Corrugated plate denitration catalyst, preparation method and application thereof

Abstract

The application provides a corrugated plate type denitration catalyst and a preparation method and application thereof, and the preparation method comprises the following steps: mixing a titanium source, a cerium source, nano-alumina, acetylacetone, ethanol and water to obtain a mixed solution, adjusting the pH to 1-5, and obtaining an intermediate after first drying and first calcination; performing alkali dissolution treatment on the intermediate by using an alkali solution to obtain an alkali dissolution product; mixing the alkali dissolution product, a copper source, a manganese source, a dispersing agent, a binder and a pore-forming agent, adjusting the pH to 7-12, and obtaining a mud; stamping and forming the mud to obtain corrugated sheets; spraying resin glue between a plurality of the corrugated sheets, and then layering and assembling to obtain a corrugated plate type denitration catalyst blank; and firing the corrugated plate type denitration catalyst blank to obtain the corrugated plate type denitration catalyst. By regulating and controlling the dispersity of active components, the prepared catalyst has the advantages of large specific surface area, high catalytic activity, and the like, and is especially suitable for a denitration environment with high air speed.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to a corrugated plate denitrification catalyst, its preparation method, and its application. Background Technology

[0002] With the rapid development of my country's economy and industrial production, nitrogen oxide (NOx) emissions have also increased. NOx causes pollution such as photochemical smog and the greenhouse effect, seriously endangering human health. To promote the comprehensive development of emission reduction technologies, how to reduce the generation and emission of NOx has become one of the main concerns.

[0003] Selective catalytic reduction (SCR) refers to the reaction of a reducing agent with NOx in flue gas under the action of a catalyst to produce non-toxic and pollution-free N2 and H2O. It is a relatively mature NOx purification method. Among them, the SCR technology using ammonia as a reducing agent (NH3-SCR) is widely used in the emission control of NOx from industrial stationary sources. However, ammonia is prone to leakage during production, storage, transportation, and use, causing secondary pollution. More seriously, it can cause combustion, explosion, or poisoning accidents, posing certain dangers. Ammonia can also corrode pipelines. If the flue gas temperature is low, ammonia can also react with sulfur oxides in the flue to form ammonium sulfate, thereby clogging the flue. Therefore, it is necessary to find an economical, long-lasting, environmentally friendly, and safe denitrification technology.

[0004] Currently, industrial flue gas contains a large amount of CO. For example, the CO concentration in the tail gas of ethylene cracking furnaces is much higher than the NOx concentration. CO can be used as a reducing agent for SCR denitrification without the need for additional reducing agents. This not only saves on material consumption associated with adding NH3 and avoids the safety hazards associated with NH3 transportation and storage, but also achieves waste-to-waste treatment, reducing costs. However, due to space limitations in ethylene cracking furnaces and gas-fired boilers, high-reaction-space-velocity denitrification catalysts are required to meet denitrification requirements.

[0005] Currently, catalysts are often processed into honeycomb-shaped catalysts with a higher pore count to increase their external specific surface area. However, as the pore count of honeycomb catalysts increases, higher demands are placed on the molds. Furthermore, with the increased pore count, cracks or adhesion to the mold are more likely to occur during extrusion, resulting in low molding yield, low mechanical strength, wasted manufacturing resources, and increased costs. Therefore, how to provide a denitrification catalyst with high reaction space velocity and good stability is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing a corrugated plate denitrification catalyst. By improving the dispersibility of the active components, the prepared catalyst has the advantages of high reaction space velocity, high catalytic activity, and good stability. It also has the advantages of simple preparation process and easy operation.

[0007] The present invention also provides a corrugated plate denitrification catalyst, which has the advantages of high reaction space velocity and high catalytic activity.

[0008] The present invention also provides a flue gas denitrification method, which uses the above-mentioned corrugated plate denitrification catalyst to treat the flue gas for denitrification. This method can not only make full use of carbon monoxide in the flue gas, but also has the advantages of high denitrification efficiency and good stability, effectively reducing pollutant emissions.

[0009] In one aspect, the present invention provides a method for preparing a corrugated plate type denitrification catalyst, comprising the following steps:

[0010] Titanium source, cerium source, nano alumina, acetylacetone, ethanol and water are mixed to obtain a mixture, the pH is adjusted to 1-5, and after a first drying and a first calcination, an intermediate is obtained;

[0011] The intermediate was subjected to alkaline dissolution with an alkaline solution to obtain the alkaline-soluble product.

[0012] The alkali-soluble product, copper source, manganese source, dispersant, binder, and pore-forming agent are mixed, and the pH is adjusted to 7-12 to obtain mud.

