Metal powder felt filter material with catalytic function and its preparation method

Abstract

The application discloses a metal powder felt filter material with catalytic function and a preparation method thereof, and belongs to the technical field of high-temperature flue gas dust and denitration integration. The metal powder felt comprises a felt base and a molecular sieve catalyst layer; the molecular sieve catalyst layer is formed on the surface of the felt base, and part of the catalyst layer penetrates into the inside of the metal powder felt base; the molecular sieve catalyst layer is composed of a catalyst, a binder, a structure aid, a pore-forming agent and polydimethylsiloxane. Micropores formed by the pore-forming agent in the coating make the metal powder felt maintain original high air permeability; the molecular sieve catalyst is uniformly dispersed on the surface of the coating and in the micropores, and there are more catalytic active sites; and the molecular sieve catalyst layer has high mechanical strength and strong water resistance, and can be used for a long time in a high-temperature and high-humidity environment, so that the prepared metal powder felt filter material can realize high-temperature flue gas dust and denitration integration removal.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated dust removal and denitrification of high-temperature flue gas, and particularly relates to a metal powder felt filter material with a catalytic function and a preparation method thereof. Background Art

[0002] NO in air pollutants x It mainly comes from industrial fixed sources and mobile sources such as vehicles. x In terms of end-of-pipe emission reduction technologies, ammonia selective catalytic reduction (NH3-SCR) has the advantages of high denitrification efficiency (up to 90% or more), minimal environmental impact of reaction exhaust, and high reducing agent utilization. Zeolite molecular sieves are a commonly used denitrification catalyst due to their high pore connectivity, large specific surface area, and excellent gas adsorption, mass transfer, and heat transfer capabilities. However, in practical applications, powdered catalysts still face the problems of dust and SO2 poisoning, which limits the application of zeolite molecular sieves and requires the construction of structured molecular sieve catalysts on suitable carriers.

[0003] High-temperature dust removal technology utilizes high-temperature filter media to remove and purify gases directly under high-temperature conditions (≥300°C). Metal powder felt is a highly efficient filter material characterized by strong corrosion resistance, high-temperature resistance, high strength, and high filtration accuracy. Compared to metal fiber felt, it offers advantages such as lower cost and a simpler preparation process. Integrating high-temperature filtration technology with SCR denitrification would not only reduce the device footprint, but also protect the catalyst from wear by intercepting dust through the filter media, thereby extending catalyst life.

[0004] CN108704390A discloses a method for preparing a high-temperature denitrification and dust removal metal fiber filter material, wherein the filter material prepared by the method is pre-loaded with a layer of Al2O3 solidified layer on the surface of the metal filter material fiber by an electrochemical deposition method to improve the loading firmness of the subsequent coating catalyst. CN106215546B discloses a method for preparing a self-assembled catalyst coating filter material, wherein the method provides a preparation method when the base material of the coating filter material is metal, specifically, a layer of adsorption solidified layer composed of a polyelectrolyte and a curing agent is pre-impregnated and coated on the base, and then the catalyst particles are sprayed on the base. These schemes all use metal fiber felt as a carrier, and the catalyst loading method is complicated and difficult to achieve large-scale preparation. The present invention uses metal powder felt as a carrier, which is a simple and convenient preparation scheme, and solves the problem of coupling high-temperature filtration technology with molecular sieve catalyst SCR denitrification technology.

[0005] Because the pore size of the metal powder felt is similar to that of the finished molecular sieve particles, the molecular sieve particles are not easily implanted into the interior of the metal powder felt. A porous molecular sieve catalyst layer is constructed on the surface of the felt base, and part of the coating penetrates into the felt base. While not affecting the air permeability of the metal powder felt itself, combined with the good mechanical strength of the coating itself, an ideal loading effect is achieved. This method is simple and easy to operate, and has good prospects for large-scale application. Summary of the Invention

[0006] In order to solve the problem of coupling the metal powder felt high-temperature filtration technology and the molecular sieve catalyst SCR denitrification technology in the above-mentioned technology, the purpose of the present invention is to provide a metal powder felt filter material with catalytic function and a preparation method thereof. The molecular sieve denitrification catalyst loaded on the metal powder felt has high bonding strength, good dispersion performance and high catalyst coverage.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A metal powder felt filter material with catalytic function includes a felt base and a molecular sieve catalyst layer; the molecular sieve catalyst layer is formed on the surface of the felt base, and the catalyst layer partially penetrates into the interior of the metal powder felt base; the molecular sieve catalyst layer is composed of a catalyst, a binder, a structural additive, a pore-forming agent and polydimethylsiloxane.

