CN111111753B - A kind of carbon fiber modified denitration catalyst and preparation method thereof - Google Patents

Abstract

The invention discloses a carbon fiber modified denitration catalyst, relates to the technical field of catalyst preparation, and is mainly made of the following raw materials in parts by weight: 60-80 parts of attapulgite, 20-40 parts of ZSM-5, and 1-2 parts of hardwood pulp 2-4 parts of Rp-chop, 5-20 parts of carbon fiber, 1-3 parts of silicon dioxide, 5-10 parts of manganese oxalate, 1-3 parts of ammonium heptamolybdate, 4-6 parts of cerium nitrate hexahydrate, amino fiber 1-2 parts of vegetable matter, 2-4 parts of polyethylene oxide, 3-6 parts of lactic acid, 1-2 parts of stearic acid, 15-25 parts of ammonia water, 60-80 parts of deionized water. The present invention also provides a preparation method of the above-mentioned denitration catalyst. The beneficial effects of the present invention are: the carbon fiber modified denitration catalyst of the present invention can achieve a denitration rate of 96.2% at 160°C, has a corrosion-resistant skeleton structure and a high specific surface (≥80m ² /g) with excellent low-temperature activity.

Description

A kind of carbon fiber modified denitration catalyst and preparation method thereof

technical field

The invention relates to the technical field of catalyst preparation, in particular to a carbon fiber modified denitration catalyst and a preparation method thereof.

Background technique

Selective catalytic reduction denitrification (SCR) is currently the mainstream dry denitrification technology for removing nitrogen oxides from stationary source flue gas, and is widely used. It uses ammonia as a reducing agent to make NO and NO ₂ in the flue gas pass through the catalyst layer and then reduce to N ₂ and H ₂ O to achieve the purpose of removing NO _x in the flue gas. Most commercial low-temperature catalysts use porous homogeneous catalysts with V ₂ O ₅ , MnO ₂ , MoO ₃ , and TiO ₂ as active components. They have many advantages such as high denitrification rate, good selectivity, and stable operation. favored by researchers. The core issues are carrier optimization, formula development, process application and industrial promotion of denitrification catalysts.

Patent CN201010154269.7 discloses a denitrification catalyst, which is composed of the following components in parts by weight: 70-90 parts of titanium dioxide, 8-16 parts of tungsten trioxide, 1.5-3 parts of vanadium pentoxide, 2-3 parts of aramid 6 parts, 2 to 6 parts of pulp cotton. The denitrification catalyst of the present invention has the advantages of high strength, not easily pulverized, long service life, ideal porosity, high catalytic efficiency, less catalyst consumption and low cost.

The use of pore-forming agent, carrier selection and calcination temperature of honeycomb denitration catalyst directly affects its mechanical strength and porosity, so the selection of raw materials and molding process need to be optimized. At present, daily-use glass and waste incineration mainly use low-sulfur and low-dust layouts. The corrosive components of the flue gas mainly include SO ₂ , HCl, NO ₂ and salt mist, etc., and some flue gas even contains hydrofluoric acid and hydrogen sulfide. In the presence of strong corrosive gases, there is strong acid-base corrosion, and low-temperature flue gas can also produce water vapor condensation corrosion, and the strength decay accelerates corrosion. The mechanical life of conventional commercial vanadium-titanium catalysts can only meet 2-4 months in this working condition.

Contents of the invention

One of the technical problems to be solved by the present invention is to provide a carbon fiber modified denitration catalyst capable of removing _NOx in flue gas under highly corrosive conditions.

The present invention realizes solving above-mentioned technical problem by following technical means:

A carbon fiber modified denitration catalyst, mainly made of the following raw materials in parts by weight: 60-80 parts of attapulgite, 20-40 parts of ZSM-5, 1-2 parts of hardwood pulp, and 2-4 parts of Rp-chop , 5-20 parts of carbon fiber, 1-3 parts of silicon dioxide, 5-10 parts of manganese oxalate, 1-3 parts of ammonium heptamolybdate, 4-6 parts of cerium nitrate hexahydrate, 1-2 parts of amino cellulose, polyethylene oxide 2-4 parts, 3-6 parts of lactic acid, 1-2 parts of stearic acid, 15-25 parts of ammonia water, 60-80 parts of deionized water.