[0013] The mud material is stamped into corrugated sheets; resin adhesive is sprayed between several corrugated sheets and then stacked and assembled to obtain a corrugated plate type denitrification catalyst blank.

[0014] The corrugated plate denitrification catalyst blank is sintered to obtain a corrugated plate denitrification catalyst.

[0015] According to one embodiment of the present invention, each of the corrugated sheets has a thickness of 0.2 to 0.6 mm, a width of 4 to 8 mm, and a height of 4 to 10 mm.

[0016] According to one embodiment of the present invention, the firing conditions are: under a nitrogen atmosphere, at a temperature of 400–680°C, for a time of 2–40 h.

[0017] According to one embodiment of the present invention, the titanium source includes at least one of tetrabutyl titanate and titanium isopropoxide; and / or,

[0018] The volume ratio of ethanol, acetylacetone, and titanium source is (3-20):(0.01-0.1):1; and / or,

[0019] The cerium source includes at least one of cerium nitrate, cerium sulfate, and cerium chloride; and / or,

[0020] The mass ratio of the cerium source to the titanium source is (5-20):100, and / or,

[0021] The mass ratio of the nano-alumina to the titanium source is (0.5-5):100, wherein the mass of the cerium source is calculated as CeO2, the mass of the titanium source is calculated as TiO2, and the mass of the nano-alumina is calculated as Al2O3.

[0022] According to one embodiment of the present invention, the temperature of the first drying is 60°C-180°C, and the time is 5h-50h;

[0023] The first roasting temperature is 400℃-680℃, and the time is 2h-35h.

[0024] According to one embodiment of the present invention, the solute of the alkaline solution includes at least one of sodium hydroxide and potassium hydroxide;

[0025] The concentration of the alkaline solution is 0.1 mol / L to 5.0 mol / L, and the volume ratio of the alkaline solution to the intermediate is (0.5-8):1.

[0026] According to one embodiment of the present invention, the copper source includes at least one of copper nitrate, copper sulfate, and copper chloride;

[0027] The mass ratio of the copper source to the titanium source is (1-10):100;

[0028] The manganese source includes at least one of manganese nitrate, manganese sulfate, manganese chloride, and manganese chlorate;

[0029] The mass ratio of the manganese source to the titanium source is (2-15):100; wherein the mass of the copper source is CuO, the mass of the titanium source is TiO2, and the mass of the manganese source is MnO2.

[0030] According to one embodiment of the present invention, the dispersant includes at least one of polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, wherein the mass ratio of the dispersant to the titanium source is (0.2-3):100;

[0031] The binder includes at least one of carboxymethyl cellulose and hydroxypropyl cellulose, and the mass ratio of the binder to the titanium source is (1-10):100.

[0032] The pore-forming agent includes at least one of polyethylene oxide, polymethyl methacrylate, and guar gum powder; the mass ratio of the pore-forming agent to the titanium source is (0.2-2):100.

[0033] In a second aspect, the present invention provides a corrugated plate denitrification catalyst, which is prepared by the above-described preparation method.

[0034] A third aspect of the present invention provides a flue gas denitrification method, wherein the flue gas is treated with the above-mentioned corrugated plate denitrification catalyst, wherein the flue gas contains carbon monoxide and nitrogen oxides.

[0035] The implementation of this invention has at least the following beneficial effects:

[0036] (1) The preparation method of the corrugated plate denitration catalyst provided by the present invention uses the sol-gel method to incorporate cerium (Ce) into the titanium dioxide (TiO2) lattice, causing TiO2 lattice defects. The lattice defects are conducive to the generation of oxygen vacancies, which increases the number of oxygen vacancies on the catalyst surface, increases the acid sites on the catalyst surface, and is conducive to improving the activity.

[0037] (2) The preparation method of the corrugated plate denitrification catalyst provided by the present invention adopts calcination followed by alkaline dissolution treatment. After calcination, the lattice defects are more stable. After the alkaline solution dissolves the nano alumina, it greatly increases the lattice defects and specific surface area of ​​the substrate. After the manganese and copper are added, it is more conducive to the dispersion of active components. In addition, after the alkaline solution dissolves the nano alumina, the lattice defects and spaces formed are more likely to contact the surface position of the flue gas in the flue gas atmosphere, which is conducive to increasing the reaction space velocity and improving the denitrification effect under the same conditions.

[0038] (3) The preparation method of the corrugated plate denitration catalyst provided by the present invention involves adding copper and manganese elements after alkali dissolution treatment. Due to the presence of many lattice defects, copper and manganese elements fill the gaps. After calcination, the lattice defects of the doped substrate are more stable, which is conducive to maintaining high denitration activity of the catalyst.

