Ce y O z The chemical formula is represented by 3x + 4y = 2z. Preferably, the single and / or composite oxides of Al and Ce comprise Al-Ce composite oxides.

[0031] In this invention, rare earth element oxides other than cerium refer to oxides of rare earth elements other than cerium. For example, rare earth elements other than cerium are selected from at least one of La, Pr and Y, preferably La. Rare earth element oxides other than cerium are selected from at least one of lanthanum oxide, praseodymium oxide and yttrium oxide.

[0032] The loading of the active component can be selected within a wide range. Preferably, based on the volume of the carrier, the total loading of the active component is 10-200 g / L, such as 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200 g / L and any range between any two values, preferably 40-160 g / L.

[0033] Preferably, based on the volume of the carrier, the loading of precious metal is 0.1-10 g / L, for example, it can be 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 4, 6, 8, 10 g / L and any range between any two values, preferably 0.3-7 g / L.

[0034] When the precious metal comprises an Ag-Pt alloy, preferably, based on the volume of the carrier, the Ag loading is 0.2-4 g / L, for example, it can be 0.2, 0.4, 0.6, 0.8, 1, 2, 3, 4 g / L or any range between any two values, more preferably 0.4-2 g / L; the Pt loading is 0.1-3 g / L, for example, it can be 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 3 g / L or any range between any two values, more preferably 0.2-1 g / L.

[0035] Preferably, the weight ratio of Ag to Pt in the precious metal is 0.1-4:1, such as 0.1:1, 0.2:1, 0.4:1, 0.6:1, 0.8:1, 1:1, 2:1, 3:1, 4:1, and any range between any two values, more preferably 0.5-2.5:1.

[0036] Preferably, based on the volume of the support, the loading of single and / or composite oxides of Al and Ce is 30-120 g / L, for example, it can be 30, 40, 60, 80, 100, 120 g / L and any range between any two values, more preferably 60-95 g / L.

[0037] Preferably, the molar ratio of aluminum to cerium is 1-10:1, such as 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, and any range between any two values, more preferably 4-8:1.

[0038] Preferably, based on the volume of the carrier, the loading of rare earth element oxides other than cerium is 6-15 g / L, for example, it can be 6, 8, 10, 12, 14, 15 g / L and any range between any two values, more preferably 7-12 g / L.

[0039] When the rare earth element other than cerium is selected from at least one of La, Pr, and Y, preferably, the loading of lanthanum oxide is 0-15 g / L, more preferably 7-12 g / L, based on the volume of the support. Preferably, the loading of praseodymium oxide is 0-5 g / L, more preferably 1-3 g / L, based on the volume of the support. Preferably, the loading of yttrium oxide is 0-15 g / L, more preferably 7-12 g / L, based on the volume of the support.

[0040] Preferably, the zinc oxide loading is 2-12 g / L based on the volume of the carrier, for example, it can be 2, 4, 6, 8, 10, 12 g / L or any range between any two values, preferably 4-10 g / L.

[0041] The present invention has a wide range of choices for the carrier, and can be any carrier commonly used in the field. The present invention does not have any particular limitation on this. For example, the carrier can be an inorganic oxide carrier.

[0042] Preferably, the carrier is a carrier with a regular structure. That is, the carrier has a regular structure in appearance, which facilitates assembly, and the pore structure of the carrier can also be regular.

[0043] Preferably, the pore density of the cross-section of the regular structure carrier is 50-400 pores / square inch, for example, it can be 50, 100, 150, 200, 250, 300, 350, 400 pores / square inch or any range between any two values.

[0044] Preferably, the carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

[0045] In a preferred embodiment, the cross-sectional area of ​​each hole in the carrier is 0.4-10 square millimeters, preferably 0.4-4 square millimeters.

[0046] In a preferred embodiment, the porosity of the carrier's cross-section is 20-80%, more preferably 50-80%.

[0047] The holes can be regular or irregular in shape. The shapes of the holes can be the same or different. Each hole can be one of the following: square, equilateral triangle, regular hexagon, circle, and corrugated.

[0048] The support described in this invention can be used in the catalyst bed provided in a fixed-bed reactor. The support can be a monolithic block with an internally formed hollow channel structure. Active components can be distributed on the inner and / or outer walls of the channels, and the channel space can serve as a flow space for fluids. The support can also be a regular support with a honeycomb-like opening in its cross-section (referred to as a honeycomb support).

[0049] A second aspect of the present invention provides a method for preparing a catalyst for the removal of volatile organic compounds, the method comprising:

[0050] (1) A noble metal colloidal solution is prepared by first mixing the precursor of the noble metal, the reducing agent, the stabilizer and water.

[0051] (2) The mixture of the matrix metal oxide precursor and the noble metal colloidal solution are mixed for a second time to obtain the catalyst slurry;

[0052] (3) The catalyst slurry is coated on the surface of the support and subjected to a first drying and ozone calcination treatment to obtain the catalyst loaded with active components.

