CN113457717A - Catalyst for low-temperature low-oxygen flue gas denitration, preparation method and application thereof - Google Patents
Catalyst for low-temperature low-oxygen flue gas denitration, preparation method and application thereof Download PDFInfo
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- 239000001301 oxygen Substances 0.000 title claims abstract description 32
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 32
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title description 6
- 239000003546 flue gas Substances 0.000 title description 6
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000004202 carbamide Substances 0.000 claims abstract description 44
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000012494 Quartz wool Substances 0.000 claims abstract description 9
- 229910000616 Ferromanganese Inorganic materials 0.000 claims abstract description 4
- DALUDRGQOYMVLD-UHFFFAOYSA-N iron manganese Chemical compound [Mn].[Fe] DALUDRGQOYMVLD-UHFFFAOYSA-N 0.000 claims abstract description 4
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 claims description 30
- 239000007864 aqueous solution Substances 0.000 claims description 21
- 238000011068 loading method Methods 0.000 claims description 19
- 239000000243 solution Substances 0.000 claims description 19
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical compound [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
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- 239000000203 mixture Substances 0.000 claims description 7
- 239000012018 catalyst precursor Substances 0.000 claims description 6
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 17
- 238000000354 decomposition reaction Methods 0.000 description 15
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 10
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- 229910052742 iron Inorganic materials 0.000 description 7
- 229910052748 manganese Inorganic materials 0.000 description 7
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 238000005303 weighing Methods 0.000 description 6
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 5
- 229910021529 ammonia Inorganic materials 0.000 description 5
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- 231100001261 hazardous Toxicity 0.000 description 1
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- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/03—Catalysts comprising molecular sieves not having base-exchange properties
- B01J29/0308—Mesoporous materials not having base exchange properties, e.g. Si-MCM-41
- B01J29/0341—Mesoporous materials not having base exchange properties, e.g. Si-MCM-41 containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
- B01D53/8628—Processes characterised by a specific catalyst
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8678—Removing components of undefined structure
- B01D53/8687—Organic components
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/20—Reductants
- B01D2251/206—Ammonium compounds
- B01D2251/2067—Urea
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2257/00—Components to be removed
- B01D2257/40—Nitrogen compounds
- B01D2257/404—Nitrogen oxides other than dinitrogen oxide
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2257/00—Components to be removed
- B01D2257/70—Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
- B01D2257/708—Volatile organic compounds V.O.C.'s
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
- B01J2229/10—After treatment, characterised by the effect to be obtained
- B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
- B01J2229/186—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself not in framework positions
Abstract
The catalyst takes an SBA-15 molecular sieve as a carrier and ferromanganese oxide as an active component, and adsorbs urea to obtain a urea-MnFe/SBA-15 catalyst; the invention also discloses a preparation method and application of the low-temperature low-oxygen tail gas denitration catalyst. When the catalyst is applied, the catalyst and the low-temperature plasma are combined, quartz wool and the catalyst are uniformly mixed and then are fixed in a reactor, and the pressure drop of a bed layer is reduced; urea is used as a reducing agent and is introduced into a catalyst to directly participate in reaction, and the high-energy active species is provided by matching with plasma bombardment reaction gas, so that the reaction temperature is reduced, and the high-efficiency removal of NO under the low-temperature and low-oxygen environment is realized. The whole denitration process is green and environment-friendly, has no secondary pollution and has wide application prospect.
Description
Technical Field
The invention belongs to the field of catalytic reaction processes, and relates to a catalyst for low-temperature low-oxygen tail gas denitration, a preparation method and application thereof.
Background
Nitrogen oxides (NO > 90%) as one of the major hazardous gases in atmospheric environmental pollution pose serious threats to both the environment and human health and must be properly handled. Among the numerous NO gas denitration technologies, the Selective Catalytic Reduction (SCR) method is widely used in industry due to its high denitration efficiency, and the reducing agents commonly used in the selective catalytic reduction denitration reaction are ammonia and urea.