[0009] Preferably, the molecular sieve catalyst in the molecular sieve catalyst layer is one of Fe-ZSM-5, Cu-ZSM-5, and Cu-SSZ-13. Preferably, the binder is a substance that has a bonding effect and can protect the activity of the catalyst. Specifically, the binder is one or both of nano-alumina and kaolin. Preferably, the structural additive in the molecular sieve catalyst layer is low-melting-point glass powder. Preferably, the pore-forming agent is one or both of polymethyl methacrylate, polyvinyl pyrrolidone, and citric acid. Preferably, the solvent used to dissolve polydimethylsiloxane is one of n-hexane, n-pentane, and toluene.

[0010] Preferably, the thickness of the metal powder felt substrate is between 200 and 400 μm, and the thickness of the molecular sieve catalyst layer is between 50 and 100 μm.

[0011] Preferably, the metal powder felt can be one of stainless steel powder felt, nickel alloy powder felt, and Fe / Al powder felt, and has a three-dimensional porous structure, wherein the porosity of the metal powder felt is 20-60%, and the pore size range is 5-15 μm.

[0012] A method for preparing a metal powder felt filter material with catalytic function as described above, wherein the molecular sieve denitrification catalyst in the metal powder felt filter material covers all the powder and is evenly dispersed, the coating has high loading strength, and has the functions of filtering dust removal and removing NOx function.

[0013] The following steps are involved:

[0014] Step 1: mixing and ball-milling a catalyst, a binder, and a structural additive, wherein the mass ratio of the binder, the structural additive, and the catalyst is 0.1-1:0.1-0.3:1; adding water and a pore-forming agent to prepare a mixed slurry a, and adjusting the pH to 2-4, wherein the mass ratio of water, the pore-forming agent, and the catalyst is 1-1.5:3-5:1;

[0015] Step 2: applying the mixed slurry a to the surface of the metal powder felt substrate;

[0016] Step 3: Dissolve polydimethylsiloxane and a curing agent in a solvent, fully stir or ultrasonically disperse, and prepare a solution b with a polydimethylsiloxane mass fraction of 5 to 10 wt%, wherein the mass ratio of the curing agent to the polydimethylsiloxane is 0.1:1;

[0017] Step 4: Dry the metal powder felt obtained in step 2, heat it to 400-700°C for curing, immerse it in solution b and let it stand; take it out, cure it at 350-500°C, pyrolyze it, take it out and let it cool naturally to obtain the metal powder felt filter material with catalytic function.

[0018] Preferably, the structural additive is low-melting-point glass powder; preferably, the pore-forming agent is one or more of polymethyl methacrylate, polyvinyl pyrrolidone, and citric acid; preferably, the solvent used to dissolve polydimethylsiloxane is one of n-hexane, n-pentane, and toluene; preferably, the chemical required to adjust the pH is a 10wt% nitric acid solution.

[0019] In step 1, the catalyst, binder and structural additive are pre-dispersed to improve the dispersion effect of the catalyst. The aluminum component in the binder can protect the activity of the molecular sieve catalyst in a strong acid environment and enhance the adhesion between particles. A new dense coating will be formed during the baking of the low-melting point glass powder to improve the mechanical strength of the coating. The purpose of coating with polydimethylsiloxane in step 4 is to adapt the coating to the high temperature and high humidity environment and to have a secondary bonding effect on the catalyst.

[0020] In step 1, the setting parameters of the ball mill are 350-550 rpm, preferably, the rotation speed of the ball mill is 450-500 rpm, and the ball milling time is 10-30 min, preferably, the ball milling time is 15-25 min.

[0021] In step 3, the curing agent is one of methyltrimethoxysilane and ethyl orthosilicate, preferably, the curing agent is methyltrimethoxysilane;

[0022] Preferably, the stirring or ultrasonic treatment in step 4 is performed for at least 10 minutes; the drying temperature in step 4 is 60-100°C, the drying time is 50-100 minutes, and the curing time in step 4 is at least 10 minutes. The purpose of drying is to evaporate water; the purpose of curing is to allow the binder and structural additives in the coating to function as a bond. The curing time is not limited, provided that the coating meets the mechanical strength requirements, but is preferably at least 10 minutes.

