CN103933971A - Low-temperature denitration catalyst as well as preparation method and application thereof - Google Patents

Abstract

The invention relates to a low-temperature denitration catalyst and its preparation method and application. The low-temperature denitration catalyst uses cordierite honeycomb ceramics as the first carrier, active titanium dioxide as the second carrier, and supports the active component manganese oxide and auxiliary agent cerium oxide. The weight percent composition of the catalyst is: _TiO2 is 1.7-15.0% of the cordierite honeycomb ceramic carrier, manganese cerium oxide is 0.64-2.00% of the cordierite honeycomb ceramic carrier, and the mass ratio of cerium oxide: manganese oxide = 0-2.1: 1. The invention has the advantages of simple preparation process, low cost, high activity at low temperature and large-scale industrialization.

Description

A kind of low temperature denitrification catalyst and its preparation method and application

Field

The invention relates to a catalyst for removing flue gas _NOx at low temperature, a preparation method and application.

Background technique

Nitrogen oxides (NO _x ) cause acid rain and photochemical smog, and contribute significantly to PM2.5, which is one of the main air pollutants. In particular, nitrogen oxides (NO _x ) emitted from stationary sources account for more than 60%, so they must be controlled before they are emitted. At present, ammonia selective catalytic reduction technology (NH ₃ -SCR) is considered to be one of the most effective technologies. The SCR catalyst for industrial application is mainly V ₂ O ₅ -WO ₃ /TiO ₂ catalyst, which has high denitrification activity, But the reaction temperature must be operated between 330 and 400°C. For this reason, it is generally necessary to install the SCR device after the boiler economizer and before the air preheater. At this time, since the flue gas has not been dedusted, it is inevitable that soot and other impurities will block the catalyst pores and affect the active components. poisoning and shorten catalyst life. In addition, most existing boiler economizers, air preheaters and boilers in China are assembled as one, and the high-temperature characteristics of this technology make it difficult to match existing boilers. In order to avoid the catalyst being blocked and poisoned by _SO2 and dust, the SCR reactor should be placed after the dust collector and desulfurizer (flue gas temperature is usually below 150°C). Therefore, there is an urgent need to develop low-temperature and high-activity SCR catalysts.

In recent years, MnO _x has attracted extensive attention due to its excellent low-temperature activity. etc. (J.Phys.Chem.B,2004,108,9927-9936; J.Catal.,2004,221,421-431) (American Journal of Physical Chemistry, Series B, 2004,108,9927-9936; Journal of Catalysis, 2004 , 221,421-431) studies have shown that at a low temperature of 120 ° C, the order of catalytic activity of metal oxides is Mn>Cu≥Cr≥Co>Fe≥V>>Ni. Smirniotis et al. (Angew.Chem.Int.Edit., 2001, 40, 2479-2482) (German Applied Chemistry (International Edition), 2001, 40, 2479-2482)) comparatively studied the 4th cycle transition metal oxidation of TiO ₂ loading According to the influence of substances on the performance of NH ₃ -SCR reaction, it was found that MnO _x /TiO ₂ catalyst showed the highest catalytic activity no matter at 100℃ or 120℃.

_CeO2 has been extensively studied due to its good oxygen storage performance and redox performance. The most important property of CeO ₂ is as an oxygen storage source. It achieves the purpose of storing and releasing oxygen through the change of oxidation state Ce ³⁺ and Ce ⁴⁺ under oxidation and reduction conditions. The MnO _x -CeO ₂ catalyst studied by Qi et al. (J.Catal., 2003, 217, 434-441 (Journal of Catalysis, 2003, 217, 434-441)) has a NO conversion rate close to 100% at 120°C. Wu et al. (J.Hazard.Mater., 2007,145,488-494 (Journal of Hazardous Substances, 2007,145,488-494)) prepared by sol-gel method MnO _x /TiO ₂ catalyst, also obtained better low temperature effect, After further adding Ce, the denitration activity of the catalyst was significantly improved (Catal. Commun., 2008, 9, 2217-2220 (Catalytic Communications, 2008, 9, 2217-2220)). Since most of the catalysts studied at present are mainly powder or particles, although they show good catalytic activity under experimental conditions, the industrial application of this catalyst is limited due to factors such as large bed pressure drop.