[0053] Among them, the precious metal is a combination of Pt and Ag or Pt;

[0054] The matrix metal oxide comprises single and / or composite oxides of Al and Ce, oxides of rare earth elements other than cerium, and zinc oxide.

[0055] In step (1), the precursor of the noble metal is preferably a soluble salt of the noble metal, such as at least one of acetate, nitrate, and chloride, preferably a nitrate. The noble metal is a combination of Pt and Ag or Pt, and the precursor of the noble metal is also a combination of the precursor of Pt and the precursor of Ag or the precursor of Pt, such as a combination of silver nitrate and platinum nitrate or platinum nitrate.

[0056] Preferably, the reducing agent is selected from at least one of ascorbic acid, borohydride (such as sodium borohydride or potassium borohydride), and citrate (such as sodium citrate or potassium citrate), more preferably ascorbic acid.

[0057] Preferably, the stabilizer is an organic amine; more preferably, the stabilizer is selected from at least one of diethylamine, triethylamine, and trimethylamine; and even more preferably, triethylamine.

[0058] In this invention, the order in which the precious metal precursor, reducing agent, stabilizer, and water are first mixed is not particularly limited, and those skilled in the art can add them in any order. Preferably, the precious metal precursor is mixed with water in the fifth step to obtain a precious metal salt solution; the reducing agent, stabilizer, and water are then mixed in the sixth step to obtain a mixed solution of the reducing agent and stabilizer. The two solutions can then be mixed, for example, the mixed solution of the reducing agent and stabilizer can be added to the precious metal salt solution to obtain a precious metal colloidal solution. In this invention, unless otherwise specified, mixing can be achieved by stirring, ultrasonication, or vibration.

[0059] Preferably, in the noble metal salt solution, the concentration of the Ag precursor is 0.2-10 mmol / L, based on the molar amount of the metal element.

[0060] Preferably, in the noble metal salt solution, the concentration of the Pt precursor is 0.2-5 mmol / L, based on the molar amount of the metal element.

[0061] Preferably, the weight ratio of Ag to Pt is 0.1-4:1, such as 0.1:1, 0.2:1, 0.4:1, 0.6:1, 0.8:1, 1:1, 2:1, 3:1, 4:1, and any range between any two values, more preferably 0.5-2.5:1.

[0062] Preferably, in the mixed solution of reducing agent and stabilizer, the concentration of reducing agent is 0.5-10 mmol / L, for example, it can be 0.5, 0.6, 0.8, 1, 2, 4, 6, 8, 10 mmol / L and any range between any two values.

[0063] Preferably, in the mixed solution of reducing agent and stabilizer, the concentration of stabilizer is 50-400 mmol / L, for example, it can be 50, 100, 150, 200, 250, 300, 350, 400 mmol / L or any range between any two values.

[0064] Preferably, the amount of reducing agent used is 0.5-5 mol compared to 1 mol of precious metal, for example, it can be 0.5, 0.6, 0.8, 1, 2, 4, 5 mmol / L and any range between any two values, preferably 1-3 mol, and the amount of stabilizer used is 10-50 mol, for example, it can be 10, 20, 30, 40, 50 mmol / L and any range between any two values, more preferably 15-30 mol.

[0065] The volumes of the mixed solution of reducing agent and stabilizer and the noble metal salt solution can be selected within a wide range, such as 0.1-10:1, or any range of 0.1:1, 0.2:1, 0.4:1, 0.6:1, 0.8:1, 1:1, 2:1, 4:1, 6:1, 8:1, 10:1, and any two of these values, preferably 0.5-2:1.

[0066] In step (2), the mixture of the matrix metal oxide precursor and the noble metal colloidal solution are mixed for the second time to obtain the catalyst slurry.

[0067] The matrix metal oxide comprises single and / or composite oxides of Al and Ce, rare earth element oxides other than cerium, and zinc oxide. When the single and / or composite oxides of Al and Ce are single oxides of Al and Ce, the alumina precursor, cerium oxide precursor, precursors of rare earth element oxides other than cerium, zinc oxide precursor, and water can be mixed in a third way to obtain a mixture of matrix metal oxide precursors.

[0068] Preferably, in step (2), when the single and / or composite oxides of Al and Ce contain Al-Ce composite oxides, the method for preparing the mixture of matrix metal oxide precursors includes: preparing Al-Ce composite oxides, and then mixing Al-Ce composite oxides, precursors of rare earth element oxides other than cerium, zinc oxide precursors and water in a fourth mixing process to obtain the mixture of matrix metal oxide precursors.

[0069] The preparation method of Al-Ce composite oxide can be a conventional method in the art, such as using a complexing agent to prepare Al-Ce composite oxide. Preferably, in step (2), the preparation method of Al-Ce composite oxide includes: mixing Al salt, Ce salt, complexing agent and water in a fourth mixing process to prepare a complexing agent solution, and then concentrating, drying and calcining the complexing agent solution to obtain Al-Ce composite oxide.