Beneficial effects: the present invention uses attapulgite and ZSM-5 with high specific surface area as carrier, hardwood pulp and Rp-chop as composite pore-forming agent, carbon fiber as structural aid, and manganese dioxide and cerium dioxide as active components , molybdenum trioxide is the cocatalyst;

The special skeleton structure provided by carbon fiber modification not only improves the porosity and specific surface area of the catalyst, but also makes the catalyst have high corrosion resistance and mechanical strength, so that the catalyst can be used in daily-use glass, garbage incineration and other high-corrosion flue gas Medium and long-term stable operation, excellent low-temperature denitrification performance;

Attapulgite and ZSM-5 are used as the catalyst carrier, which has a large specific surface area, special pore structure, enhanced adsorption, desorption catalytic performance, good molding properties and thermal stability, and still has a large specificity after molding and calcination. The surface (≥80m ² /g), after supporting the catalyst active material, makes the catalyst have good low-temperature reactivity and sulfur and water resistance.

Preferably, the carbon fiber has a diameter of 10-20 μm and a length of 1-3 mm.

Beneficial effects: to meet the requirement of extrusion, and form the state of mud-wrapped silk by spinning.

Preferably, the ZSM-5 has a particle size of 5-10 μm and a specific surface of 320-360 m ² /m ³ .

Beneficial effects: The increase in the specific surface can promote the activity of the catalyst, and if it is too high, it will lead to the increase of microscopic internal defects and the intensity attenuation will be aggravated.

Preferably, the preparation method of the carbon fiber modified denitration catalyst comprises the following steps:

(1) adding manganese oxalate, ammonium heptamolybdate, and cerium nitrate hexahydrate to deionized water in the above parts by weight, heating and dissolving to obtain a mixed solution;

(2) Add the attapulgite, ZSM-5, silicon dioxide, carbon fiber, stearic acid, hardwood pulp and Rp-chop of the above-mentioned parts by weight to the mixed solution in step (1) under stirring, after mixing , add aminocellulose, polyethylene oxide and lactic acid at a certain temperature, knead again to obtain mixed mud, and age;

(3) extruding the aged mixed sludge in step (2), drying and calcining.

Preferably, the heating temperature in the step (1) is 70-90°C.

Preferably, the temperature for adding aminocellulose, polyethylene oxide and lactic acid in the step (2) is 50-60° C., and the aging time is 12-48 hours.

Preferably, the calcination temperature in (3) is 700-720° C., and the calcination time is 24 hours.

The second technical problem to be solved by the present invention is to provide a preparation method of a carbon fiber modified denitration catalyst capable of removing _NOx in flue gas under highly corrosive conditions.

The present invention realizes solving above-mentioned technical problem by following technical means:

A method for preparing a carbon fiber modified denitration catalyst, comprising the following steps:

(1) adding manganese oxalate, ammonium heptamolybdate, and cerium nitrate hexahydrate to deionized water in the above parts by weight, heating and dissolving to obtain a mixed solution;

(2) Add the attapulgite, ZSM-5, silicon dioxide, carbon fiber, stearic acid, hardwood pulp and Rp-chop of the above-mentioned parts by weight to the mixed solution in step (1) under stirring, after mixing , add aminocellulose, polyethylene oxide and lactic acid at a certain temperature, knead again to obtain mixed mud, and age;

(3) extruding the aged mixed sludge in step (2), drying and calcining.

Beneficial effects: through kneading, extruding and drying, a homogeneous green body is obtained, and after high-temperature aerobic calcination, a finished denitrification catalyst with a high specific surface area (≥80m ² /g) having a corrosion-resistant skeleton structure and excellent low-temperature activity is obtained.

The carbon fiber modified denitration catalyst of the present invention can achieve a denitration rate of 96.2% at 160°C. Under the premise of a specific surface of 80m ² /g, the axial/radial compressive strength is 7.8Mpa/2.3Mpa, and the corrosion resistance is better than that of The vanadium-titanium base is more than 6 times, and the wear resistance is more than 2 times better than the vanadium-titanium base.

Preferably, the heating temperature in the step (1) is 70-90°C.