[0039] (4) In the preparation method provided by the present invention, copper and cerium elements are added to the active components of the catalyst, which can work synergistically with manganese to improve the competition of oxygen and nitrogen oxides for carbon monoxide, so that carbon monoxide preferentially undergoes catalytic reduction reaction with nitrogen oxides.

[0040] The corrugated plate denitrification catalyst provided by this invention features an increased external specific surface area, high molding rate, low manufacturing cost, convenient transportation, low breakage rate, reduced catalyst loading space, and lower infrastructure investment costs. Furthermore, this invention uses CO as the SCR denitrification reducing agent. When applied to the denitrification of ethylene cracking furnace flue gas, it achieves the effect of treating waste with waste, eliminating the need for additional reducing agent and reducing the safety risks associated with NH3-SCR denitrification. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0042] The preparation method of the corrugated plate denitrification catalyst provided by the present invention includes the following steps:

[0043] Titanium source, cerium source, nano alumina, acetylacetone, ethanol and water are mixed to obtain a mixture, the pH is adjusted to 1-5, and after a first drying and a first calcination, an intermediate is obtained;

[0044] The intermediate was subjected to alkaline dissolution with an alkaline solution to obtain the alkaline-soluble product.

[0045] The alkali-soluble product, copper source, manganese source, dispersant, binder, and pore-forming agent are mixed and the pH is adjusted to 7-12 to obtain mud.

[0046] The mud is stamped into corrugated sheets; resin adhesive is sprayed between several corrugated sheets and then stacked and assembled to obtain a corrugated plate type denitrification catalyst blank.

[0047] The corrugated plate denitrification catalyst blank was sintered to obtain the corrugated plate denitrification catalyst.

[0048] The method for preparing the corrugated plate denitration catalyst provided by this invention involves first incorporating cerium (Ce) into the titanium dioxide (TiO2) lattice using a sol-gel method, while simultaneously encapsulating nano-alumina within the titanium dioxide. Then, an alkaline solution is used for alkali dissolution to remove the nano-alumina, yielding an alkali-dissolved product. Finally, the alkali-dissolved product is mixed with copper and manganese sources to form a slurry. The slurry is then pressed into corrugated sheets. After stacking several corrugated sheets, a corrugated plate denitration catalyst is obtained through firing. This method allows copper and manganese oxides to be loaded onto a cerium-doped titanium dioxide support. This corrugated plate denitration catalyst exhibits advantages such as high reaction space velocity, high catalytic activity, and high stability.

[0049] The inventors, through research and analysis, believe that by mixing titanium source, cerium source, nano-alumina, acetylacetone, ethanol, and water, followed by a first drying and a first calcination, cerium (Ce) is incorporated into the titanium dioxide (TiO2) lattice, creating lattice defects that facilitate the generation of oxygen vacancies. Simultaneously, it allows the nano-alumina to be encapsulated within the titanium dioxide. Alkaline dissolution of the intermediate with an alkaline solution dissolves the nano-alumina, significantly increasing the lattice defects and specific surface area of ​​the intermediate. Sufficient contact between the alkaline dissolution product and the copper and manganese sources allows the active components manganese and copper to fill the lattice defects, further improving their dispersion. In this preparation process, the active components cerium, manganese, and copper oxides are uniformly loaded onto the titanium dioxide support, which is beneficial for improving the catalytic activity of the catalyst, making it suitable for a volume hourly space velocity (VHSV) of 11000 h⁻¹. -1 The conditions are particularly suitable for denitrification environments requiring higher air velocities.

[0050] In one embodiment of the present invention, the titanium source includes at least one selected from tetrabutyl titanate, titanium sulfate, titanium isopropoxide, and titanium tetrachloride. The volume ratio of ethanol to the titanium source is (3-20):1, preferably (5-10):1. Ethanol enables the titanium source to form titanium hydroxide in solution A, which is beneficial for the formation of titanium dioxide crystals after subsequent calcination. The volume ratio of acetylacetone to the titanium source is (0.01-0.1):1.

[0051] In the above embodiments, the cerium source includes at least one of cerium nitrate, cerium sulfate, and cerium chloride. The mass ratio of the cerium source to the titanium source is (5-20):100, preferably (6-12):10, wherein the mass of the cerium source is based on CeO2 and the mass of the titanium source is based on TiO2.

[0052] In the above embodiments, the nano-alumina can be nano-alumina sol, and the particle size of the nano-alumina can be 1nm-50nm, preferably 1nm-30nm.