[0070] In step (2), the Al salt and Ce salt can be independently selected from at least one of their chloride, sulfate and nitrate salts; for example, the Al salt can be at least one of aluminum chloride, aluminum sulfate and aluminum nitrate, and the Ce salt can be at least one of cerium chloride, cerium sulfate and cerium nitrate.

[0071] Preferably, the complexing agent is selected from at least one of ethylene glycol, citric acid, and ethylenediaminetetraacetic acid (EDTA).

[0072] There are no particular restrictions on the order in which the Al salt, Ce salt, complexing agent, and water are mixed. For example, the Al salt, Ce salt, and water can be mixed first to obtain a mixed salt solution, and then the complexing agent can be added to it. The amount of water used is not particularly limited, as long as it is sufficient to keep the material in a solution state. For example, in molar terms, the content of Al and Ce elements in the mixed salt solution is 200-5000 mmol / L and 100-1000 mmol / L, respectively.

[0073] Preferably, the ratio of the molar amount of the complexing agent to the total molar amount of Al and Ce elements is 0.7-4:1, for example, it can be 0.7:1, 0.8:1, 1:1, 2:1, 3:1, 4:1 g / L, or any range between any two values.

[0074] Preferably, in step (2), the concentration conditions include a temperature of 60-90°C. For example, heating can be performed in a water bath to achieve the purpose of concentration. It should be understood that stirring can be carried out during the concentration process. There is no particular limitation on the concentration time, as long as it is sufficient to form a gel, for example, the time can be 4-7 hours.

[0075] Preferably, the conditions for the second drying include: a temperature of 80-140°C and a time of 6-10 hours.

[0076] Preferably, the calcination conditions include: a calcination temperature of 350-550℃ (e.g., 350, 400, 450, 500, 550℃, or any range between any two values), and a time of 1-5 hours. For example, the temperature can be increased to 350-550℃ at a rate of 3-15℃ / min and maintained for 1-5 hours. The calcination can be carried out in an oxygen-containing atmosphere (e.g., air).

[0077] Preferably, the rare earth elements other than cerium are selected from at least one of La, Pr and Y.

[0078] The precursors of rare earth element oxides other than cerium and zinc oxide precursors can each be independently selected from at least one of their chloride, sulfate, and nitrate salts, preferably nitrate salts. For example, among the precursors of rare earth element oxides other than cerium, the precursor of lanthanum oxide can be at least one of lanthanum chloride, lanthanum sulfate, and lanthanum nitrate; the precursor of praseodymium oxide can be at least one of praseodymium chloride, praseodymium sulfate, and praseodymium nitrate; the precursor of yttrium oxide can be at least one of yttrium chloride, yttrium sulfate, and yttrium nitrate; and the precursor of zinc oxide can be at least one of zinc chloride, zinc sulfate, and zinc nitrate.

[0079] In this invention, the mixing of Al-Ce composite oxide, rare earth oxide precursor, ZnO precursor and water can be achieved by grinding.

[0080] The third mixing method is preferably ball milling; preferably, the ball milling time is 1-5 hours and the rotation speed is 500-1500 rpm. A vibratory ball mill (such as the GZM-6 vibratory ball mill from Tianjin Shengyuan Equipment Co., Ltd.) can be used for ball milling.

[0081] Preferably, the ball milling conditions are such that the average particle diameter in the mixture of matrix metal oxide precursors is less than 15 μm. That is, the average particle diameter in the catalyst slurry is less than 15 μm.

[0082] Preferably, the solid content of the catalyst slurry is 5-35% by weight, for example, it can be 5, 10, 15, 20, 25, 30, 35% by weight or any range between any two values.

[0083] In step (3), the catalyst slurry is coated on the surface of the support and subjected to a first drying and ozone calcination treatment to obtain the catalyst loaded with the active components.

[0084] In this invention, the catalyst slurry can be uniformly loaded onto the surface of a carrier by spraying, coating, or immersion. After loading, it undergoes a first drying and calcination treatment to obtain a carrier with catalyst layers loaded on both the inner and outer surfaces. For example, the carrier can be immersed in the catalyst slurry for 5-30 seconds for loading. It should be understood that the catalyst slurry can be loaded onto the carrier through one or more processes.

[0085] Preferably, in step (3), the conditions for the first drying include: a temperature of 100-140°C and a time of 1-6 hours.

[0086] Preferably, in step (3), the conditions for ozone roasting include: roasting in an ozone atmosphere at a temperature of 350-550℃ (for example, it can be 350, 400, 450, 500, 550℃ or any range between any two values), for a time of 1-3 hours. For example, the temperature can be increased to 350-550℃ at a rate of 3-15℃ / min and maintained for 1-3 hours. The ozone atmosphere is achieved by an ozone generator (such as the OZ-004 ozone generator from Qingdao Zhongke Sanyang Co., Ltd.).

[0087] Preferably, the catalyst slurry loading is such that, based on the volume of the carrier, the loading of the active component is 10-200 g / L, for example, it can be 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200 g / L and any range between any two values, preferably 40-160 g / L.