Contents of the invention

The purpose of the present invention is to provide a flue gas denitrification catalyst with simple preparation process, low cost, low temperature and high activity, and large-scale industrialization, as well as its preparation method and application.

Cordierite honeycomb ceramics have the characteristics of high strength, small pressure drop, good thermal stability and low cost, and are widely used in chemical and environmental protection fields such as catalytic conversion, but their specific ^surface The active component can be fully dispersed on it, and the carrier component must be coated on the surface of the cordierite. Anatase _TiO2 has a large specific surface area, and the stability of sulfate and other substances on its surface is much lower than that of other metal oxides, which can protect the loaded active components, so _TiO2 is selected as the carrier group of SCR catalysts point.

In view of the above problems and analysis, the present invention prepares TiO ₂ by sol-gel method, and loads it on the treated honeycomb cordierite, and then loads active component Mn and auxiliary agent Ce by co-impregnation method to obtain monolithic catalyst.

The catalyst used for low-temperature flue gas denitrification in the present invention uses cordierite honeycomb ceramics as the first carrier, active titanium dioxide as the second carrier, and supports the active component manganese oxide and auxiliary agent cerium oxide. The weight percentage of the catalyst is composed of: TiO ₂ is 1.7-15.0% of the cordierite honeycomb ceramic carrier, and 0.64-2.00% of the manganese-cerium oxide as the cordierite honeycomb ceramic carrier, wherein the mass ratio of cerium oxide:manganese oxide=(0-2.1):1.

The preparation method of the present invention comprises the steps:

(1) Cordierite carrier pretreatment:

Put the cut cordierite into 25wt% ammonia water, soak at room temperature for 1-6 hours, wash with water until neutral, place at room temperature for 2-4 hours, dry at 110-150°C for 6-12 hours, and roast at 400-600°C for 3-6 hours;

(2) Preparation of _TiO2 coating:

Mix butyl titanate and ethanol uniformly under rapid stirring for 1-3 hours, then slowly add to the mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been mixed uniformly, continue stirring for 1-3 hours, and then stand at room temperature for 4-8 hours , to obtain a sol, wherein the volume ratio of the above-mentioned substances is butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid=1: (3.2-6.5): (0.1-0.2): (0.1-0.7): (0.05-0.2 ), the first ethanol consumption and the second ethanol consumption are 1/2 of the total amount of ethanol;

Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, make the sol at least completely submerge the carrier, take it out after 10-40min, blow off the sol remaining in the cordierite channels, and place it at room temperature for 0.5-2h, 100- Dry at 120°C for 8-24h, and bake at 350-450°C for 4-8h to obtain a carrier loaded with _TiO2 coating;

(3) preparation catalyst:

According to cerium oxide: manganese oxide mass ratio = (0-2.1): 1, cerium nitrate and manganese acetate are prepared into aqueous solution, wherein manganese acetate: water = 1g: 12-16ml; will be loaded with _TiO The carrier of coating is impregnated in Take it out after 10-40min in the aqueous solution containing cerium nitrate and manganese acetate, blow off the liquid remaining in the cordierite channel, place it at room temperature for 0.5-2h, dry it at 100-120°C for 8-24h, and roast it at 300-400°C for 3- 6h, the catalyst was obtained.

The prepared catalyst of the present invention carries out the flue gas denitrification reaction under the following conditions:

A fixed bed reactor is used, the reaction temperature is controlled at 80-145°C, the reaction pressure is normal pressure, and the reaction volume space velocity is controlled at 1000h ^-1 -18000h ^-1 .