[0053] In the above embodiments, the mass ratio of nano-alumina to titanium source is (0.5-5):100, preferably (0.5-2):100, wherein the mass of nano-alumina is calculated as Al2O3.

[0054] In the specific implementation of the present invention, for example, titanium source and acetylacetone can be mixed, and then cerium source, nano alumina and ethanol can be added and mixed and stirred. An acid solution is added to adjust the pH to 1-5 to obtain a mixed solution, wherein the pH value is preferably 2-4.

[0055] In the above embodiments, adjusting the pH to 1-5 can be achieved by adding hydrochloric acid, which can be either dilute or concentrated. Adjusting the pH increases acid sites, which is beneficial for the formation of lattice defects.

[0056] In the specific implementation of this invention, after aging the mixture, it undergoes a first drying and a first calcination to obtain an intermediate.

[0057] In the above embodiments, on the one hand, cerium doping in the titanium dioxide lattice creates lattice defects, which become more stable after the first calcination; on the other hand, nano-alumina encapsulates the titanium dioxide, which helps to form more lattice defects in the future.

[0058] In the above embodiments, mechanical stirring or ultrasonic assistance can be used to achieve uniform diffusion of the mixture. The aging time can be 0.5-10 days, preferably 2-5 days.

[0059] In the above embodiments, the aging temperature is generally controlled at 10℃-90℃, preferably 20℃-60℃.

[0060] The first drying temperature is 60℃-180℃, preferably 60℃-90℃, and the time is 5h-50h, preferably 8h-30h. The first calcination temperature is 400℃-680℃, preferably 450℃-610℃, and the time is 2h-35h, preferably 3h-20h.

[0061] In this invention, an alkaline solution is used to dissolve the intermediate. The alkaline solution can dissolve the nano-alumina in the intermediate, forming lattice defects, which further increases the lattice defects and specific surface area.

[0062] In the above embodiments, the solute of the alkaline solution includes at least one of sodium hydroxide and potassium hydroxide, the concentration of the alkaline solution is 0.1 mol / L-5.0 mol / L, and the volume ratio of the alkaline solution to the intermediate is (0.5-8):1, preferably (0.8-3):1.

[0063] In the above embodiments, the solid produced after alkali dissolution is further washed. Deionized water can be used as the washing liquid, and the washing is preferably repeated 3-5 times. Then, the product is obtained by filtration.

[0064] In this invention, alkali-soluble products, copper sources, manganese sources, dispersants, binders, and pore-forming agents are mixed to form a slurry. The slurry is first stamped to form corrugated sheets. Several corrugated sheets are then sprayed with resin adhesive and stacked together to obtain a corrugated plate-type denitrification catalyst blank, which enhances structural stability. The denitrification catalyst blank is then sintered. Since the alkali-soluble products have more lattice defects, the copper and manganese sources can fill the lattice defects, which is beneficial to improving the dispersibility of the active components.

[0065] In the above embodiments, the dispersant includes at least one of polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and the mass ratio of the dispersant to the titanium source is (0.2-3):100. The molecular weight of polyethylene glycol can be 400-10000, preferably 1500-2000.

[0066] In the above embodiments, the binder includes at least one of carboxymethyl cellulose and hydroxypropyl cellulose, and the mass ratio of the binder to the titanium source is (1-10):100, wherein the mass of the titanium source is TiO2. The pore-forming agent includes at least one of polyethylene oxide, polymethyl methacrylate, and guar gum powder; the mass ratio of the pore-forming agent to the titanium source is (0.2-2):100.

[0067] In the above embodiments, the moisture content of the clay is 10%-60%, preferably 20%-40%. Each corrugated sheet has a thickness of 0.2-0.6 mm, a width of 4-8 mm, and a height of 4-10 mm. The resin adhesive is, for example, epoxy resin adhesive.

[0068] In the above embodiments, the firing conditions were: under a nitrogen atmosphere, at a temperature of 400–680°C, for a time of 2–40 hours.

[0069] In the above embodiments, the copper source includes at least one of copper nitrate, copper sulfate, and copper chloride, preferably copper nitrate, and the mass ratio of the copper source to the titanium source is (1-10):100, preferably (2-5):100, wherein the mass of the copper source is based on CuO and the mass of the titanium source is based on TiO2.

[0070] In the above embodiments, the manganese source includes at least one of manganese nitrate, manganese sulfate, manganese chloride, and manganese chlorate, preferably manganese nitrate. The mass ratio of manganese source to titanium source is (2-15):100, preferably (2-6):100, wherein the manganese source is calculated as MnO2 and the titanium source is calculated as TiO2.