For the SCR technology which is relatively mature in the prior art and takes ammonia as a reducing agent, the temperature of a reaction window is 300-450 ℃, but the emission temperature of flue gas is lower, and the flue gas needs to be reheated to carry out NH3-SCR reaction. Therefore, at low temperature (150 ℃), the denitration efficiency of the SCR technology is not high, the defects of complex process, high energy consumption and the like exist, ammonia escape is easy to occur in the reaction process, raw materials are consumed, and secondary pollution is caused. The SCR technology using urea as a reducing agent generally adds urea in the form of solution to react, and the urea is precipitated into NH3 at high temperature, which is also NH3-SCR in nature. The urea is loaded on the catalyst and directly reacts with NO at low temperature, so that the unstable decomposition of the urea can be effectively avoided, and the escape of ammonia is avoided. However, the method for drying the loaded urea after ordinary impregnation has low efficiency, and the urea recrystallization and concentrated precipitation of the catalyst can occur when the catalyst is kept still and dried, so that the actual loading effect can not be achieved.
Meanwhile, in the NH3-SCR technology, the content of oxygen has great influence on NO decomposition. The existing SCR catalyst with better performance works under the reaction condition of higher oxygen concentration. Higher concentrations of oxygen (10-20%) can effectively participate in the reaction, enhancing NO oxidation and promoting rapid SCR reactions. The lower the oxygen concentration is, the greater the influence on the low-temperature denitration continuation performance of the catalyst is, and the NO decomposition rate is greatly influenced in a low-oxygen and anaerobic environment. In order to save fuel and reduce energy consumption, when the oxygen content of the boiler flue gas is 3-5%, the combustion is most sufficient; meanwhile, the tail gas of the automobile is generally in a low oxygen state under the condition of full combustion. Therefore, there is a need to develop low temperature SCR catalysts for low temperature applications in low to no oxygen conditions.
Disclosure of Invention
The invention solves the problems in the prior art by providing the catalyst for low-temperature and low-oxygen tail gas denitration, the preparation method and the application thereof.
In order to achieve the purpose, the invention adopts the technical scheme that:
the invention provides a catalyst for low-temperature low-oxygen tail gas denitration, which takes an SBA-15 molecular sieve as a carrier and a ferromanganese oxide as an active component, and adsorbs urea to obtain a urea-MnFe/SBA-15 catalyst.
Preferably, the loading amount of the urea is 10-20%; the loading capacity of Mn is 10-20%; the load of Fe is 0.1-1%.
A preparation method of a catalyst for low-temperature and low-oxygen tail gas denitration comprises the following steps:
and 4, evaporating the solvent of the catalyst precursor system obtained in the step 3 to obtain the urea-MnFe/SBA-15 catalyst.
Preferably, in the step 1, the mass concentration of the manganese nitrate aqueous solution is 5-50 g/L; the mass concentration of the ferric nitrate water solution is 1-20 g/L.
Preferably, in the step 2, the roasting temperature is 400-700 ℃, and the roasting time is 4-6 h.
Preferably, in the step 4, the loading amount of the urea is 5-20%, the rotary evaporation temperature is 50-80 ℃, and the rotating speed is 40-100 rpm; the loading capacity of Mn is 10-20%, and the loading capacity of Fe is 0.1-1%.
The application of the catalyst for low-temperature low-oxygen tail gas denitration is characterized in that the urea-MnFe/SBA-15 catalyst is combined with low-temperature plasma and fixed to a discharge area of a reactor in a mode of uniformly mixing quartz wool with the catalyst.
Preferably, 0-5% of O at low temperature of 25-50 DEG C2Hypoxic ring of contentThe catalytic decomposition reaction of NO is carried out.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a catalyst for low-temperature low-oxygen tail gas denitration, which is prepared by loading SBA-15 molecular sieve serving as a carrier and transition metals of Mn and Fe serving as active components on SBA-15 and finally doping urea; the manganese and iron in the ferromanganese double catalyst have a synergistic effect and have better catalytic activity than single metal thereof; meanwhile, the manganese and the iron are low in price and convenient to obtain, and the preparation cost of the catalyst is greatly reduced; the doped urea directly participates in the reaction and can effectively replace a reducing agent (NH) in the SCR method3) The introduction of the catalyst improves the NO decomposition efficiency and avoids secondary pollution such as ammonia escape.