[0088] Preferably, the amounts of each component are such that, based on the volume of the carrier, the loading of noble metals is 0.1-10 g / L, preferably 0.3-7 g / L; the loading of single and / or composite oxides of Al and Ce is 30-120 g / L, preferably 60-95 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L, preferably 7-12 g / L; and the loading of zinc oxide is 2-12 g / L, preferably 4-10 g / L.

[0089] Preferably, when the precious metal is a combination of Pt and Ag, the amount of each component is such that, based on the volume of the carrier, the loading of Ag is 0.2-4 g / L, preferably 0.4-2 g / L; and the loading of Pt is 0.1-3 g / L, preferably 0.2-1 g / L.

[0090] Preferably, the molar ratio of aluminum to cerium is 1-10:1, more preferably 4-8:1.

[0091] It should be understood that, in this invention, the preferred conditions are more conducive to improving catalyst performance, reducing catalytic temperature, and improving catalytic effect.

[0092] A third aspect of the present invention provides a catalyst prepared according to the method described above.

[0093] The fourth aspect of the present invention relates to the application of the VOCs oxidation catalyst described above in the catalytic oxidation of VOCs.

[0094] The present invention will be described in detail below through embodiments. The following embodiments will further illustrate the present invention, but are not intended to limit the present invention.

[0095] The average particle diameter in the catalyst slurry was the equivalent volume diameter obtained by laser particle size analysis. Experimental instrument: Malvern Mastersizer 3000.

[0096] The activity evaluation of the toluene catalytic oxidation reaction was performed on a micro fixed-bed reactor designed and manufactured by Tianjin Pengxiang Technology Co., Ltd., equipped with an MKS Multigas 2030 infrared detector. The reaction was carried out at atmospheric pressure, with an initial temperature of 150℃, and a programmed temperature increase at a rate of 3℃ / min until complete toluene conversion. The inlet gas composition was 450ppm C7H8 / 7% O2 / N2, and the space velocity was 12000 h⁻¹. -1 .

[0097] The carrier is a VOC-specific cordierite honeycomb carrier purchased from Pingxiang Guanlin Environmental Protection Technology Co., Ltd. The carrier has a pore density of 300 pores / square inch, a cross-sectional area of ​​1.5 square millimeters per pore, an open porosity of 70%, and a circular shape.

[0098] Example 1

[0099] (1) Preparation of noble metal colloidal solution: Prepare a mixed solution of 1 mmol / L platinum nitrate and 2 mmol / L silver nitrate, and a mixed solution of 5 mmol / L ascorbic acid and 60 mmol / L triethylamine. The volume ratio of the noble metal solution to the mixed solution is 1:1. Under stirring conditions, the mixed solution is quickly added to the prepared noble metal solution and stirred continuously for 10 minutes to obtain the noble metal colloidal solution.

[0100] (2) Prepare a mixed salt solution of aluminum nitrate and cerium nitrate with a molar ratio of aluminum to cerium of 8:1. Add citric acid with a molar ratio of citric acid to metal of 2:1 under stirring. Heat and stir in an 80°C water bath for 6 hours until the solvent evaporates. Dry the precursor at 100°C for 8 hours. Then calcine it in an air atmosphere, raise the temperature to 450°C at a rate of 5°C / min, and hold for 2 hours.

[0101] (3) Add appropriate amounts of Al-Ce composite oxide, lanthanum nitrate and zinc nitrate to deionized water, and use a vibratory ball mill (Tianjin Shengyuan Equipment Co., Ltd., GZM-6) to fully grind the above mixture. The specific grinding conditions are: ball milling time 2.5h, rotation speed 1000rpm, and the average particle diameter in the mixture after ball milling is 10.3μm. After stirring the ball-milled mixture for 1 hour, add the above precious metal colloidal solution and continue stirring for 1 hour to obtain the catalyst slurry. Control the solid content of the slurry to be 20% by weight. Then, uniformly coat the catalyst slurry on the surface of a 300-mesh regular structure carrier so that the total coating amount of active components on each liter of ceramic carrier is 80g. In terms of elements, the content of platinum is 0.2g and the content of silver is 0.2g; in terms of oxides, the content of Al-Ce composite oxide is 68g; in terms of oxides, the content of lanthanum oxide is 7g; and in terms of oxides, the content of zinc oxide is 4.6g.

[0102] (4) The support coated with catalyst slurry was dried at 120°C for 2 hours, and then subjected to ozone calcination treatment. The temperature was increased to 380°C at a rate of 5°C / min and held for 2 hours to obtain VOCs catalytic oxidation catalyst.

[0103] The inventors discovered that step (1) prepares noble metal alloy particles with a diameter in the range of 10-30 nm. Figure 1 After high-temperature ozone calcination, the alloy particles are redispersed, and the particle size is reduced to 2-4 nm. Figure 2 ), and the activity was significantly improved.