The present invention has the following advantages:

1. TiO ₂ , active components and additives are firmly bonded to cordierite and are not easy to peel off.

2. The denitrification activity of the catalyst is better, especially at low temperature.

3. The preparation process is relatively simple.

4. The preparation cost is relatively low.

Detailed ways

Example 1

Put the cut cordierite into 25wt% ammonia water, soak it at room temperature for 1 hour, wash it with water until neutral, place it at room temperature for 2 hours, dry it at 110°C for 6 hours, roast it at 400°C for 3 hours, and weigh it for later use after cooling. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 1 hour, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been mixed uniformly, continue stirring for 1 hour, and then stand at room temperature for 4 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 3.2: 0.1: 0.1: 0.05, the amount of ethanol used for the first time and the amount of ethanol used for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 10 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 1 hour, dry it at 100°C for 8 hours, bake it at 450°C for 4 hours, and weigh it , TiO ₂ loading amount (relative to the initial mass of the cordierite honeycomb ceramic carrier) was 1.73%. Immerse the coated cordierite carrier in 70ml of aqueous solution containing 5.8824g of manganese acetate, take it out after 10min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 0.5h, dry at 100°C for 12h, and then dry it at 300°C After firing for 6 hours, the active component manganese oxide content was 0.64% (relative to the initial mass of the cordierite honeycomb ceramic carrier), and the _TiO content (relative to the initial mass of the cordierite honeycomb ceramic carrier) was 1.73%. catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 80°C and the space velocity is 1000h ^-1 , the conversion rate of NO is 82%.

Example 2

Put the cut cordierite into 25wt% ammonia water, soak at room temperature for 2 hours, wash with water until neutral, place at room temperature for 3 hours, dry at 120°C for 8 hours, roast at 500°C for 4 hours, and weigh after cooling for later use. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 2 hours, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been uniformly mixed, continue to stir for 2 hours, and then stand at room temperature for 6 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 4: 0.15: 0.2: 0.1, the amount of ethanol for the first time and the amount of ethanol for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 20 minutes, blow off the sol remaining in the cordierite channels, place it at room temperature for 1 hour, dry it at 110°C for 8 hours, bake it at 450°C for 6 hours, and weigh it , TiO ₂ loading amount (relative to the initial mass of the cordierite honeycomb ceramic carrier) was 2.08%. Immerse the coated cordierite carrier in 75ml aqueous solution containing 5.8824g manganese acetate and 0.5211g cerium nitrate, take it out after 20min, blow off the liquid remaining in the cordierite channel, place it at room temperature for 1h, and dry it at 110°C 12h, after 350 ℃ of roasting 5h, the obtained manganese oxide content is 0.65%, and cerium oxide content is 0.17% (relative to the initial mass of cordierite honeycomb ceramic carrier), TiO ₂ content (relative to cordierite honeycomb ceramic carrier Initial mass) of 2.02% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 100°C and the space velocity is 3000h ^-1 , the conversion rate of NO is 87%.

Example 3

Put the cut cordierite into 25wt% ammonia water, soak it at room temperature for 3 hours, wash it with water until neutral, place it at room temperature for 4 hours, dry it at 130°C for 10 hours, roast it at 600°C for 5 hours, and weigh it for later use after cooling. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 3 hours, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been uniformly mixed, continue stirring for 3 hours, and then stand at room temperature for 8 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 5: 0.2: 0.3: 0.2, the amount of ethanol for the first time and the amount of ethanol for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 30 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 1.5 hours, dry at 120°C for 8 hours, and bake at 450°C for 8 hours. Repeat the above steps, weigh after coating twice, and the TiO ₂ loading amount (relative to the initial mass of the cordierite honeycomb ceramic carrier) is 4.13%. Immerse the coated cordierite carrier in 80ml aqueous solution containing 5.8824g manganese acetate and 1.0422g cerium nitrate, take it out after 30min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 2h, and dry it at 120°C 15h, after 400 ℃ of roasting 4h, the obtained manganese oxide content is 0.61%, and cerium oxide content is 0.29% (relative to the initial mass of cordierite honeycomb ceramic carrier), TiO ₂ content (relative to cordierite honeycomb ceramic carrier initial mass) of 4.13% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 120°C and the space velocity is 6000h ^-1 , the conversion rate of NO is 94%.