Preferably, the temperature for adding aminocellulose, polyethylene oxide and lactic acid in the step (2) is 50-60° C., and the aging time is 12-48 hours.

Preferably, the calcination temperature in (3) is 700-720° C., and the calcination time is 24 hours.

The advantages of the present invention are:

(1) In the present invention, attapulgite and ZSM-5 with high specific surface area are used as carriers, hardwood pulp and Rp-chop are used as composite pore-forming agents, carbon fibers are used as structural aids, and manganese dioxide and ceria are used as active components , molybdenum trioxide is the cocatalyst;

The special skeleton structure provided by carbon fiber modification not only improves the porosity and specific surface area of the catalyst, but also makes the catalyst have high corrosion resistance and mechanical strength, so that the catalyst can be used in daily-use glass, garbage incineration and other high-corrosion flue gas Medium and long-term stable operation, excellent low-temperature denitrification performance;

Attapulgite and ZSM-5 are used as the catalyst carrier, which has a large specific surface area, special pore structure, enhanced adsorption, desorption catalytic performance, good molding properties and thermal stability, and still has a large specificity after molding and calcination. The surface area (≥80m ² /g), after loading the catalyst active material, makes the catalyst have good low-temperature reactivity and sulfur and water resistance;

(2) The carbon fiber modified denitration catalyst of the present invention can achieve a denitration rate of 96.2% at 160°C. Under the premise of a specific surface area of 80m ² /g, the axial/radial compressive strength is 7.8Mpa/2.3Mpa, and the corrosion resistance The comparison is more than 6 times better than that of titanium-based catalysts, and the comparison of wear resistance is more than 2 times better than that of titanium-based catalysts.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments 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. Obviously, the described embodiments are part of the present invention Examples, not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The test materials and reagents used in the following examples can be obtained from commercial sources unless otherwise specified.

Those that do not indicate specific techniques or conditions in the examples can be carried out according to the techniques or conditions described in the documents in this field or according to the product instructions.

Polyethylene oxide was purchased from Shanghai Liansheng Chemical Co., Ltd.: 0.5% aqueous solution viscosity mpa s: 350±55;

Amino cellulose was purchased from Shaoxing Hualong Environmental Protection Materials Co., Ltd. (index: viscosity mpa s155, 0.1wt% aqueous solution, molecular weight: ~150000)

ZSM-5 was purchased from Dalian Xintao Chemical;

Hardwood pulp was purchased from Shandong Daoxin New Material Co., Ltd.;

Rp-chop was purchased from Jiangsu Kangdafu New Material Technology Co., Ltd.;

Ammonium heptamolybdate was purchased from Hefei Jinxin Oleochemical Co., Ltd.

Example 1

The preparation method of carbon fiber modified denitration catalyst comprises the following steps:

(1) Add 0.5kg of manganese oxalate, 0.1kg of ammonium heptamolybdate, and 0.5kg of cerium nitrate hexahydrate into a mixed solution of 6kg of deionized water, and heat to 70°C to fully dissolve to obtain a mixed solution;

(2) Add 7kg of attapulgite, 3kg of ZSM-5 (specific surface 340m ² /g), 0.1kg of silicon dioxide, 0.5kg of carbon fiber, 0.1 In the mixture of kg stearic acid, 0.1kg hardwood pulp and 0.2kgRp-chop, after high-speed mixing (750rpm) is uniform, add 0.1kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) The catalyst obtained in the step (3) is calcined at a maximum temperature of 700° C. for 24 hours to complete the processes of organic matter decomposition, pore formation, substrate sintering and active material conversion, and a carbon fiber modified denitration catalyst is obtained.

Example 2

The preparation method of carbon fiber modified denitration catalyst comprises the following steps:

(1) Add 1 kg of manganese oxalate, 0.3 kg of ammonium heptamolybdate, and 0.6 kg of cerium nitrate hexahydrate into a mixed solution of 10 kg of deionized water, and heat to 80° C. to fully dissolve to obtain a mixed solution;

(2) Add 6kg attapulgite, 4kg ZSM-5 (specific surface 340m ² /g), 0.1kg silicon dioxide, 1.2kg carbon fiber, 0.15 In the mixture of kg stearic acid, 0.1kg hardwood pulp and 0.4kgRp-chop, after high-speed mixing (750rpm) is uniform, add 0.15kg aminocellulose, 0.2kg polyethylene oxide and 0.5kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 710° C. for 24 hours to complete the processes of organic matter decomposition, pore formation, substrate sintering, and active material conversion, to obtain a carbon fiber modified denitration catalyst.