[0104] Example 2

[0105] (1) Preparation of noble metal colloidal solution: Prepare a mixed solution of 2 mmol / L platinum nitrate and 5 mmol / L silver nitrate, and a mixed solution of 8 mmol / L ascorbic acid and 200 mmol / L triethylamine. The volume ratio of the noble metal solution to the mixed solution is 1:1. Under stirring conditions, the mixed solution is quickly added to the prepared noble metal solution and stirred continuously for 15 minutes to obtain the noble metal colloidal solution.

[0106] (2) Prepare a mixed salt solution of aluminum nitrate and cerium nitrate with a molar ratio of aluminum to cerium of 7:1. Add citric acid with a molar ratio of citric acid to metal of 2:1 under stirring. Heat and stir in an 80°C water bath for 6 hours until the solvent evaporates. Dry the precursor at 100°C for 8 hours. Then calcine it in an air atmosphere, raise the temperature to 400°C at a rate of 7°C / min, and hold for 2 hours.

[0107] (3) Add appropriate amounts of Al-Ce composite oxide, lanthanum nitrate and zinc nitrate to deionized water, and use a vibratory ball mill (Tianjin Shengyuan Equipment Co., Ltd., GZM-6) to fully grind the above mixture. The specific grinding conditions are: ball milling time 3h, rotation speed 1200rpm, and the average particle diameter in the mixture after ball milling is 7.2μm. After stirring the ball-milled mixture for 1.5 hours, add the above precious metal-cerium mixed solution and continue stirring for 1.5 hours to obtain the catalyst slurry. Control the solid content of the slurry to be 25% by weight. Then, uniformly coat the catalyst slurry on the surface of a 300-mesh regular structure carrier so that the total coating amount of active components on each liter of ceramic carrier is 100g. In terms of elements, the content of platinum is 0.4g and the content of silver is 0.5g; in terms of oxides, the content of Al-Ce composite oxide is 82g; in terms of oxides, the content of lanthanum oxide is 11.1g; and in terms of oxides, the content of zinc oxide is 6g.

[0108] (4) The support coated with catalyst slurry was dried at 120°C for 7 hours, and then subjected to ozone calcination treatment. The temperature was increased to 430°C at a rate of 6°C / min and held for 3 hours to obtain VOCs catalytic oxidation catalyst.

[0109] Example 3

[0110] (1) Preparation of noble metal colloidal solution: Prepare a mixed solution of 1 mmol / L platinum nitrate and 6 mmol / L silver nitrate, and a mixed solution of 8 mmol / L ascorbic acid and 200 mmol / L triethylamine. The volume ratio of the noble metal solution to the mixed solution is 1:1. Under stirring conditions, the mixed solution is quickly added to the prepared noble metal solution and stirred continuously for 15 minutes to obtain the noble metal colloidal solution.

[0111] (2) Prepare a mixed salt solution of aluminum nitrate and cerium nitrate with a molar ratio of aluminum to cerium of 6:1. Add citric acid with a molar ratio of citric acid to metal of 2:1 under stirring. Heat and stir in an 80°C water bath for 6 hours until the solvent evaporates. Dry the precursor at 100°C for 8 hours. Then calcine it in an air atmosphere, raise the temperature to 400°C at a rate of 7°C / min, and hold for 2 hours.

[0112] (3) Add appropriate amounts of Al-Ce composite oxide, lanthanum nitrate and zinc nitrate to deionized water, and use a vibratory ball mill (Tianjin Shengyuan Equipment Co., Ltd., GZM-6) to fully grind the above mixture. The specific grinding conditions are: ball milling time 3h, rotation speed 800rpm, and the average particle diameter in the mixture after ball milling is 12.2μm. After stirring the ball-milled mixture for 1.5 hours, add the above precious metal-cerium mixed solution and continue stirring for 1.5 hours to obtain the catalyst slurry. Control the solid content of the slurry to be 20% by weight. Then, uniformly coat the catalyst slurry on the surface of a 300-mesh regular structure carrier so that the total coating amount of active components on each liter of ceramic carrier is 100g. In terms of elements, the content of platinum is 0.2g and the content of silver is 0.7g; in terms of oxides, the content of Al-Ce composite oxide is 82g; in terms of oxides, the content of lanthanum oxide is 11.1g; and in terms of oxides, the content of zinc oxide is 6g.

[0113] (4) The support coated with catalyst slurry was dried at 130°C for 5 hours, and then subjected to ozone calcination treatment. The temperature was increased to 400°C at a rate of 7°C / min and held for 2 hours to obtain VOCs catalytic oxidation catalyst.

[0114] Example 4

[0115] Example 4 prepared a Pt colloidal solution, in which only platinum nitrate was added in step (1), the content of the noble metal Pt on each liter of carrier was 0.4 g, and the loading of other components and operating conditions were the same as in Example 1.

[0116] Example 5

[0117] In Example 5, equal amounts of Al2O3 and CeO2 were used to replace the Al-Ce composite oxide, wherein the aluminum-cerium ratio was the same as that in the Al-Ce composite oxide in Example 1, and other conditions were the same as in Example 1.

