CN116099541B - Preparation of iron-based perovskite catalyst rich in oxygen vacancies and efficient NO removal method thereof - Google Patents
Preparation of iron-based perovskite catalyst rich in oxygen vacancies and efficient NO removal method thereof Download PDFInfo
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 84
- 239000003054 catalyst Substances 0.000 title claims abstract description 50
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 48
- 239000001301 oxygen Substances 0.000 title claims abstract description 48
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 48
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 40
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000002360 preparation method Methods 0.000 title claims description 8
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims abstract description 39
- 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 abstract description 28
- 238000006243 chemical reaction Methods 0.000 claims abstract description 27
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000004202 carbamide Substances 0.000 claims abstract description 21
- FYDKNKUEBJQCCN-UHFFFAOYSA-N lanthanum(3+);trinitrate Chemical compound [La+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O FYDKNKUEBJQCCN-UHFFFAOYSA-N 0.000 claims abstract description 19
- 230000001590 oxidative effect Effects 0.000 claims abstract description 7
- 239000008139 complexing agent Substances 0.000 claims abstract description 5
- 229910052751 metal Inorganic materials 0.000 claims abstract description 5
- 239000002184 metal Substances 0.000 claims abstract description 5
- 150000003839 salts Chemical class 0.000 claims abstract description 5
- 239000000779 smoke Substances 0.000 claims abstract description 5
- 238000009834 vaporization Methods 0.000 claims abstract description 3
- 230000008016 vaporization Effects 0.000 claims abstract description 3
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 14
- 239000003546 flue gas Substances 0.000 claims description 14
- 230000004913 activation Effects 0.000 claims description 13
- 238000010521 absorption reaction Methods 0.000 claims description 8
- 239000007789 gas Substances 0.000 claims description 7
- 238000003756 stirring Methods 0.000 claims description 7
- 238000001514 detection method Methods 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- 239000003344 environmental pollutant Substances 0.000 claims description 4
- 231100000719 pollutant Toxicity 0.000 claims description 4
- 238000007605 air drying Methods 0.000 claims description 3
- 238000001354 calcination Methods 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- 239000008367 deionised water Substances 0.000 claims description 3
- 229910021641 deionized water Inorganic materials 0.000 claims description 3
- 239000003337 fertilizer Substances 0.000 claims description 3
- 238000000227 grinding Methods 0.000 claims description 3
- 238000011068 loading method Methods 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 239000012159 carrier gas Substances 0.000 claims description 2
- 238000003795 desorption Methods 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 229910021645 metal ion Inorganic materials 0.000 claims description 2
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 238000004064 recycling Methods 0.000 claims description 2
- 229910017771 LaFeO Inorganic materials 0.000 abstract description 15
- 230000001105 regulatory effect Effects 0.000 abstract description 5
- 239000007800 oxidant agent Substances 0.000 abstract description 4
- 238000003980 solgel method Methods 0.000 abstract description 4
- 239000000463 material Substances 0.000 abstract description 3
- 238000003746 solid phase reaction Methods 0.000 abstract description 2
- 239000011152 fibreglass Substances 0.000 abstract 1
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 94
- 230000000694 effects Effects 0.000 description 7
- 230000007547 defect Effects 0.000 description 6
- 230000003197 catalytic effect Effects 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 150000001768 cations Chemical class 0.000 description 4
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical compound [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 description 4
- 229910001981 cobalt nitrate Inorganic materials 0.000 description 4
- 239000010453 quartz Substances 0.000 description 4
- 239000003642 reactive oxygen metabolite Substances 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 238000011049 filling Methods 0.000 description 3
- 238000004435 EPR spectroscopy Methods 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 238000009303 advanced oxidation process reaction Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000012855 volatile organic compound Substances 0.000 description 2
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 229910002588 FeOOH Inorganic materials 0.000 description 1
- 239000012028 Fenton's reagent Substances 0.000 description 1
- 229910021193 La 2 O 3 Inorganic materials 0.000 description 1
- 229910002182 La0.7Sr0.3MnO3 Inorganic materials 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000809 air pollutant Substances 0.000 description 1