[0071] The corrugated plate denitrification catalyst provided by the present invention is prepared by the above-mentioned preparation method. The corrugated plate denitrification catalyst uses titanium dioxide as a support and cerium, manganese and copper as active components of the denitrification catalyst.

[0072] In the above-mentioned corrugated plate denitrification catalyst, the mass ratio of titanium dioxide, cerium, manganese and copper is generally equal to the amount of cerium source, titanium source, manganese source and copper source used in its preparation process.

[0073] In the aforementioned corrugated plate denitrification catalyst, cerium is doped into the titanium dioxide lattice, and manganese and copper oxides are supported on the titanium dioxide support. The active components cerium, manganese, and copper are uniformly dispersed on the titanium dioxide support, and cerium, manganese, and copper play a synergistic role, enabling carbon monoxide to preferentially undergo catalytic reduction reaction with nitrogen oxides, thereby improving denitrification efficiency. This corrugated plate denitrification catalyst has advantages such as strong stability, high reaction space velocity, and high catalytic activity. When used in flue gas denitrification, it can increase the contact area between flue gas and catalyst, improve denitrification efficiency and denitrification stability. In addition, the doping of cerium improves the catalyst's resistance to alkali metal poisoning and alkaline earth metal poisoning.

[0074] The flue gas denitrification method provided by the present invention uses the above-mentioned corrugated plate denitrification catalyst to denitrify the flue gas, wherein the flue gas contains carbon monoxide and nitrogen oxides.

[0075] The flue gas denitrification method provided by the present invention uses carbon monoxide in the flue gas as a reducing agent and the above-mentioned corrugated plate denitrification catalyst as a catalyst for SCR denitrification. The specific process includes: placing the corrugated plate denitrification catalyst in a reactor, introducing a mixed gas containing oxygen and nitrogen, and heating it to 330℃-350℃, while simultaneously introducing flue gas to ensure that the flue gas and the catalyst are in full contact for denitrification treatment.

[0076] In the above embodiments, the flue gas also contains SO2, and nitrogen oxides include NO. The denitrification treatment using the catalyst provided by this invention exhibits high denitrification stability, low cost, and high catalytic activity. It is particularly suitable for denitrification environments requiring high space velocity, and the active components in the catalyst work synergistically, enabling carbon monoxide in the flue gas to preferentially undergo catalytic reduction reactions with nitrogen oxides, thereby improving denitrification efficiency.

[0077] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0078] In all the examples and comparative examples, all other chemicals used were commercially available chemically pure reagents. The catalysts prepared in the examples and comparative examples were evaluated using the following assay methods:

[0079] (1) Specific surface area

[0080] The specific surface area of ​​the sample was determined using the BET adsorption method.

[0081] (2) Denitrification efficiency

[0082] Using the catalysts prepared in the examples and comparative examples as denitrification catalysts, the flue gas was denitrified according to the following flue gas denitrification method:

[0083] The catalyst is placed in a fixed-bed reactor, a mixture of oxygen and nitrogen is introduced, and the temperature is raised to 360°C. At the same time, flue gas is introduced to ensure that the flue gas and the catalyst are in full contact for denitrification. The concentration of each component in the flue gas and tail gas is measured by a flue gas analyzer. The NOx conversion rate is calculated as (NOx concentration in flue gas - NOx concentration in tail gas) / NOx concentration in flue gas.

[0084] The flue gas analyzer is a Siemens ULTRAMAT23 continuous online flue gas analyzer; the content of each component in the flue gas is as follows: carbon monoxide (CO) is 400 mg / Nm³. 3 Nitric oxide (NO) concentration was 400 mg / Nm³. 3 A standard gas meter was used. The O2 content in the reactor was 3% (v), and the NO and CO contents were both 5% (v). Nitrogen was used as a balance gas. The NO, CO, and N2 were all produced by Dalian Date Gas Co., Ltd. The O2 came from the public utility air pipeline network at a pressure of 0.4-0.6 MPa, and the N2 came from the public utility nitrogen pipeline network with a purity of 99.0% (v) and a pressure of 0.4-0.6 MPa.

[0085] Reaction conditions: Volume hourly space velocity (VHSV) of 11000 h⁻¹ -1 Temperature 360℃;

[0086] The evaluation results are shown in Table 1.