Example 4

The cut cordierite was put into 25wt% ammonia water, soaked at room temperature for 4 hours, washed with water until neutral, left at room temperature for 2 hours, dried at 140°C for 6 hours, roasted at 400°C for 6 hours, and weighed after cooling for later use. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 1 hour, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been uniformly mixed, continue to stir for 2 hours, and then stand at room temperature for 4 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 5: 0.1: 0.4: 0.05, the amount of ethanol for the first time and the amount of ethanol for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 40 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 2 hours, dry it at 110°C for 12 hours, and bake it at 450°C for 4 hours. Repeat the above steps, weigh after coating three times, and the amount of TiO ₂ loaded (relative to the initial mass of the cordierite honeycomb ceramic carrier) is 6.02%. Immerse the coated cordierite carrier in 85ml aqueous solution containing 5.8824g manganese acetate and 1.5633g cerium nitrate, take it out after 40min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 2h, and dry it at 110°C 12h, after 300 ℃ of roasting 6h, the obtained manganese oxide content is 0.59%, and cerium oxide content is 0.44% (relative to the initial mass of cordierite honeycomb ceramic carrier), TiO ₂ content (relative to cordierite honeycomb ceramic carrier Initial mass) of 6.02% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 145°C and the space velocity is 9000h ^-1 , the conversion rate of NO is 95%.

Example 5

The cut cordierite was put into 25wt% ammonia water, soaked at room temperature for 5 hours, washed with water until neutral, left at room temperature for 3 hours, dried at 150°C for 6 hours, calcined at 500°C for 4 hours, weighed after cooling for later use. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 1 hour, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been mixed uniformly, continue to stir for 3 hours, and then stand at room temperature for 6 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 6.5: 0.15: 0.5: 0.05, the amount of ethanol for the first time and the amount of ethanol for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 10 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 0.5h, dry at 110°C for 112h, and bake at 400°C for 6h. Repeat the above steps, weigh after coating four times, and the amount of TiO ₂ loaded (relative to the initial mass of the cordierite honeycomb ceramic carrier) is 8.07%. Immerse the coated cordierite carrier in 90ml of aqueous solution containing 5.8824g of manganese acetate and 2.0844g of cerium nitrate, take it out after 10min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 0.5h, and bake at 110°C After drying for 18 hours and firing at 350°C for 5 hours, the manganese oxide content was 0.60%, the cerium oxide content was 0.49% (relative to the initial mass of the cordierite honeycomb ceramic carrier), and the _TiO2 content (relative to the cordierite honeycomb ceramic carrier initial mass) of 8.07% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 80°C and the space velocity is 12000h ^-1 , the conversion rate of NO is 65%.

Example 6

Put the cut cordierite into 25wt% ammonia water, soak it at room temperature for 6 hours, wash it with water until neutral, place it at room temperature for 4 hours, dry it at 110°C for 12 hours, roast it at 600°C for 3 hours, and weigh it for later use after cooling. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 2 hours, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been uniformly mixed, continue stirring for 3 hours, and then stand at room temperature for 8 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 4.5: 0.2: 0.6: 0.1, the amount of ethanol for the first time and the amount of ethanol for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 20 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 1 hour, dry it at 120°C for 12 hours, and bake it at 450°C for 4 hours. Repeat the above steps, weigh after coating twice, and the TiO ₂ loading amount (relative to the initial mass of the cordierite honeycomb ceramic carrier) is 5.03%. Immerse the coated cordierite carrier in 80ml of aqueous solution containing 5.8824g of manganese acetate and 4.1688g of cerium nitrate, take it out after 20min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 1h, and dry it at 120°C After 10h, 400 ℃ roasting 3h, obtained manganese, oxide content is 0.58%, cerium oxide content is 0.82% (relative to the initial mass of cordierite honeycomb ceramic carrier), TiO ₂ content (relative to cordierite honeycomb ceramic carrier initial mass) of 5.03% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 120°C and the space velocity is 15000h ^-1 , the conversion rate of NO is 78%.