- 231100001243 air pollutant Toxicity 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 239000007809 chemical reaction catalyst Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 150000001868 cobalt Chemical class 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- -1 fe 0 Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000001727 in vivo Methods 0.000 description 1
- 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
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000002826 nitrites Chemical class 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
Classifications
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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
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
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- 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
- B01D53/46—Removing components of defined structure
- B01D53/54—Nitrogen compounds
- B01D53/56—Nitrogen oxides
-
- 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
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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
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/002—Mixed oxides other than spinels, e.g. perovskite
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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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/03—Precipitation; Co-precipitation
- B01J37/036—Precipitation; Co-precipitation to form a gel or a cogel
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/10—Oxidants
- B01D2251/106—Peroxides
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/02—Other waste gases
- B01D2258/0283—Flue gases
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
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Abstract
Iron-based perovskite (LaFeO) rich in oxygen vacancies 3 ) The catalyst is prepared by a urea-regulated sol-gel method, citric acid is used as a complexing agent, lanthanum nitrate and ferric nitrate are used as metal salts, and LaFeO is modified by urea treatment 3 The La vacancy in the glass fiber reinforced plastic material increases the oxygen vacancy quantity; simulated smoke carrying vaporization H 2 O 2 Entering a fixed bed reactor to perform gas-solid phase reaction with a catalyst in the reactor; h 2 O 2 Activated by the iron-based perovskite catalyst rich in oxygen vacancies to generate a large amount of active oxygen species, so that NO is efficiently oxidized and removed; h is added in the reaction process 2 O 2 As an environment-friendly oxidant, the secondary pollution in the reaction process is avoided, and SO 2 The denitration efficiency of the iron-based perovskite catalyst rich in oxygen vacancies can be improved, the method can be suitable for various complex working condition environments, and a feasibility scheme is provided for solving NO pollution.
Description
Technical Field
The invention belongs to the technical field of flue gas purification, and in particular relates to preparation of an iron-based perovskite catalyst rich in oxygen vacancies and activation H thereof 2 O 2 A high-efficiency denitration method.
Background
Nitrogen Oxides (NO) x Wherein the NO content is about95%) is one of main air pollutants, is one of important precursors causing pollutants such as ozone, particulate matters, photochemical smog, haze and the like, and forms a great threat to regional environment and human health. At present, NH 3 Selective catalytic reduction (NH) 3 SCR) denitration technology is widely applied due to high removal efficiency, but is difficult to be applied to medium and small industrial boilers with complex working conditions due to the defects of high operation and maintenance cost, large occupied area, narrow applicable flue gas temperature range (300-400 ℃), and the like. Therefore, there is an urgent need to develop a denitration method that is efficient, low-cost, and suitable for various operation conditions.
Advanced Oxidation Processes (AOP) are considered to be an effective method for achieving efficient removal of NO under complex conditions. When combined with Wet Flue Gas Desulfurization (WFGD) technology, the NO concentration can be reduced to 50mg/m 3 The following are set forth; can oxidize NO into soluble high-valence nitrogen oxides, such as NO which can be used as raw material of primary compound fertilizer 3 - . Fenton reagent (H) 2 O 2 ) Because of low cost, wide application range, no secondary pollution and capability of generating high Reactive Oxygen Species (ROS), namely OH and O 2 · - And 1 O 2 and is of great concern. Classical Fenton reactions are generally carried out under homogeneous conditions, limited by stringent pH requirements (. Apprxeq.3) and by the large production of iron sludge. In contrast, heterogeneous Fenton-like systems show a greater application prospect, wherein Fe-based materials (e.g., fe 0 、Fe 2 O 3 And FeOOH, etc.) are widely used for Fenton-like catalysts due to their abundant resources, environmental friendliness, and good activity. Although these iron-based materials exhibit high catalytic activity against H 2 O 2 The utilization rate is low, and a large amount of H still needs to be consumed in the denitration process 2 O 2 The method comprises the steps of carrying out a first treatment on the surface of the Therefore, the development of high activity iron-based Fenton-like catalysts is still of paramount importance.