The invention provides a preparation method of a catalyst for low-temperature and low-oxygen tail gas denitration, manganese and iron double metals are loaded on an SBA-15 molecular sieve carrier by adopting an excess impregnation method, urea has the problem of decomposition at an excessively high temperature during loading, and if an air-blast drying box is adopted for standing and drying, part of urea particles can be recrystallized and separated out at the junction of the catalyst and a cup wall. Therefore, firstly, an ultrasonic stirring method is adopted to fully mix the urea solution and the catalyst system; dipping for more than 10h at normal temperature to ensure that the urea is fully loaded in the catalyst. And finally, slowly evaporating the solvent by using a rotary evaporator at 50-80 ℃, so that the decomposition of urea and the concentrated recrystallization precipitation can be effectively avoided.
The application of the catalyst for low-temperature low-oxygen tail gas denitration provided by the invention is that the existing low-temperature plasma is taken as an environment-friendly treatment technology and is widely applied to the removal process of harmful gases such as greenhouse gases, VOCs (volatile organic chemicals), NOx and the like. However, the existing technology for directly removing nitrogen oxides by using low-temperature plasma has the problems of high energy consumption and high cost. If the catalyst catalysis is combined with the low-temperature plasma technology, on one hand, NO molecules in the reaction atmosphere are bombarded by the plasma to form a large number of active species even in a low-oxygen or even oxygen-free environment, and the high-activity ionized oxygen generated in the process can effectively promote NO to be oxidized into NO2, so that the rapid SCR reaction is generated, and the NO removal efficiency is improved; on the other hand, the catalytic action of the catalyst can reduce the reaction energy barrier, the energy consumption of the plasma can be reduced when the catalyst and the plasma act cooperatively, and meanwhile, the high-energy electrons can enable poisoning substances accumulated on the catalyst to be bombarded, so that the working time of the catalyst is prolonged. When the catalyst is combined with the plasma reaction, the catalyst and a proper amount of quartz wool are uniformly mixed and then fixed to a discharge area of the dielectric barrier plasma reactor, so that the compression and accumulation of the catalyst are reduced, and the problems that the pressure drop before and after the catalyst in the reactor is too large and the gas flow is reduced are avoided.
Drawings
FIG. 1 is a schematic view of a plasma reactor according to the present invention;
FIG. 2 is a schematic illustration of a fixed position of a catalyst according to the present invention;
FIG. 3 is a graph showing the results of catalytic decomposition of NO in a low temperature plasma reactor in the absence of oxygen for a catalyst according to the present invention;
FIG. 4 is a graph showing the result of catalytic decomposition of NO at different voltages under the synergistic effect of the catalyst of the present invention and low temperature plasma;
FIG. 5 is a graph showing the result of catalytic decomposition of NO at different voltages under the synergistic effect of the catalyst and the low-temperature plasma according to the present invention;
wherein, the device comprises a corundum tube plasma reactor 1, a corundum tube plasma reactor 2, a high-voltage discharge electrode 3, a tube furnace 4, a temperature controller 5, a high-voltage power supply 6, quartz wool 7 and urea-MnFe/SBA-15.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The invention provides a catalyst for low-temperature lean oxygen tail gas denitration, which is formed by taking an SBA-15 molecular sieve as a carrier, taking Mn and Fe as active components to be loaded on the SBA-15 and doping urea (urea), and is marked as a urea-MnFe/HAP catalyst, wherein the urea loading amount is 10-20%, the Mn loading mass fraction is 10-20%, and the Fe loading mass fraction is 0.1-1%.