[0023] In step 6, the polydimethylsiloxane layer is a film layer of organic silicon and inorganic silicon hybrid cross-linked after removing some unstable organic groups at high temperature. The purpose is to strengthen the weak parts of the coating, repair the cracks of the coating, and further prevent the catalyst from pulverizing and falling off.

[0024] The beneficial effects of the present invention are:

[0025] (1) The present invention constructs a catalytic coating with a porous structure on the surface of the metal powder felt. On the one hand, the air permeability and mechanical strength of the coating are improved by adding different additives, solving the problem that the metal powder felt loaded with catalyst is easily clogged and cannot be filtered. On the other hand, the secondary coating of the polydimethylsiloxane layer reduces the gaps between the catalyst particles, and the polydimethylsiloxane layer almost completely covers the powder felt, indirectly enhancing the life of the filter material.

[0026] (2) The metal powder felt filter material with catalytic function of the present invention has the dual functions of high-temperature dust removal and denitrification, which can achieve the dual functions of flue gas dust and NO x Efficient integrated removal at high temperatures.

[0027] (3) There is almost no organic substance poisoning in the raw materials and preparation process, and the preparation method is easy to implement and is particularly suitable for industrial production; while maintaining a certain filtering performance of the metal powder felt, the maximum loading capacity of the metal powder felt as a carrier is increased, and the catalyst particles are firmly bonded and not easy to fall off. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a surface scanning electron microscope image of the blank metal powder felt substrate used in Example 1 of the present invention.

[0029] Figure 2 This is a surface scanning electron microscope image of the metal powder felt filter material with catalytic function described in Example 1 of the present invention.

[0030] Figure 3 This is a surface scanning electron microscope image of the metal powder felt catalytic filter material (control group) prepared by the traditional impregnation method corresponding to Example 1 of the present invention.

[0031] Figure 4 This is a cross-sectional scanning electron microscope image of the blank metal powder felt substrate used in Example 1 of the present invention.

[0032] Figure 5 This is a cross-sectional scanning electron microscope image of the metal powder felt filter material with catalytic function described in Example 1 of the present invention.

[0033] Figure 6 This is a comparison chart of the catalytic denitrification efficiency of the catalytic filter materials prepared in Examples 2-3 of the present invention and the corresponding control group.

[0034] Figure 7 2-3 and the corresponding control group of the catalytic filter materials prepared in accordance with the present invention.

[0035] Figure 8 This is a comparison chart of the shedding rates of the catalytic filter materials prepared in Examples 2-3 of the present invention and the corresponding control group. DETAILED DESCRIPTION

[0036] In order to make the contents of the present invention easier to understand, the technical solutions of the present invention are further described below in conjunction with specific implementation methods, but the present invention is not limited thereto.

[0037] Unless otherwise specified, the terms used herein have the meanings commonly understood by those skilled in the art. To facilitate understanding of the present invention, some of the terms used herein are defined below.

[0038] All numerical designations used in the specification and claims, such as pH, temperature, time, and concentration, including ranges, are approximate. It is understood, although not always explicitly stated, that all numerical designations are preceded by the term "about." It is also understood, although not always explicitly stated, that the reagents described herein are merely examples and that equivalents thereof are known in the art.

[0039] The present invention will be described in detail below with reference to the embodiments and accompanying drawings.

[0040] Example 1:

[0041] A method for preparing a metal powder felt filter material with catalytic function comprises the following steps:

[0042] Step 1: ball-milling a mixture of Fe-ZSM-5 molecular sieve catalyst, kaolin, and low-melting-point glass powder, wherein the mass ratio of Fe-ZSM-5 molecular sieve catalyst, kaolin, and low-melting-point glass powder is 2:1:0.3, the ball-milling parameters are 500 rpm, and the ball-milling time is 20 min; water and citric acid are added to prepare a mixed slurry a, wherein the mass ratio of water, citric acid, and catalyst is 1.5:5:1;

[0043] Step 2: Apply the mixed slurry a to the surface of a 316L stainless steel powder felt substrate using a 100 μm wire rod coater;