ABO 3 Perovskite oxides have been widely used as Fenton-like catalysts for the treatment of gaseous pollutants, including Volatile Organic Compounds (VOCs) degradation, CO oxidation, NO reduction, and the like, due to their advantages of high cost effectiveness, good stability, easy synthesis, and the like. It is well known that A-site doping/substitution in perovskite may be evidentThe perovskite oxide is well regulated in vivo/surface properties, thereby improving its catalytic performance. For example, using a series of cobalt-based perovskite catalysts ACoO having different cations in the A-position 3 (a=la, ba, sr and Ce) to activate PMS to degrade phenol, the activity of which is related to cation at a-position, the related order being SrCoO 3 >LaCoO 3 >BaCoO 3 >CeCoO 3 . In addition, A-site doping has also been shown to affect the catalytic activity of perovskite oxides and the ability to activate Fenton-like reagents, such as Ce doped in Sr 1-x Ce x FeO 3 Wherein Sr is doped in L a0.5 Sr 0.5 FeO 3 PMS and La 0.7 Sr 0.3 MnO 3 In the/PDS system, and Ti is doped in La x Ti y FeO 3 /H 2 O 2 In the system. The a-site doping strategy can improve the performance of the perovskite to some extent, but is limited by the low solubility of many elements in the perovskite oxide and the tolerance factors that determine perovskite structure formation. At the same time, researchers have also found that introducing a-site defects into the perovskite lattice structure can significantly increase the surface oxygen defects of perovskite catalysts, such as the selective removal of LaMnO by acid treatment 3 The A-site cations in the (2) are exposed to the active B-site cations, thereby improving the oxidation rate of CO. In addition, non-stoichiometric strategy-generated A-site defects can also enhance La x MnO 3 、La 1.15 MnO 3+δ PMS and La x FeO 3 /H 2 O 2 This can be attributed to surface oxygen vacancies (Ov) and the generation of large amounts of reactive oxygen species. From the above, it is apparent that ABO is found 3 The importance of the A-site defect in the perovskite, therefore, an economic and environment-friendly method is developed to regulate the A-site vacancy of the perovskite, thereby efficiently catalyzing H 2 O 2 The generation of more reactive oxygen species is of great importance.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides the preparation of the iron-based perovskite catalyst rich in oxygen vacancies and the activation H thereof 2 O 2 Efficient denitration method, and iron-based perovskite catalysis method rich in oxygen vacanciesThe chemical agent is prepared by sol-gel method, and LaFeO is modified by simple urea treatment 3 The La vacancies in the glass are increased, and the increase of the surface oxygen vacancies is confirmed by an Electron Paramagnetic Resonance (EPR) technology. The oxygen vacancy-enriched iron-based perovskite catalyst activates H 2 O 2 High-efficient denitration system, including flue gas generating device, H 2 O 2 An activation and denitration reaction device and a tail gas detection and absorption device.
Specifically, in a first aspect of the present invention, a method for preparing an iron-based perovskite catalyst rich in oxygen vacancies is provided, comprising the steps of:
(1) Dissolving a certain amount of lanthanum nitrate, ferric nitrate and urea into a proper amount of deionized water;
(2) Magnetically stirring the solution at room temperature for at least 3 hours;
(3) Adding a certain amount of citric acid into the obtained solution, and magnetically stirring at 80 ℃ until the solution is gel;
(4) Immediately placing the obtained gel in a forced air drying oven, and drying at 110deg.C for at least 10 hr;
(5) Grinding the dried sample, then placing the ground sample into a muffle furnace, and calcining the ground sample at 700 ℃ for 5 hours to obtain the iron-based perovskite catalyst rich in oxygen vacancies.