Example 3

The preparation method of carbon fiber modified denitration catalyst comprises the following steps:

(1) Add 0.8 kg of manganese oxalate, 0.25 kg of ammonium heptamolybdate, and 0.6 kg of cerium nitrate hexahydrate into a mixed solution of 8 kg of deionized water, and heat to 90° C. to fully dissolve to obtain a mixed solution;

(2) Add 8kg attapulgite, 2kg ZSM-5 (specific surface 340m ² /g), 0.3kg silicon dioxide, 2kg carbon fiber, 0.2kg In the mixture of stearic acid, 0.15kg hardwood pulp and 0.3kg Rp-chop, after high-speed mixing (750rpm) is uniform, add 0.2kg aminocellulose, 0.4kg polyethylene oxide and 0.6kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) The catalyst obtained in the step (3) is calcined at a maximum temperature of 720° C. for 24 hours to complete the process of organic matter decomposition and pore formation, substrate sintering and active material conversion to obtain a carbon fiber modified denitration catalyst.

Comparative example 1

(1) Add 1 kg of manganese oxalate, 0.3 kg of ammonium heptamolybdate, and 0.6 kg of cerium nitrate hexahydrate into a mixed solution of 10 kg of deionized water, and heat to 80° C. to fully dissolve to obtain a mixed solution;

(2) Add 6kg attapulgite, 3kg ZSM-5 (specific surface 340m ² /g), 0.1kg silicon dioxide, 1.2kg carbon fiber, 0.15 In the mixture of kg stearic acid, 0.1kg hardwood pulp and 0.4kgRp-chop, after high-speed mixing (750rpm) is uniform, add 0.15kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 710° C. for 24 hours to obtain the target product.

Comparative example 2

(1) Add 0.5 kg of manganese oxalate, 0.1 kg of ammonium heptamolybdate, and 0.6 kg of cerium nitrate hexahydrate into a mixed solution of 10 kg of deionized water, and heat to 80° C. to fully dissolve to obtain a mixed solution;

(2) With the mixed solution in step (1) under low-speed stirring (50rpm), add 10kg titanium dioxide, 0.1kg silicon dioxide, 1.2kg carbon fiber, 0.15kg stearic acid, 0.1kg hardwood pulp and 0.4kg Rp In the mixture of -chop, after high-speed mixing (750rpm) is uniform, add 0.15kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg lactic acid at a temperature of 60°C, and then high-speed mixing (750rpm) for 3 hours to obtain a mixture Mud, aging for 24h;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 650° C. for 24 hours to obtain the target product.

Comparative example 3

(1) Add 1 kg of manganese oxalate, 0.3 kg of ammonium heptamolybdate, and 0.6 kg of cerium nitrate hexahydrate into a mixed solution of 10 kg of deionized water, and heat to 80°C to fully dissolve to obtain a mixed solution;

(2) With the mixed solution in step (1) under low-speed stirring (50rpm), add 10kg titanium dioxide, 0.1kg silicon dioxide, 1.2kg glass fiber, 0.15kg stearic acid, 0.1kg hardwood pulp and 0.4kg In the mixture of Rp-chop, after high-speed mixing (750rpm) is uniform, add 0.15kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg lactic acid at a temperature of 60°C, and then high-speed mixing (750rpm) for 3 hours to obtain Mix the mud and carry out aging for 24h;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 650° C. for 24 hours to obtain the target product.

Comparative example 4

(1) Add 0.5 kg of manganese oxalate, 0.1 kg of ammonium heptamolybdate, and 0.5 kg of cerium nitrate hexahydrate into a mixed solution of 6 kg of deionized water, and heat to 80° C. to fully dissolve to obtain a mixed solution;

(2) Add 7kg of attapulgite, 3kg of ZSM-5 (specific surface 240m ² /g), 0.1kg of silicon dioxide, 0.5kg of carbon fiber, 0.1 In the mixture of kg stearic acid, 0.1kg hardwood pulp and 0.2kgRp-chop, after high-speed mixing (750rpm) is uniform, add 0.1kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 700° C. for 24 hours to obtain the target product.