[0087] Example 1

[0088] 100 g of tetrabutyl titanate (based on TiO2) was dissolved in 10 times its volume of anhydrous ethanol. Then, 2.0 g of nano-aluminum sol (based on Al2O3), 5 mL of acetylacetone, and 8.0 g of cerium nitrate (based on CeO2) were added. The pH of the material was adjusted to 2.0 with nitric acid. After ultrasonic post-treatment, the resulting gel material was aged at room temperature for 3 days, dried at 70°C for 20 hours, and then calcined in a muffle furnace at 450°C for 20 hours. The resulting solid was ground and soaked and washed in 1.0 times its volume of 0.1 mol / L sodium hydroxide solution. Filtering yields a filter cake; the filter cake is then mixed with 2.0g copper nitrate (calculated as CuO), 2.0g manganese nitrate (calculated as MnO2), 8.0g carboxymethyl cellulose, 1.0g polyvinylpyrrolidone, and 0.3g polymethyl methacrylate in deionized water and mechanically stirred to form a mud with a water content of 15%. The pH is adjusted to 8.0, and corrugated plates are stamped out. Epoxy resin is sprayed between the corrugated plates and then stacked to obtain a corrugated plate denitrification catalyst blank. After drying, the blank is calcined at 520℃ for 12 hours according to the heating program to obtain a corrugated plate CO-SCR denitrification catalyst.

[0089] The above-obtained catalyst NO x Conversion rate 75.3%, specific surface area 58m²2 / g.

[0090] Comparative Example 1

[0091] The catalyst preparation method disclosed in patent document CN106552652A specifically includes: adding 5 ml of acetylacetone to 100 g of tetrabutyl titanate, then adding 8.0 g of cerium nitrate (based on CeO2) and 10 times the volume of ethanol solution of tetrabutyl titanate, stirring to obtain a sol, drying and calcining the sol to obtain a cerium-doped titanium oxide support; impregnating the obtained cerium-doped titanium oxide support in an aqueous solution of 2.0 g of copper nitrate (based on CuO), drying and calcining to obtain Ce-doped CuO / TiO2; impregnating the obtained Ce-doped CuO / TiO2 in an aqueous solution of 2.0 g of MnO2... Ce-doped Cu-MnO2 / TiO2 catalyst was obtained by drying and calcining in 0.0g of manganese nitrate aqueous solution. Then, 8.0g of carboxymethyl cellulose, 1.0g of polyvinylpyrrolidone, and 0.3g of polymethyl methacrylate were added to deionized water and mechanically stirred to prepare a mud with a water content of 15%. The pH value was adjusted to 8.0, and corrugated plates were stamped out. After spraying epoxy resin between the corrugated plates, they were stacked and assembled to obtain a corrugated plate denitrification catalyst blank. After drying the blank, it was calcined at 520℃ for 12h according to the heating program to obtain a corrugated plate CO-SCR denitrification catalyst.

[0092] The obtained catalyst NO x Conversion rate 69.7%, specific surface area 44m² 2 / g.

[0093] Example 2

[0094] 100g of tetrabutyl titanate (based on TiO2) was dissolved in 5 times its volume of anhydrous ethanol. Then, 1.0g of nano-aluminum sol (based on Al2O3), 4ml of acetylacetone, and 12.0g of cerium nitrate (based on CeO2) were added. The pH of the material was adjusted to 3.0 with nitric acid. After ultrasonic treatment, the resulting gel material was aged at room temperature for 4 days, then dried at 90℃ for 12 hours, and then calcined in a muffle furnace at 450℃ for 7 hours. The resulting solid was ground and soaked in 1.2 times its volume of 2.0mol / L sodium hydroxide solution. The filter cake was obtained by washing and filtering. The filter cake was then mixed with 3.0g copper sulfate (calculated as CuO), 10.0g manganese nitrate (calculated as MnO2), 7.0g carboxymethyl cellulose, 0.8g polyethylene glycol, and 1.0g polyoxyethylene in deionized water and mechanically stirred to form a mud with a water content of 25%. The pH was adjusted to 10.0, and corrugated plates were stamped out. Epoxy resin was sprayed between the corrugated plates and then stacked to obtain a corrugated plate denitrification catalyst blank. After drying, the blank was calcined at 550℃ for 8 hours to obtain a corrugated plate CO-SCR denitrification catalyst.

[0095] The catalyst obtained above has a NOx conversion rate of 84.5% and a specific surface area of ​​64 m². 2 / g.

[0096] Comparative Example 2

[0097] CN111229212B discloses a CO-SCR denitrification catalyst, its preparation method, and its application. Specifically, the process includes: dissolving 3.0 g of copper sulfate (based on CuO) and 10.0 g of manganese nitrate (based on MnO2) in deionized water, then stirring at 70°C for 60 min to obtain a mixed salt solution A. A certain amount of Na2CO3 is dissolved in deionized water to prepare an alkaline precipitant solution. Under stirring at 40°C, the Na2CO3 alkaline precipitant is added dropwise to the mixed solution B and stirred until the pH of the mixed solution reaches 8, yielding a mixture C. Mixture C is allowed to stand at room temperature for 2 h for aging, then filtered and repeatedly washed with deionized water until the filtrate pH reaches 7, yielding a filter cake D. Filter cake D is ball-milled at 420 r / min for 120 min to obtain powder E. Powder E is dried in an oven at 110°C for 12 h, and finally calcined and activated in a muffle furnace at 500°C for 5 h to prepare the denitrification catalyst.