In the preparation method, the citric acid is a complexing agent, and the lanthanum nitrate and the ferric nitrate are metal salts; the dosage of lanthanum nitrate and cobalt nitrate is the same; the optimal dosage of urea is 2-3 times of the dosage of lanthanum nitrate and cobalt nitrate, and the dosage of citric acid is 1-2 times of the dosage of lanthanum nitrate and cobalt nitrate.
In a second aspect of the present invention, there is provided an oxygen vacancy-rich iron-based perovskite catalyst as prepared by the first aspect of the present invention, establishing an activated H 2 O 2 The high-efficient NO system that desorption includes: flue gas generating device, H 2 O 2 An activation and denitration reaction device and a tail gas detection and absorption device.
Activation of H by the above oxygen vacancy-rich iron-based perovskite catalyst 2 O 2 In the high-efficiency NO removal system, the H 2 O 2 As an environment-friendly oxidant, no secondary pollution is generated in the using reaction process.
Activation of H by the above oxygen vacancy-rich iron-based perovskite catalyst 2 O 2 In the high-efficiency NO removal system, H in the reaction process 2 O 2 The optimal use concentration is 5wt.%.
In a third aspect of the present invention, there is provided an oxygen vacancy-rich iron-based perovskite catalyst prepared by using the first aspect of the present invention, activating H 2 O 2 The high-efficiency denitration method comprises the following steps:
(1) H is supplied by a heating jacket 2 O 2 After vaporization, the simulated flue gas is reused to vaporize H 2 O 2 Loading into a fixed bed reactor;
(2) Carrying vaporised H 2 O 2 Is introduced into the reactor, and the iron-based perovskite catalyst rich in oxygen vacancies activates H 2 O 2 Generating a large amount of active oxygen species, and further oxidizing and removing NO;
(3) By Na 2 SO 3 The absorbing liquid absorbs tail flue gas to obtain primary raw materials (nitrate and nitrite) of the common compound fertilizer, and can realize the recycling utilization of pollutants.
Activation of H by the above-mentioned oxygen vacancy-rich iron-based perovskite catalyst 2 O 2 In the method for efficiently removing NO, the absorption liquid is 3wt.% Na 2 SO 3 A solution.
In a fourth aspect of the present invention, there is provided an oxygen vacancy-rich iron-based perovskite catalyst prepared by the first aspect of the present invention, activated by H 2 O 2 The operating conditions for removing NO by oxidation include the following steps:
(1) The gas speed of the nitrogen carrier gas is 60L/h;
(2) The reaction temperature is 90-210 ℃;
(3) The catalyst dosage is 0.1g;
(4)H 2 O 2 the concentration is 1wt.% to 9wt.%;
(5) The molar ratio of urea addition was 1,2.5,3.5 and 5 (molar ratio of urea to total metal ions);
(6) The initial concentration of NO is 750mg/m 3 ；
(7) Space velocity is 480000h -1 ；
(8)O 2 Concentrations of 2% and 10% (v/v);
(9)SO 2 the concentration is 750 and 3000 (mg/m) 3 )；
(8)CO 2 The concentrations were 2% and 10% (v/v).
The beneficial effects of the invention are as follows:
1. the invention successfully improves LaFeO by a simple urea regulation method 3 The number of oxygen vacancies in the LaFeO is enhanced 3 Catalytic performance and activation of H 2 O 2 Capability.
2. The invention utilizes the iron-based perovskite rich in oxygen vacancies to activate H 2 O 2 Denitration can not only efficiently activate H 2 O 2 Generates a large amount of active oxygen species, obviously improves H 2 O 2 Utilization rate; the NO high-efficiency denitration can be realized at a lower temperature; and H is 2 O 2 As an environment-friendly oxidant, no secondary pollution is generated in the using process.