A preparation method of a urea-doped bimetallic catalyst comprises the following steps:
the concentration of the aqueous manganese nitrate solution is preferably 20g/L, and the concentration of the aqueous iron nitrate solution is preferably 10 g/L.
And 2, standing and aging the mixed solution obtained in the step 1 until the active component is fully adsorbed on the surface of the carrier to obtain a system, and then drying the obtained system in an oven to obtain powder.
When the load mass fraction of Mn is 15%, the NO removal effect is the most excellent when the load mass fraction of Fe is 0.56%.
And 4, dropwise adding a urea (urea) solution with a certain concentration into the system obtained in the step 3, fully stirring, and standing until the urea is fully adsorbed on the catalyst to obtain a catalyst precursor system.
And 5, evaporating the catalyst precursor system obtained in the step 4 to dryness in a rotary evaporator at the temperature of 50-80 ℃ and the rotating speed of 40-100 rpm to obtain the urea-MnFe/SBA-15 catalyst. Wherein the loading amount of the urea is 5-20%. When the urea loading mass fraction is 15%, the NO removal effect is optimal, and when the rotary evaporator rotates at 60 ℃ and 60rpm, the urea loading condition is best.
As shown in fig. 1 and 2, the application of a urea-doped bimetallic catalyst combines a urea-MnFe/SBA-15 catalyst and low-temperature plasma to perform a catalytic decomposition reaction of NO, specifically:
mixing urea-MnFe/SBA-15 catalyst by using quartz wool to play a role of a dispersing agent, fixing the catalyst in a corundum tube plasma reactor 1, introducing 300ppm of NO gas into the corundum tube plasma reactor 1, and performing a dielectric barrier discharge plasma concerted catalytic decomposition reaction of NO by using He as a carrier gas; wherein the flow rate of the NO-He mixed gas is 60-200 mL/min, and the reaction temperature is 20-250 ℃;
the corundum tube plasma reactor 1 is of a tubular structure with the inner diameter of 5-2000 mm, a high-voltage discharge electrode 2 is placed in the corundum tube plasma reactor, the high-voltage discharge electrode 2 is a copper electrode with the diameter of 2-1800 mm, the peak value of discharge voltage is 0-30V, and the discharge frequency is 5-50 kHz. Among them, the discharge voltage is optimum at 10V, and the discharge frequency is optimum at 10 kHz.
Meanwhile, the corundum tube plasma reactor 1 is arranged in a tubular furnace 3, and the tubular furnace 3 is connected with a temperature controller 4 for controlling the reaction temperature of the corundum tube plasma reactor 1. The high-voltage discharge electrode 2 of the corundum tube plasma reactor 1 is connected with a high-voltage power supply 5. The gas inlet of the plasma reactor 1 is connected with a NO-He mixed gas pipeline, and the gas outlet of the reactor is connected with a flue gas analyzer.
The urea-MnFe/SBA-15 catalyst is fixed in a discharge area in the corundum tube plasma reactor or behind the discharge area, and the plasma and the catalyst can be more tightly combined by fixing the catalyst in the discharge area.
Example 1
A preparation method of a urea-doped bimetallic catalyst comprises the following steps:
And 3, roasting the powder obtained in the step 2 in a muffle furnace at 500 ℃ for 4h to obtain the MnFe/SBA-15 catalyst.
The reaction is carried out in a quartz tube reactor, urea-MnFe/SBA-15 catalyst is dispersed and mixed by quartz wool and is fixed in the reactor, and the reaction gas is 300ppm NO and 5 percent O2Ar is carrier gas, the total gas volume is 120mL/min, and the reaction temperature is 25-200 ℃. As shown in FIG. 3, the NO concentration at the reaction outlet was 11ppm and the removal efficiency was 96% at 200 ℃.
Example 2
A preparation method of a urea-doped bimetallic catalyst comprises the following steps:
And 3, roasting the powder obtained in the step 2 in a muffle furnace at 500 ℃ for 4h to obtain the MnFe/SBA-15 catalyst.