Comparative example 5

(1) Add 0.5 kg of manganese oxalate, 0.1 kg of ammonium heptamolybdate, and 0.5 kg of cerium nitrate hexahydrate into a mixed solution of 6 kg of deionized water, and heat to 80° C. to fully dissolve to obtain a mixed solution;

(2) Add 7kg of attapulgite, 3kg of ZSM-5 (specific surface 400m ² /g), 0.1kg of silicon dioxide, 0.5kg of carbon fiber, 0.1 In the mixture of kg stearic acid, 0.1kg hardwood pulp and 0.2kgRp-chop, after high-speed mixing (750rpm) is uniform, add 0.1kg aminocellulose, 0.2kg polyethylene oxide and 0.3kg Lactic acid, high-speed mixing (750rpm) for 3 hours again, to obtain mixed mud, aging for 24 hours;

(3) Extrude the mixed catalyst sludge obtained in the step (2), the number of pores of the extruded honeycomb catalyst is 30×30, microwave drying to a weight loss of ≤0.01kg per hour, and complete the drying and dehydration process.

(4) Calcining the catalyst obtained in the step (3) at a maximum temperature of 700° C. for 24 hours to obtain the target product.

Example 4

The catalyst monomer measured in embodiment 1, embodiment 2, embodiment 3, comparative example 1, comparative example 2, comparative example 3, comparative example 4 and comparative example 5 is cut into the test block of 150mm * 150mm * 150mm, Use the electronic universal testing machine to test the mechanical strength, use the static nitrogen adsorption method to test its specific surface area, and use the wear resistance tester to test the weight loss rate of the catalyst when it is washed for 2 hours at a wind speed of 14.5m/s;

Corrosion resistance test is carried out by controlling scalar routine activity detection and gas distribution in flue gas for 24 hours to measure corrosion weight loss: the experiment is carried out at 160°C, the total gas flow rate is 500mL/min, the reaction gas composition is 300-500ppm nitric oxide, 10-30ppm HF standard gas, 20-35ppm sulfur dioxide, 300-500ppm ammonia, 8-10wt% oxygen, 8-12wt% water, and the rest being nitrogen.

Denitrification rate measurement method:

1) Take a unit with a size of 10mm×10mm×30mm and no obvious physical damage as the sample to be tested. After wrapping the two ends of the catalyst sample with high-temperature resistant ceramic fiber cotton, put it into the reactor, and wrap the gap between the two ends of the catalyst with ceramic fiber Cotton sealed tightly, ready to use. Slowly introduce air into the system, and keep it for 10 minutes under the condition that the pressure is not lower than 0.1MPa, then check all sealing points by brushing neutral foaming agent, etc., and deal with any leakage. After passing the leak test, open the exhaust to reduce the system to normal pressure.

2) Without feeding NH3, HF and NO, adjust the flue gas conditions to meet the above flue gas ratio requirements, and keep it for 30 hours. However, every 1h, measure the volume fraction of SO ₂ and SO ₃ in the flue gas at the inlet and outlet of the reactor. When the same trend does not exist in the data of 4 consecutive tests and the relative deviation is <10%, the aging ends.

3) According to the experimental requirements of the above-mentioned flue gas ratio in the table, all the gas is introduced, and it is stable and kept for 1 hour. Then measure the volume fraction of NOx at the inlet and outlet every 1h. When the same trend does not exist in the 4 consecutive measurement results and the relative deviation of the measurement results is not greater than 3%, the test is stable, and the total test time is 24h.