3、SO 2 Not only does not inhibit the denitration performance of the iron-based perovskite rich in oxygen vacancies, but also improves the NO removal efficiency to a certain extent; and good NO removal efficiency can be maintained at high airspeed. The invention provides the iron-based perovskite activation H rich in oxygen vacancies 2 O 2 The high-efficiency denitration system can be suitable for various complex working condition environments, and a feasibility scheme is provided for solving NO pollution.
Drawings
FIG. 1 is a flow chart of an iron-based perovskite catalyst preparation rich in oxygen vacancies;
FIG. 2 shows LaFeO 3 And urea regulated LaFeO 3 (2.5U-LaFeO 3 ) Electron paramagnetic resonance characterization map.
Detailed Description
The invention provides an iron-based perovskite catalyst activation H rich in oxygen vacancies 2 O 2 High-efficiency denitration methodThe iron-based perovskite rich in oxygen vacancies is prepared by a simple urea-regulated sol-gel method, and is used for efficiently activating H 2 O 2 The denitration system comprises a smoke generating device and H 2 O 2 An activation and denitration reaction device and a tail gas detection and absorption device; the following is a further detailed description of the embodiments:
example 1
The iron-based perovskite catalyst rich in oxygen vacancies is prepared by a simple urea-regulated sol-gel method:
the catalyst takes citric acid as a complexing agent, and lanthanum nitrate and ferric nitrate as metal salts; the dosage of lanthanum nitrate and cobalt nitrate is 0.006mol respectively; the urea dosage is 0.012,0.030,0.042 and 0.060mol, and the citric acid dosage is 0.0132mol; stirring temperature is 80 ℃, drying temperature is 110 ℃, and roasting time is 700 ℃ for 5 hours.
Lanthanum nitrate, iron nitrate, urea and citric acid were used in amounts shown in table 1:
TABLE 1
Example 2
The method of the invention is that a quartz tube of a tube furnace device is filled with a catalyst to form a reaction bed, and the simulated flue gas carries vaporized H 2 O 2 And (3) carrying out gas-solid phase reaction with the catalyst through the fixed reaction bed so as to remove NO. The in-reaction catalyst was an iron-based perovskite catalyst rich in oxygen vacancies prepared in example 1. The catalyst is filled in a quartz tube, and when simulated flue gas carries vaporized H 2 O 2 H when passing through the reaction bed 2 O 2 React with the catalyst under the action of thermal catalysis to generate a large amount of active oxygen species, and NO is oxidized into NO by the active oxygen species 3 - And NO 2 - Further absorbed by tail absorption liquid and converted into nitric acidSalts and nitrites.
In this example, the simulated flue gas consisted of 1000mg/m 3 N 2 And 750mg/m 3 NO composition. The tail gas detection device is a multifunctional smoke analyzer produced by German RBR company. The quartz tube reactor was about 400mm long, about 10mm inside diameter and about 16mm outside diameter.
The catalyst is filled into a quartz tube of the reactor device to form a reaction bed layer, and the simulated flue gas is subjected to an oxidation NO removal reaction through the catalyst bed layer. Catalyst loading was 0.1g, reaction temperature 120℃and initial NO concentration 750mg/m 3 ，H 2 O 2 The concentration was 3wt.%. The oxidation and denitration experiment was performed by changing the kind of the catalyst, and the results are shown in table 2.
TABLE 2
With La 2 O 3 、Fe 3 O 4 、Fe 2 O 3 And LaFeO 3 In contrast, oxygen vacancy-rich iron-based perovskite catalyst (2.5U-LaFeO 3 ) The NO removal efficiency can be obviously improved, and the denitration efficiency can be up to 80.53%.
Example 3
In this example, the initial concentration of NO was 750mg/m 3 ，H 2 O 2 The concentration was 3wt.%, the volume space velocity was 480000h -1 The reaction temperature was 120 ℃. The effect of different urea ratios on the NO removal efficiency was examined by varying the urea ratio and the results are shown in Table 3.