The reaction is carried out in a quartz tube reactor, urea-MnFe/SBA-15 catalyst is dispersed and mixed by quartz wool and is fixed in the reactor, 300ppm of NO gas is introduced into the reactor, and Ar is used as carrier gas to carry out NO decomposition reaction. Wherein, as shown in FIG. 4, in an oxygen-free environment, when the reaction temperature is below 100 ℃, the NO decomposition rate is not high; and after the temperature reaches 150 ℃, the NO decomposition efficiency is obviously improved, and at 250 ℃, the NO concentration at a reaction outlet is only 5ppm, and the removal efficiency reaches more than 98%.
Example 3
A preparation method of a urea-doped bimetallic catalyst comprises the following steps:
And 3, roasting the powder obtained in the step 2 in a muffle furnace at 500 ℃ for 4h to obtain the MnFe/SBA-15 catalyst.
Claims (8)
1. A catalyst for low-temperature and low-oxygen tail gas denitration is characterized in that an SBA-15 molecular sieve is used as a carrier, a ferromanganese oxide is used as an active component, and urea is adsorbed to obtain a urea-MnFe/SBA-15 catalyst.
2. The catalyst for low-temperature low-oxygen tail gas denitration according to claim 1, wherein the loading amount of urea is 10-20%; the loading capacity of Mn is 10-20%; the load of Fe is 0.1-1%.
3. A preparation method of a catalyst for low-temperature and low-oxygen tail gas denitration is characterized by comprising the following steps:
step 1, dripping a manganese nitrate aqueous solution, a ferric nitrate aqueous solution and deionized water into an SBA-15 molecular sieve carrier in sequence, and stirring to fully mix the manganese nitrate aqueous solution, the ferric nitrate aqueous solution and the deionized water to obtain a mixed solution;
step 2, standing and aging the mixed solution obtained in the step 1 until active components are fully adsorbed on the surface of a carrier to obtain a system, and then drying and roasting the obtained system to obtain a MnFe/SBA-15 system;
step 3, dripping a urea solution into the MnFe/SBA-15 system obtained in the step 2, stirring and standing until the urea is fully adsorbed on the catalyst to obtain a catalyst precursor system;
and 4, evaporating the solvent of the catalyst precursor system obtained in the step 3 to obtain the urea-MnFe/SBA-15 catalyst.
4. The preparation method of the catalyst for low-temperature low-oxygen tail gas denitration according to claim 3, wherein in the step 1, the mass concentration of the manganese nitrate aqueous solution is 5-50 g/L; the mass concentration of the ferric nitrate water solution is 1-20 g/L.
5. The preparation method of the catalyst for low-temperature low-oxygen tail gas denitration according to claim 3, wherein in the step 2, the roasting temperature is 400-700 ℃, and the roasting time is 4-6 h.
6. The urea-doped bimetallic catalyst of claim 3, wherein in the step 4, the loading amount of urea is 5-20%, the rotary evaporation temperature is 50-80 ℃, and the rotation speed is 40-100 rpm; the loading capacity of Mn is 10-20%, and the loading capacity of Fe is 0.1-1%.
7. Use of the catalyst for low-temperature low-oxygen exhaust gas denitration according to claim 1 or 2, wherein the urea-MnFe/SBA-15 catalyst according to claim 1 is combined with low-temperature plasma and fixed to the discharge region of the reactor by uniformly mixing quartz wool with the catalyst.
8. The application of the catalyst for low-temperature low-oxygen tail gas denitration according to claim 7, which is characterized in that the catalyst is 0-5% of O at a low temperature of 25-50 DEG C2The catalytic decomposition reaction of NO is carried out under the low-oxygen environment with the content.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110674855.2A CN113457717A (en) | 2021-06-17 | 2021-06-17 | Catalyst for low-temperature low-oxygen flue gas denitration, preparation method and application thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110674855.2A CN113457717A (en) | 2021-06-17 | 2021-06-17 | Catalyst for low-temperature low-oxygen flue gas denitration, preparation method and application thereof |
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