[0098] The obtained catalyst achieved a NOx conversion rate of 26.5% and a specific surface area of ​​52 m². 2 / g.

[0099] Example 3

[0100] 100g of tetrabutyl titanate (based on TiO2) was dissolved in 7 times its volume of anhydrous ethanol. Then, 0.5g of nano-alumina (based on Al2O3), 8ml of acetylacetone, and 6.0g of cerium nitrate (based on CeO2) were added. The pH of the material was adjusted to 4.0 with nitric acid. After ultrasonic treatment, the resulting gel was aged at room temperature for 5 days, then dried at 80℃ for 20 hours, and finally calcined in a muffle furnace at 450℃ for 6 hours. The resulting solid was ground, and 2.0 times its volume of 1.5mol / L sodium hydroxide solution was added. The filter cake was soaked, washed, and filtered. It was then mixed with 5.0g copper nitrate (calculated as CuO), 4.0g manganese chloride (calculated as MnO2), 1.6g carboxymethyl cellulose, 1.6g polyvinylpyrrolidone, and 1.0g polyoxyethylene in deionized water and mechanically stirred to form a mud with a water content of 25%. The pH was adjusted to 9.0, and corrugated plates were stamped out. Epoxy resin was sprayed between the corrugated plates and then stacked to obtain a corrugated plate denitrification catalyst blank. After drying, the blank was calcined at 600℃ for 5 hours to obtain a corrugated plate CO-SCR denitrification catalyst.

[0101] The above-obtained catalyst NO x Conversion rate 81.6%, specific surface area 59m²2 / g.

[0102] Example 4

[0103] 100g of titanium isopropoxide (based on TiO2) was dissolved in 6 times its volume of anhydrous ethanol. Then, 1.5g of nano-aluminum sol (based on Al2O3), 7ml of acetylacetone, and 12.0g of cerium sulfate (based on CeO2) were added. The pH of the mixture was adjusted to 3.0 with nitric acid. After mechanical stirring, the resulting gel was aged at room temperature for 3 days, then dried at 85℃ for 14 hours, and finally calcined in a muffle furnace at 500℃ for 6 hours. The resulting solid was ground, and 1.0 times its volume of 2.0mol / L sodium hydroxide solution was added. The filter cake was obtained by soaking, washing, and filtering in liquid. The filter cake was then mixed with 5.0g copper sulfate (calculated as CuO), 8.0g manganese chloride (calculated as MnO2), 5.0g hydroxypropyl cellulose, 1.5g polyethylene glycol, and 1.0g guar gum powder in deionized water and mechanically stirred to form a mud with a water content of 30%. The pH was adjusted to 9.0, and corrugated plates were stamped out. Epoxy resin was sprayed between the corrugated plates and then stacked to obtain a corrugated plate denitrification catalyst blank. After drying the blank, it was calcined at 560℃ for 10 hours according to the heating program to obtain the corrugated plate CO-SCR denitrification catalyst.

[0104] The above-obtained catalyst NO x Conversion rate 83.7%, specific surface area 65m² 2 / g.

[0105] Example 5

[0106] 100g of titanium isopropoxide (based on TiO2) was dissolved in 8 times its volume of anhydrous ethanol. Then, 2.0g of nano-aluminum sol (based on Al2O3), 6ml of acetylacetone, and 6.0g of cerium sulfate (based on CeO2) were added. The pH of the mixture was adjusted to 3.0 with nitric acid. After mechanical stirring, the resulting gel was aged at room temperature for 3 days, then dried at 80℃ for 15 hours, and finally calcined in a muffle furnace at 470℃ for 6 hours. The resulting solid was ground, and 1 volume of 3.5mol / L sodium hydroxide solution was added. The filter cake was obtained by soaking, washing, and filtering. The filter cake was then mixed with 5.0g of copper chloride (calculated as CuO), 6.0g of manganese sulfate (calculated as MnO2), 2.0g of carboxymethyl cellulose, 1.0g of polyethylene glycol, 1.5g of guar gum powder, and deionized oil. The mixture was mechanically stirred to prepare a mud material with a moisture content of 35%. The pH value was adjusted to 9.0, and corrugated plates were stamped out. Epoxy resin was sprayed between the corrugated plates and then stacked to obtain a corrugated plate denitrification catalyst blank. After drying, the blank was calcined at 580℃ for 7 hours according to the heating program to obtain a corrugated plate CO-SCR denitrification catalyst.