TABLE 3 Table 3
With the increase of the proportion of urea, the NO removal efficiency is firstly increased and then decreased, and the optimal NO removal efficiency is 80.53 percent and is formed by 2.5U-LaFeO 3 The catalyst is preferably 2.5U-LaFeO 3 。
Example 4
In this example, 2.5U-LaFeO 3 The filling amount is 0.1g, and the initial concentration of NO is 750mg/m 3 Volume space velocity is 480000h -1 The reaction temperature was 120 ℃. Change H during the experiment 2 O 2 The concentrations were 1wt.%, 3wt.%, 5wt.%, 7wt.%, 9wt.%, H was examined 2 O 2 The effect of concentration on denitration efficiency is shown in table 4.
TABLE 4 Table 4
When H is 2 O 2 The concentration increased from 1wt.% to 9wt.%, and the denitration efficiency increased from 41.2% to 96.10%. When H is 2 O 2 When the concentration is more than 5wt.%, H is increased 2 O 2 The concentration is not obvious for improving the denitration efficiency; comprehensively consider the removal efficiency and economic benefit, H 2 O 2 The concentration is preferably 5wt.%.
Example 5
In this example, 2.5U-LaFeO 3 The filling amount is 0.1g, and the initial concentration of NO is 750mg/m 3 ,H 2 O 2 The concentration was 5wt.%, the volume space velocity was 480000h -1 . The reaction temperature was adjusted so that the reaction bed temperature was maintained at 90℃at 120℃at 150℃at 180℃and at 210℃and the results of the catalytic oxidative denitration experiments were shown in Table 5.
TABLE 5
The NO removal efficiency is firstly increased and then decreased along with the reaction temperature, and the optimal NO removal efficiency is 89.12 percent and is obtained at 120 ℃. The NO removal efficiency is more than 70% in the reaction temperature range of 90-210 ℃.
Example 6
In this example, 2.5U-LaFeO 3 The filling amount is 0.1g, H 2 O 2 The concentration was 5wt.%, the volume space velocity was 480000h -1 The reaction temperature was 120 ℃. This practice isIn the embodiment, O is changed respectively 2 Initial concentration of 2% and 5% (v/v), SO 2 The concentration is 750mg/m 3 And 3000mg/m 3 ，CO 2 The concentrations were 2% and 10% (v/v), and the effect of the smoke components on the NO removal efficiency was examined, and the experimental results are shown in Table 6.
TABLE 6
O 2 The removal of NO is slightly inhibited. When O is 2 The concentration increased from 2% to 10% and the NO removal efficiency decreased from 85.04% to 82.66%. SO (SO) 2 Has a certain promotion effect on NO removal, when SO 2 The concentration is 750mg/m 3 Increased to 3000mg/m 3 When the NO removal efficiency increased from 89.96% to 92.12%. CO 2 Also inhibit NO removal when CO 2 The NO removal efficiency was reduced from 83.57% to 76.19% when the concentration was increased from 2% to 10%.
As can be seen from the results of the above specific examples, the invention realizes the efficient removal of NO in the coal-fired flue gas, and H is added in the reaction process 2 O 2 As an environment-friendly oxidant, the secondary pollution in the reaction process is avoided, and SO 2 Can improve the denitration efficiency of the iron-based perovskite catalyst rich in oxygen vacancies. The iron-based perovskite catalyst activation H rich in oxygen vacancies provided by the invention 2 O 2 The high-efficiency denitration system can be suitable for various complex working condition environments, and a feasibility scheme is provided for solving NO pollution.
Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the claims of the present application.