[0044] Step 3: Dissolve polydimethylsiloxane and methyltrimethoxysilane in n-hexane, and ultrasonically disperse for 15 minutes to prepare a solution b containing 5 wt% polydimethylsiloxane, wherein the methyltrimethoxysilane accounts for 0.1% of the mass of the polydimethylsiloxane;

[0045] Step 4: Dry the 316L stainless steel powder felt coating in step 2 at 80°C, then heat it to 500°C and bake it to solidify the catalyst coating, immerse it in the solution b and let it stand for 15 minutes, then take it out and bake it at 450°C to solidify and pyrolyze the polydimethylsiloxane layer for 30 minutes, then take it out and let it cool naturally.

[0046] Example 2:

[0047] A method for preparing a metal powder felt filter material with catalytic function comprises the following steps:

[0048] Step 1: Cu-SSZ-13 molecular sieve catalyst, nano-alumina, and low-melting-point glass powder are mixed and ball-milled, wherein the mass ratio of Cu-SSZ-13 molecular sieve catalyst, nano-alumina, and low-melting-point glass powder is 2:0.5:0.3, the ball-milling parameter is 500 rpm, and the ball-milling time is 10 min; water and polymethyl methacrylate are added to prepare a mixed slurry a, and the pH is adjusted to 3 with 10 wt % nitric acid solution, wherein the mass ratio of water, polymethyl methacrylate, and catalyst is 1:5:1, and the particle size of polymethyl methacrylate is 50 μm;

[0049] Step 2: applying the mixed slurry a to the surface of the nickel metal powder felt substrate using a 100 μm wire rod coater;

[0050] Step 3: dissolving polydimethylsiloxane and methyltrimethoxysilane in n-pentane, and ultrasonically dispersing for 10 minutes to prepare a solution b containing 5 wt% polydimethylsiloxane, wherein the methyltrimethoxysilane accounts for 0.1 of the mass of the polydimethylsiloxane;

[0051] Step 4: Dry the nickel metal powder felt coating in step 2 at 80°C, then heat it to 500°C and bake it to solidify the catalyst coating, immerse it in the solution b and let it stand for 15 minutes, then take it out and bake it at 450°C to solidify and pyrolyze the polydimethylsiloxane layer for 30 minutes, take it out and let it cool naturally.

[0052] Example 3:

[0053] A method for preparing a metal powder felt filter material with catalytic function comprises the following steps:

[0054] Step 1: Cu-ZSM-5 molecular sieve catalyst, kaolin, and low-melting point glass powder are mixed and ball-milled, wherein the mass ratio of Cu-ZSM-5 molecular sieve catalyst, kaolin, and low-melting point glass powder is 2:0.5:0.2, the ball milling parameter is 500 rpm, and the ball milling time is 10 min; water and polymethyl methacrylate are added to prepare a mixed slurry a, and the pH is adjusted to 3 with 10 wt% nitric acid solution, wherein the mass ratio of water, polymethyl methacrylate, and catalyst is 1.5:6:1, and the particle size of polymethyl methacrylate is 50 μm;

[0055] Step 2: Apply the mixed slurry a to the surface of the Fe / Al metal powder felt substrate using a 200 μm wire rod coater;

[0056] Step 3: dissolving polydimethylsiloxane and methyltrimethoxysilane in toluene, and ultrasonically dispersing for 10 minutes to prepare a solution b containing 5 wt% polydimethylsiloxane, wherein the methyltrimethoxysilane accounts for 0.1 of the mass of the polydimethylsiloxane;

[0057] Step 4: Dry the Fe / Al metal powder felt coating in step 2 at 80°C, then heat it to 500°C and bake it to solidify the catalyst coating, immerse it in the solution b and let it stand for 15 minutes, then take it out and bake it at 450°C to solidify and pyrolyze the polydimethylsiloxane layer for 30 minutes, then take it out and let it cool naturally.

[0058] Detection method description: In all examples, NO x The effective removal rate of NO in the flue gas before and after the reaction was tested by the flue gas automatic tester. x The effective removal efficiency and NO content of the catalytic filter material can be calculated. x The removal efficiency was defined as the ratio of the difference between the NO concentration at the inlet of the catalytic reaction and the NO concentration in the tail gas at the outlet to the NO concentration at the inlet, where the reaction conditions were set as T = 300 °C, NO = 400 ppm, NH3 / NO = 1, O2 = 3% vol, and N2 = 890 mL / min.