[0118] Example 6

[0119] In Example 6, praseodymium oxide and yttrium oxide were used instead of lanthanum oxide, with 2g of praseodymium oxide and 5g of yttrium oxide per liter of ceramic carrier, and other conditions were the same as in Example 1.

[0120] Comparative Example 1

[0121] Comparative Example 1 does not prepare Ag-Pt alloy, that is, it does not perform step (1). In step (3), silver nitrate and platinum nitrate solutions are added. The content of noble metals Ag and Pt and other conditions are the same as in Example 1.

[0122] Comparative Example 2

[0123] Comparative Example 2 was not roasted in an ozone atmosphere, but in an air atmosphere, with the temperature increased to 500°C at a rate of 6°C / min and held for 2 hours, with other conditions the same as in Example 1.

[0124] Comparative Example 3

[0125] Comparative Example 3 used a custom-made commercial cordierite VOCs catalyst (precious metal content 0.4 g / L) with a single cubic columnar straight channel inside; it was cut into cylinders of the same size as the example (3 cm in diameter at the bottom and 1 cm in height) for activity evaluation.

[0126] Comparative Example 4

[0127] Comparative Example 4 prepared an Ag colloidal solution, in which only silver nitrate was added in step (1), the content of the noble metal Ag on each liter of carrier was 0.4g, and other conditions were the same as in Example 1.

[0128] Comparative Example 5

[0129] Comparative Example 5 did not add zinc oxide during the slurry preparation process, and other conditions were the same as in Example 1, with the total loading remaining unchanged.

[0130] The catalytic performance of the catalysts prepared in the examples and comparative examples was tested.

[0131] Table 1. T values ​​for each catalyst sample 50 T 99

[0132]

[0133]

[0134] As can be seen from Table 1, the T values ​​of the VOCs catalytic materials obtained in the examples are... 50 and T 99 The conversion temperatures of toluene are all lower than those of the comparative example, meaning that the catalyst performance is better than that of the comparative example. The VOCs catalytic material prepared by this invention has a higher efficiency in degrading pollutants and is expected to be promoted to the preparation of various fixed-bed catalytic materials, showing broad application prospects.

[0135] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A catalyst for the removal of volatile organic compounds, characterized in that, The catalyst comprises a support and an active component supported on the support; The active component comprises a noble metal and a matrix metal oxide, wherein the noble metal is an Ag-Pt alloy; the matrix metal oxide comprises single and / or composite oxides of Al and Ce, oxides of rare earth elements other than cerium, and zinc oxide. The particle size of Ag-Pt alloys is 1-8 nm; Based on the volume of the carrier, the loading capacity of Ag is 0.2-4 g / L; the loading capacity of Pt is 0.1-3 g / L. Based on the volume of the carrier, the loading of single and / or composite oxides of Al and Ce is 30-120 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L; and the loading of zinc oxide is 2-12 g / L. The method for preparing the catalyst includes: (1) A noble metal colloidal solution is prepared by first mixing the precursor of the noble metal, the reducing agent, the stabilizer and water; (2) The mixture of matrix metal oxide precursor and noble metal colloidal solution is mixed for a second time to obtain catalyst slurry; (3) The catalyst slurry is coated on the surface of the support and subjected to a first drying and ozone calcination treatment to obtain the catalyst loaded with active components; The conditions for ozone roasting include: roasting in an ozone atmosphere at a temperature of 350-550℃ for 1-3 hours.

2. The catalyst according to claim 1, wherein, Based on the volume of the carrier, the total loading of the active components is 10-200 g / L.

3. The catalyst according to claim 2, wherein, Based on the volume of the carrier, the total loading of the active components is 40-160 g / L.

4. The catalyst according to any one of claims 1-3, wherein, Based on the volume of the carrier, the loading of precious metals is 0.1-10 g / L; and / or Based on the volume of the carrier, the loading of Ag is 0.4-2 g / L; the loading of Pt is 0.2-1 g / L; and / or In the precious metal, the weight ratio of Ag to Pt is 0.1-4:

1.

5. The catalyst according to claim 4, wherein, Based on the volume of the carrier, the loading of precious metals is 0.3-7 g / L; and / or In the precious metal, the weight ratio of Ag to Pt is 0.5-2.5:

1.

6. The catalyst according to any one of claims 1-3 and 5, wherein, Based on the volume of the support, the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or The molar ratio of aluminum to cerium is 1-10:1; and / or The single and / or composite oxides of Al and Ce comprise Al-Ce composite oxides; and / or Rare earth elements other than cerium are selected from at least one of La, Pr, and Y.

7. The catalyst according to claim 6, wherein, The molar ratio of aluminum to cerium is 4-8:

1.

8. The catalyst according to claim 4, wherein, Based on the volume of the support, the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or The molar ratio of aluminum to cerium is 1-10:1; and / or The single and / or composite oxides of Al and Ce comprise Al-Ce composite oxides; and / or Rare earth elements other than cerium are selected from at least one of La, Pr, and Y.