[0107] The above-obtained catalyst NOx Conversion rate 80.3%, specific surface area 68m² 2 / g.

[0108] The catalyst prepared by the method provided in this invention has a specific surface area of ​​58 m². 2 / g-68m 2 Using this catalyst for flue gas denitrification increases the catalyst's specific surface area, thereby increasing the contact area between the catalyst and the flue gas, achieving a denitrification efficiency of over 75.3%. Furthermore, this catalyst is particularly suitable for reactions with space velocities as high as 11000 h⁻¹. -1 The inventors, through research and analysis, believe that the active components copper, cerium, and manganese work synergistically to enable carbon monoxide in flue gas to preferentially undergo catalytic reduction with nitrogen oxides, thereby improving denitrification efficiency.

[0109] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a corrugated plate type denitration catalyst, characterized in that, Includes the following steps: Titanium source, cerium source, nano alumina, acetylacetone, ethanol and water are mixed to obtain a mixture, the pH is adjusted to 1-5, and after a first drying and a first calcination, an intermediate is obtained. The intermediate was subjected to alkaline dissolution with an alkaline solution to obtain the alkaline-soluble product. The alkali-soluble product, copper source, manganese source, dispersant, binder, and pore-forming agent are mixed, and the pH is adjusted to 7-12 to obtain mud. The mud material is stamped into corrugated sheets; resin adhesive is sprayed between several corrugated sheets and then stacked and assembled to obtain a corrugated plate type denitrification catalyst blank. The corrugated plate denitrification catalyst blank is sintered to obtain a corrugated plate denitrification catalyst; The mass ratio of the cerium source to the titanium source is (5-20): 100, and / or The mass ratio of the nano-alumina to the titanium source is (0.5-5):100, wherein the mass of the cerium source is calculated as CeO2, the mass of the titanium source is calculated as TiO2, and the mass of the nano-alumina is calculated as Al2O3. The mass ratio of the copper source to the titanium source is (1-10):100; The mass ratio of the manganese source to the titanium source is (2-15):100; wherein the mass of the copper source is CuO, the mass of the titanium source is TiO2, and the mass of the manganese source is MnO2.

2. The preparation method according to claim 1, characterized in that, Each corrugated sheet has a thickness of 0.2~0.6mm, a width of 4~8mm, and a height of 4~10mm.

3. The preparation method according to claim 1, characterized in that, The firing conditions are: under a nitrogen atmosphere, at a temperature of 400~680℃, for a time of 2~40h.

4. The preparation method according to claim 1, characterized in that, The titanium source includes at least one of tetrabutyl titanate and titanium isopropoxide; and / or, The volume ratio of ethanol, acetylacetone, and titanium source is (3-20):(0.01~0.1):1; and / or, The cerium source includes at least one of cerium nitrate, cerium sulfate, and cerium chloride.

5. The preparation method according to any one of claims 1-4, characterized in that, The first drying temperature is 60℃-180℃, and the time is 5h-50h; The first roasting temperature is 400℃-680℃, and the time is 2h-35h.

6. The preparation method according to any one of claims 1-5, characterized in that, The solute in the alkaline solution includes at least one of sodium hydroxide and potassium hydroxide; The concentration of the alkaline solution is 0.1 mol / L to 5.0 mol / L, and the volume ratio of the alkaline solution to the intermediate is (0.5-8):

1.

7. The preparation method according to any one of claims 1-6, characterized in that, The copper source includes at least one of copper nitrate, copper sulfate, and copper chloride; The manganese source includes at least one of manganese nitrate, manganese sulfate, manganese chloride, and manganese chlorate.

8. The preparation method according to any one of claims 1-7, characterized in that, The dispersant includes at least one of polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and the mass ratio of the dispersant to the titanium source is (0.2-3):100; The binder includes at least one of carboxymethyl cellulose and hydroxypropyl cellulose, and the mass ratio of the binder to the titanium source is (1-10):

100. The pore-forming agent includes at least one of polyethylene oxide, polymethyl methacrylate, and guar gum powder; the mass ratio of the pore-forming agent to the titanium source is (0.2~2):

100.

9. A corrugated plate type denitrification catalyst, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

10. A method for flue gas denitrification, characterized in that, The corrugated plate denitrification catalyst according to claim 9 is used to denitrify the flue gas, wherein the flue gas contains carbon monoxide and nitrogen oxides.