[0059] The air permeability test of the filter material is to test the air permeability of the filter material through an air permeability tester.

[0060] The filtration performance of the filter material is tested using the VDI dust filtration efficiency test system, where the filtration efficiency of the filter material is tested by measuring the dust concentration before and after filtration to calculate the filtration efficiency. The filtration efficiency of the catalytic filter material is the ratio of the difference between the dust concentration and the emission concentration of the VDI dust filtration efficiency test system to the dust concentration. The resistance of the filter material is tested using the VDI dust filtration efficiency test system to test the resistance of the filter material before and after filtration to obtain the initial resistance and residual resistance of the filter material. The shedding rate of the filter material is tested using the spraying function of the VDI dust filtration efficiency test system to test the mass change of the coating before and after spraying 10,000 times to calculate the shedding rate.

[0061] The filter material loading capacity test is carried out by weighing the filter material before and after the loading test, calculating the weight difference and converting it into grams per square meter, which is used as the catalyst loading capacity of the catalytic filter material.

[0062] The metal powder felt catalytic filter material prepared by the traditional impregnation method catalytically degrades NO x , air permeability test and catalyst loading firmness test as the control group, the specific experimental process is as follows: take a certain mass of molecular sieve catalyst particles, ball-mill and disperse them in deionized water, prepare a slurry of a certain mass concentration, immerse the metal powder felt in it for full adsorption, take out, dry and calcine (the control group of Example 1: the mass concentration of Fe-ZSM-5 molecular sieve slurry is 20wt%, the immersion time is 30min, the drying temperature is 80℃, and the calcination temperature is 500℃; the control group of Example 2: the mass concentration of Cu-SSZ-13 molecular sieve slurry is 20wt%, the immersion time is 30min, the drying temperature is 80℃, and the calcination temperature is 500℃; the control group of Example 3: the mass concentration of Cu-ZSM-5 molecular sieve slurry is 20wt%, the immersion time is 30min, the drying temperature is 80℃, and the calcination temperature is 500℃). The NO in the control group x The removal performance test and the evaluation process of the air permeability and loading performance of the catalytic filter material were the same as those in Examples 1-3, and other experimental conditions were also kept consistent.

[0063] Figure 1 、 Figure 2 and Figure 3 The following are surface scanning electron micrographs of a blank powder felt, Example 1, and a metal powder felt catalytic filter material (control group) prepared by the traditional impregnation method corresponding to Example 1. It can be seen that compared to the metal powder felt catalytic filter material prepared by the traditional impregnation method, the metal powder felt catalytic filter material of Example 1 retains more pores on its surface, while the pores of the catalytic filter material of the control group are severely clogged, indicating that the traditional impregnation method is not suitable for loading molecular sieve catalysts on metal powder felt filter materials.

[0064] Table 1 compares the performance parameters of blank powder felt, Example 1, and the metal powder felt catalytic filter material prepared by the traditional impregnation method corresponding to Example 1 (control group). Compared with the control group of Example 1, the catalytic filter material prepared by Example 1 better retains the air permeability of the metal powder felt. However, due to the insufficient loading of the metal powder felt catalytic filter material prepared by the traditional impregnation method, it is impossible to obtain the ideal NO x The effective removal rate is 2.3%, and it can be found that the loading scheme proposed by the present invention has excellent loading strength for the catalyst, and can withstand 10,000 injection tests with a shedding rate of 0. Compared with the blank metal powder felt, the metal powder felt catalytic filter material prepared in Example 1 has a certain increase in resistance, but the emission concentration and filtration efficiency are also correspondingly improved. This shows that the loading scheme proposed by the present invention does not significantly affect the filter material itself and has broad application prospects in the field of high-temperature dust removal and denitrification.

[0065] Table 1 Performance parameters of blank powder felt, Example 1, and the metal powder felt catalytic filter material prepared by the traditional impregnation method corresponding to Example 1 (control group)

[0066]

[0067] Figure 4 and Figure 5 These are cross-sectional scanning electron microscope images of a blank powder felt and Example 1, respectively. The molecular sieve denitration catalyst coating itself is bonded together, and the coating deeply penetrates into the metal powder felt substrate to form an integral catalyst with the substrate.