9. The catalyst according to claim 8, wherein, The molar ratio of aluminum to cerium is 4-8:

1.

10. The catalyst according to any one of claims 1-3, 5, 7-9, wherein, The carrier is a regular structure carrier.

11. The catalyst according to claim 10, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

12. The catalyst according to claim 4, wherein, The carrier is a regular structure carrier.

13. The catalyst according to claim 12, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

14. The catalyst according to claim 6, wherein, The carrier is a regular structure carrier.

15. The catalyst according to claim 14, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

16. A method for preparing a catalyst for the removal of volatile organic compounds according to any one of claims 1-15, characterized in that, The method includes: (1) A noble metal colloidal solution is prepared by first mixing the precursor of the noble metal, the reducing agent, the stabilizer and water; (2) The mixture of matrix metal oxide precursor and noble metal colloidal solution is mixed for a second time to obtain catalyst slurry; (3) The catalyst slurry is coated on the surface of the support and subjected to a first drying and ozone calcination treatment to obtain the catalyst loaded with active components; Among them, the precious metal is a combination of Pt and Ag; The matrix metal oxide comprises single and / or composite oxides of Al and Ce, rare earth element oxides other than cerium, and zinc oxide. The conditions for ozone roasting include: roasting in an ozone atmosphere at a temperature of 350-550℃ for 1-3 hours.

17. The method according to claim 16, wherein, In step (2), when the single and / or composite oxides of Al and Ce contain Al-Ce composite oxides, the preparation method of the matrix metal oxide precursor mixture includes: preparing Al-Ce composite oxides, and then mixing Al-Ce composite oxides, precursors of rare earth element oxides other than cerium, zinc oxide precursors and water in a third mixing process to obtain the matrix metal oxide precursor mixture.

18. The method according to claim 17, wherein, In step (2), the preparation method of the Al-Ce composite oxide includes: mixing Al salt, Ce salt, complexing agent and water in a fourth mixing process to prepare a complexing agent solution, and then concentrating, drying and calcining the complexing agent solution to obtain the Al-Ce composite oxide.

19. The method according to any one of claims 16-18, wherein, In step (1), the precursor of the noble metal is a soluble salt of the noble metal; and / or The reducing agent is selected from at least one of ascorbic acid, borohydride, and citrate; and / or The stabilizer is an organic amine.

20. The method according to claim 19, wherein, In step (1), the precursor of the noble metal is at least one of acetate, nitrate, and chloride; and / or The reducing agent is ascorbic acid; and / or The stabilizer is selected from at least one of diethylamine, triethylamine, and trimethylamine; and / or Compared to 1 mol of precious metal, the amount of reducing agent used is 0.5-5 mol, and the amount of stabilizer used is 10-50 mol.

21. The method according to claim 20, wherein, In step (1), the precursor of the noble metal is a nitrate; and / or The stabilizer is triethylamine; and / or Compared to 1 mol of precious metal, the amount of reducing agent used is 1-3 mol, and the amount of stabilizer used is 15-30 mol.

22. The method according to any one of claims 16-18, wherein, Rare earth elements other than cerium are selected from at least one of La, Pr, and Y; and / or The precursors of rare earth element oxides other than cerium and the zinc oxide precursor are each independently selected from at least one of their chloride, sulfate, and nitrate salts; and / or The solid content of the catalyst slurry is 5-35% by weight.

23. The method according to claim 18, wherein, In step (2), the Al salt and Ce salt are each independently selected from at least one of their chloride, sulfate, and nitrate salts; and / or The molar ratio of the complexing agent to the total molar ratio of Al and Ce is 0.7-4:1; and / or The complexing agent is selected from at least one of ethylene glycol, citric acid, and ethylenediaminetetraacetic acid.

24. The method of claim 17, wherein, The third mixing method is ball milling.

25. The method according to claim 24, wherein, The ball milling conditions ensure that the average particle diameter in the mixture of matrix metal oxide precursors is less than 15 μm.

26. The method according to claim 18, wherein, In step (2), the concentration conditions include: a temperature of 60-90°C, and a water bath heating method; and / or The conditions for the second drying process include: a temperature of 80-140 ℃ and a time of 6-10 hours; and / or The roasting conditions include: a roasting temperature of 350-550℃ and a roasting time of 1-5 hours.

27. The method according to any one of claims 16-18, wherein, In step (3), the conditions for the first drying include: a temperature of 100-140 ℃ and a time of 1-6 h; and / or The catalyst slurry loading is such that, based on the volume of the support, the loading of the active component is 10-200 g / L.

28. The method according to claim 27, wherein, The catalyst slurry loading is such that, based on the volume of the support, the loading of the active component is 40-160 g / L.