Table 1 is the measurement result

It can be seen from Table 1 that in the examples, the carbon fiber modified denitration catalyst has high denitration efficiency, the shaft/diameter pressure resistance is more than twice that of the conventional titanium substrate-based denitration catalyst, and its corrosion resistance is better than that of the conventional titanium substrate-based denitrification catalyst. Catalyst 6 times more. Comparative Example 1 verified that the ratio of active substances changed, which had a great impact on the denitrification activity of the catalyst; in Comparative Examples 2 and 3, titanium dioxide was used to prepare the denitrification catalyst, and the specific surface area of the prepared catalyst was less than 80m ² /g. Compared with attapulgite, ZSM-5 base material, and carbon fiber modified molding, it still has a larger specific surface (≥80m ² /g) after calcining. After the catalyst prepared in the embodiment supports the catalyst active material, the catalyst It has good low-temperature reactivity and sulfur and water resistance, which improves the service life of the catalyst in extremely acidic low-temperature flue gas; Comparative Examples 4 and 5 verify the necessity of using ZSM-5 (320-360m ² /g). The surface elevation can promote the activity of the catalyst, and if it is too high, it will lead to the increase of microscopic internal defects and the intensity attenuation will be aggravated.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be described in the foregoing embodiments Modifications are made to the recorded technical solutions, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A carbon fiber modified denitration catalyst, characterized in that it is mainly made of the following raw materials in parts by weight: 60-80 parts of attapulgite, 20-40 parts of ZSM-5, 1-2 parts of hardwood pulp, Rp - 2-4 parts of chop, 5-20 parts of carbon fiber, 1-3 parts of silicon dioxide, 5-10 parts of manganese oxalate, 1-3 parts of ammonium heptamolybdate, 4-6 parts of cerium nitrate hexahydrate, 1-2 parts of amino cellulose 2 to 4 parts of polyethylene oxide, 3 to 6 parts of lactic acid, 1 to 2 parts of stearic acid, 15 to 25 parts of ammonia water, 60 to 80 parts of deionized water; the specific surface of ZSM-5 is 320 to 360 m ² /g. 2. The carbon fiber modified denitration catalyst according to claim 1, characterized in that the carbon fiber has a diameter of 10-20 μm and a length of 1-3 mm. 3. The carbon fiber modified denitration catalyst according to claim 1, characterized in that the ZSM-5 has a particle size of 5-10 μm. 4. carbon fiber modified denitration catalyst according to claim 1, is characterized in that, the preparation method of described carbon fiber modified denitration catalyst comprises the following steps: (1) adding manganese oxalate, ammonium heptamolybdate, and cerium nitrate hexahydrate to deionized water in the above parts by weight, heating and dissolving to obtain a mixed solution; (2) Add the attapulgite, ZSM-5, silicon dioxide, carbon fiber, stearic acid, hardwood pulp and Rp-chop of the above-mentioned parts by weight to the mixed solution in step (1) under stirring, after mixing , add aminocellulose, polyethylene oxide and lactic acid at a certain temperature, knead again to obtain mixed mud, and age; (3) extruding the aged mixed sludge in step (2), drying and calcining. 5. The carbon fiber modified denitration catalyst according to claim 4, characterized in that, the heating temperature in the step (1) is 80°C. 6. The carbon fiber modified denitration catalyst according to claim 4, characterized in that the temperature of adding aminocellulose, polyethylene oxide and lactic acid in the step (2) is 50-60°C, and the aging time is 12-48h . 7. The carbon fiber modified denitration catalyst according to claim 4, characterized in that the calcination temperature in (3) is 700-720° C., and the calcination time is 24 hours. 8. prepare the preparation method of carbon fiber modified denitration catalyst as claimed in claim 1, it is characterized in that, comprise the following steps: (1) adding manganese oxalate, ammonium heptamolybdate, and cerium nitrate hexahydrate to deionized water in the above parts by weight, heating and dissolving to obtain a mixed solution; (2) Add the attapulgite, ZSM-5, silicon dioxide, carbon fiber, stearic acid, hardwood pulp and Rp-chop of the above-mentioned parts by weight to the mixed solution in step (1) under stirring, after mixing , add aminocellulose, polyethylene oxide and lactic acid at a certain temperature, knead again to obtain mixed mud, and age; (3) extruding the aged mixed sludge in step (2), drying and calcining. 9. The method for preparing a carbon fiber modified denitration catalyst according to claim 8, characterized in that, the heating temperature in the step (1) is 80°C. 10. The preparation method of carbon fiber modified denitration catalyst according to claim 8, characterized in that, the temperature of adding aminocellulose, polyethylene oxide and lactic acid in the step (2) is 50-60°C, and the aging time is 12～48h.