Example 7

The cut cordierite was put into 25wt% ammonia water, soaked at room temperature for 2 hours, washed with water until neutral, left at room temperature for 3 hours, dried at 120°C for 10 hours, roasted at 400°C for 6 hours, and weighed after cooling for later use. Mix a certain amount of butyl titanate and ethanol uniformly under rapid stirring for 3 hours, then slowly add a certain amount of mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been mixed uniformly, continue stirring for 3 hours, and then stand at room temperature for 6 hours. A transparent sol was obtained. Wherein, the volume ratio of the above-mentioned substances is, butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 5.5: 0.1: 0.7: 0.1, the amount of ethanol used for the first time and the amount of ethanol used for the second time are both the total amount of ethanol 1/2. Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, take it out after 30 minutes, blow off the sol remaining in the cordierite channels, leave it at room temperature for 1 hour, dry it at 100°C for 24 hours, and bake it at 400°C for 6 hours. Repeat the above steps, weigh after coating three times, and the amount of TiO ₂ loaded (relative to the initial mass of the cordierite honeycomb ceramic carrier) is 7.19%. Immerse the coated cordierite carrier in 80ml aqueous solution containing 5.8824g manganese acetate and 8.3376g cerium nitrate, take it out after 30min, blow off the liquid remaining in the cordierite channels, place it at room temperature for 1h, and dry it at 110°C 12h, after 400 ℃ of roasting 5h, the obtained manganese oxide content is 0.60%, and cerium oxide content is 1.26% (relative to the initial mass of cordierite honeycomb ceramic carrier), TiO ₂ content (relative to cordierite honeycomb ceramic carrier Initial mass) of 7.19% monolithic catalyst. The simulated flue gas composition is 500ppmNO, 500ppmNH ₃ , 5.0%O ₂ , and N ₂ is the balancer. When the reaction temperature is controlled at 145°C and the space velocity is 18000h ^-1 , the conversion rate of NO is 81%.

Claims (3)

1. A low-temperature denitration catalyst, characterized in that the catalyst uses cordierite honeycomb ceramics as the first carrier, active titanium dioxide as the second carrier, and supports the active component manganese oxide and auxiliary agent cerium oxide. The catalyst weight percentage is composed of: TiO ₂ is 1.7-15.0% of the cordierite honeycomb ceramic carrier, manganese cerium oxide is 0.64-2.00% of the cordierite honeycomb ceramic carrier, and the mass ratio of cerium oxide: manganese oxide is 0-2.1:1. 2. the preparation method of a kind of low-temperature denitration catalyst as claimed in claim 1, is characterized in that comprising the steps: (1) Cordierite carrier pretreatment: Put the cut cordierite into 25wt% ammonia water, soak at room temperature for 1-6 hours, wash with water until neutral, place at room temperature for 2-4 hours, dry at 110-150°C for 6-12 hours, and roast at 400-600°C for 3-6 hours; (2) Preparation of _TiO2 coating: Mix butyl titanate and ethanol uniformly under rapid stirring for 1-3 hours, then slowly add to the mixed solution of ethanol, glacial acetic acid, hydrochloric acid and water that has been mixed uniformly, continue stirring for 1-3 hours, and then stand at room temperature for 4-8 hours , to obtain a sol, wherein, the volume ratio of the above substances is butyl titanate: ethanol: water: glacial acetic acid: hydrochloric acid = 1: 3.2-6.5: 0.1-0.2: 0.1-0.7: 0.05-0.2, the amount of ethanol for the first time and The amount of ethanol for the second time is 1/2 of the total amount of ethanol; Immerse the pretreated cordierite honeycomb ceramic carrier in the prepared sol, make the sol at least completely submerge the carrier, take it out after 10-40min, blow off the sol remaining in the cordierite channels, and place it at room temperature for 0.5-2h, 100- Dry at 120°C for 8-24h, and bake at 350-450°C for 4-8h to obtain a carrier loaded with _TiO2 coating; (3) Preparation of catalyst: According to the mass ratio of cerium oxide: manganese oxide = 0-2.1: 1, prepare cerium nitrate and manganese acetate into an aqueous solution, wherein manganese acetate: water = 1g: 12-16ml; impregnate the carrier loaded with _TiO2 coating in the solution containing nitric acid After 10-40min in the aqueous solution of cerium and manganese acetate, take it out, blow off the liquid remaining in the cordierite channels, place it at room temperature for 0.5-2h, dry it at 100-120°C for 8-24h, and bake it at 300-400°C for 3-6h. That is, a catalyst is obtained. 3. the application of a kind of low-temperature denitration catalyst as claimed in claim 1, is characterized in that comprising the steps: The catalyst is used in a fixed-bed reactor, the reaction temperature is controlled at 80-145°C, the reaction pressure is normal pressure, and the reaction volume space velocity is 1000h ^-1 to 18000h ^-1 .