29. The method according to any one of claims 16-18, 20-21, 23-26, and 28, wherein, The amounts of each component are adjusted so that, based on the volume of the carrier, the loading of noble metals is 0.1-10 g / L; the loading of single and / or composite oxides of Al and Ce is 30-120 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L; and the loading of zinc oxide is 2-12 g / L.

30. The method according to claim 29, wherein, The amounts of each component are adjusted such that, based on the volume of the carrier, the loading of noble metals is 0.3-7 g / L; the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.2-4 g / L; the loading of Pt is 0.1-3 g / L; and / or The weight ratio of Ag to Pt is 0.1-4:1; and / or The molar ratio of aluminum to cerium is 1-10:

1.

31. The method according to claim 30, wherein, When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.4-2 g / L; the loading of Pt is 0.2-1 g / L; and / or The weight ratio of Ag to Pt is 0.5-2.5:1; and / or The molar ratio of aluminum to cerium is 4-8:

1.

32. The method according to claim 19, wherein, The amounts of each component are adjusted so that, based on the volume of the carrier, the loading of noble metals is 0.1-10 g / L; the loading of single and / or composite oxides of Al and Ce is 30-120 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L; and the loading of zinc oxide is 2-12 g / L.

33. The method according to claim 32, wherein, The amounts of each component are adjusted such that, based on the volume of the carrier, the loading of noble metals is 0.3-7 g / L; the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.2-4 g / L; the loading of Pt is 0.1-3 g / L; and / or The weight ratio of Ag to Pt is 0.1-4:1; and / or The molar ratio of aluminum to cerium is 1-10:

1.

34. The method according to claim 33, wherein, When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.4-2 g / L; the loading of Pt is 0.2-1 g / L; and / or The weight ratio of Ag to Pt is 0.5-2.5:1; and / or The molar ratio of aluminum to cerium is 4-8:

1.

35. The method according to claim 22, wherein, The amounts of each component are adjusted so that, based on the volume of the carrier, the loading of noble metals is 0.1-10 g / L; the loading of single and / or composite oxides of Al and Ce is 30-120 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L; and the loading of zinc oxide is 2-12 g / L.

36. The method according to claim 35, wherein, The amounts of each component are adjusted such that, based on the volume of the carrier, the loading of noble metals is 0.3-7 g / L; the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.2-4 g / L; the loading of Pt is 0.1-3 g / L; and / or The weight ratio of Ag to Pt is 0.1-4:1; and / or The molar ratio of aluminum to cerium is 1-10:

1.

37. The method of claim 36, wherein, When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.4-2 g / L; the loading of Pt is 0.2-1 g / L; and / or The weight ratio of Ag to Pt is 0.5-2.5:1; and / or The molar ratio of aluminum to cerium is 4-8:

1.

38. The method according to claim 27, wherein, The amounts of each component are adjusted so that, based on the volume of the carrier, the loading of noble metals is 0.1-10 g / L; the loading of single and / or composite oxides of Al and Ce is 30-120 g / L; the loading of rare earth element oxides other than cerium is 6-15 g / L; and the loading of zinc oxide is 2-12 g / L.

39. The method according to claim 38, wherein, The amounts of each component are adjusted such that, based on the volume of the carrier, the loading of noble metals is 0.3-7 g / L; the loading of single and / or composite oxides of Al and Ce is 60-95 g / L; the loading of rare earth element oxides other than cerium is 7-12 g / L; the loading of zinc oxide is 4-10 g / L; and / or When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.2-4 g / L; the loading of Pt is 0.1-3 g / L; and / or The weight ratio of Ag to Pt is 0.1-4:1; and / or The molar ratio of aluminum to cerium is 1-10:

1.

40. The method according to claim 39, wherein, When the precious metals are a combination of Pt and Ag, the amounts of each component are such that, based on the volume of the support, the loading of Ag is 0.4-2 g / L; the loading of Pt is 0.2-1 g / L; and / or The weight ratio of Ag to Pt is 0.5-2.5:1; and / or The molar ratio of aluminum to cerium is 4-8:

1.

41. The method according to any one of claims 16-18, 20-21, 23-26, 28, and 30-40, wherein, The carrier is a regular structure carrier.

42. The method according to claim 41, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

43. The method according to claim 19, wherein, The carrier is a regular structure carrier.

44. The method according to claim 43, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

45. The method according to claim 22, wherein, The carrier is a regular structure carrier.

46. ​​The method according to claim 45, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

47. The method of claim 27, wherein, The carrier is a regular structure carrier.

48. The method according to claim 47, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

49. The method according to claim 29, wherein, The carrier is a regular structure carrier.

50. The method according to claim 49, wherein, The carrier has a cross-sectional pore density of 50-400 pores / square inch and an open porosity of 20-80%; and / or The carrier is selected from at least one of cordierite, mullite, diamond, corundum, zirconium corundum, quartz, nepheline, feldspar, alumina, and metal alloys.

51. The catalyst prepared by the method according to any one of claims 16-50.

52. The use of the catalyst according to any one of claims 1-15 and 51 in the catalytic oxidation of VOCs.

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