[0068] Figure 6 、 Figure 7 and Figure 8 The catalytic denitrification efficiency, air permeability and shedding rate comparison of the catalytic filter materials prepared in Examples 2-3 and the corresponding control group are shown in the figure. It can be seen that compared with the traditional impregnation method, the catalytic filter material prepared by the scheme used in the present invention has higher catalytic denitrification efficiency and air permeability due to its high loading capacity, good air permeability and good loading firmness. When tested at 300℃, the denitrification efficiency of the experimental group increased by more than 50%, and the air permeability was 20L / dm 2 ·min or more, and the shedding rate is 0. These data results are basically consistent with those in Example 1. The above data also show that the metal powder felt filter material with catalytic function prepared by the present invention has good catalytic denitrification efficiency and air permeability, which improves the problems of low catalyst loading and poor air permeability of the catalytic filter material prepared by the traditional impregnation method.

[0069] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A metal powder felt filter material with catalytic function, characterized by: The invention comprises a metal powder felt substrate and a molecular sieve catalyst layer; the molecular sieve catalyst layer is loaded on the surface of the metal powder felt substrate and partially penetrates into the interior of the metal powder felt substrate; the molecular sieve catalyst layer is composed of a catalyst, a binder, a structural additive, a pore-forming agent and a polydimethylsiloxane solution; the catalyst is one of Fe-ZSM-5, Cu-ZSM-5 and Cu-SSZ-13; the binder is at least one of nano-alumina and kaolin; the structural additive is a low-melting-point glass powder; the pore-forming agent is at least one of polymethyl methacrylate, polyvinyl pyrrolidone and citric acid; and the solvent of the polydimethylsiloxane is one of n-hexane, n-pentane and toluene.

2. The metal powder felt filter material according to claim 1, characterized in that: The metal powder felt is one of stainless steel powder felt, nickel alloy powder felt, and Fe / Al powder felt, and has a three-dimensional porous structure, a porosity of 20-60%, and a pore size of 5-15 μm.

3. The metal powder felt filter material according to claim 1, characterized in that: The thickness of the metal powder felt substrate is 200-400 μm, and the thickness of the molecular sieve catalyst layer is 50-100 μm.

4. A method for preparing the metal powder felt filter material with catalytic function according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: mixing and ball-milling the catalyst, the binder, and the structural additive, wherein the mass ratio of the binder, the structural additive, and the catalyst is 0.1-1:0.1-0.3:1; adding water and a pore-forming agent to prepare a mixed slurry a, and adjusting the pH to 2-4, wherein the mass ratio of water, the pore-forming agent, and the catalyst is 1-1.5:3-5:1; Step 2: applying the mixed slurry a to the surface of the metal powder felt substrate; Step 3: Dissolve polydimethylsiloxane and a curing agent in a solvent, fully stir or ultrasonically disperse, and prepare a solution b with a polydimethylsiloxane mass fraction of 5 to 10 wt%, wherein the mass ratio of the curing agent to the polydimethylsiloxane is 0.1:1; Step 4: Dry the metal powder felt obtained in step 2, heat it to 400-700°C for curing, immerse it in solution b and let it stand; take it out, cure it at 350-500°C, pyrolyze it, take it out and let it cool naturally to obtain the metal powder felt filter material with catalytic function.

5. The method according to claim 4, characterized in that: In step 1, the pH of the mixed slurry a is adjusted with a 10 wt % nitric acid solution.

6. The method according to claim 4, characterized in that: In step 1, the ball milling speed is 350-550 rpm and the time is 10-30 min.

7. The method according to claim 4, characterized in that: The coating method of step 2 is knife coating.

8. The method according to claim 4, wherein: The curing agent in step 3 is methyltrimethoxysilane or ethyl orthosilicate, and the stirring or ultrasonication time is more than 10 minutes.

9. The method according to claim 4, wherein: The drying temperature in step 4 is 60-100°C, the drying time is 50-100 min, and the curing time is more than 10 min.

10. Use of the metal powder felt filter material with catalytic function as claimed in any one of claims 1 to 3 or the metal powder felt filter material with catalytic function obtained by the method according to any one of claims 4 to 9 in the preparation of an integrated material for high-temperature flue gas dust removal and denitrification.

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