Claims (3)
1. Oxygen vacancy-enriched iron-based perovskite catalyst activated H 2 O 2 The high-efficient desorption NO system, its characterized in that includes: flue gas generating device, H 2 O 2 An activation and denitration reaction device and a tail gas detection and absorption device;
the activated H 2 O 2 System for efficiently removing NO and H in reaction process 2 O 2 The use concentration was 5 wt%;
the preparation method of the iron-based perovskite catalyst rich in oxygen vacancies comprises the following steps:
(1) Dissolving a certain amount of lanthanum nitrate, ferric nitrate and urea into a proper amount of deionized water;
(2) Magnetically stirring the solution at room temperature for at least 3 hours;
(3) Adding a certain amount of citric acid into the obtained solution, and magnetically stirring at 80 ℃ until the solution is gel;
(4) Immediately placing the obtained gel in a forced air drying oven, and drying at 110deg.C for at least 10 hr;
(5) Grinding the dried sample, placing into a muffle furnace, calcining at 700deg.C for at least 5 hr, and making
Obtaining the iron-based perovskite catalyst rich in oxygen vacancies;
the citric acid is a complexing agent, and the lanthanum nitrate and the ferric nitrate are metal salts; the dosage of lanthanum nitrate and ferric nitrate is the same; the urea is 2-3 times of lanthanum nitrate and ferric nitrate, and the citric acid is 1-2 times of lanthanum nitrate and ferric nitrate.
2. Activated H established by utilizing iron-based perovskite catalyst rich in oxygen vacancies 2 O 2 The high-efficiency denitration method is characterized by comprising the following steps of:
(1) H is supplied by a heating jacket 2 O 2 After vaporization, the simulated flue gas is reused to vaporize H 2 O 2 Loading into a fixed bed reactor;
(2) Carrying vaporised H 2 O 2 Is introduced into the reactor, and the iron-based perovskite catalyst rich in oxygen vacancies activates H 2 O 2 Generating a large amount of active oxygen species, and further oxidizing and removing NO;
(3) By Na 2 SO 3 Absorbing tail smoke by the absorption liquid to obtain a primary raw material of the common compound fertilizer, so as to realize the recycling of pollutants;
the absorption liquid is 3wt percent of Na 2 SO 3 A solution;
the preparation method of the iron-based perovskite catalyst rich in oxygen vacancies comprises the following steps:
(1) Dissolving a certain amount of lanthanum nitrate, ferric nitrate and urea into a proper amount of deionized water;
(2) Magnetically stirring the solution at room temperature for at least 3 hours;
(3) Adding a certain amount of citric acid into the obtained solution, and magnetically stirring at 80 ℃ until the solution is gel;
(4) Immediately placing the obtained gel in a forced air drying oven, and drying at 110deg.C for at least 10 hr;
(5) Grinding the dried sample, placing into a muffle furnace, calcining at 700deg.C for at least 5 hr, and making
Obtaining the iron-based perovskite catalyst rich in oxygen vacancies;
the citric acid is a complexing agent, and the lanthanum nitrate and the ferric nitrate are metal salts; the dosage of lanthanum nitrate and ferric nitrate is the same; the urea is 2-3 times of lanthanum nitrate and ferric nitrate, and the citric acid is 1-2 times of lanthanum nitrate and ferric nitrate.
3. Establishing activated H with an oxygen vacancy-rich iron-based perovskite catalyst according to claim 2 2 O 2 A high-efficiency denitration method is characterized in that an activated H is established 2 O 2 The operating conditions of the efficient denitration are as follows:
(1) The gas speed of the nitrogen carrier gas is 60L/h;
(2) The reaction temperature is 90-210 ℃;
(3) The catalyst dosage is 0.1g;
(4) H 2 O 2 the concentration is 1 wt-9 wt%;
(5) The molar ratio of urea to total metal ions was 2.5;
(6) An initial concentration of NO of 750mg/m 3 ；
(7) Space velocity of 480000h -1 ；
(8) O 2 Concentrations of 2% and 10% v/v;
(9) SO 2 the concentration is 750 and 3000mg/m 3 ；
(10) CO 2 The concentrations were 2% and 10% v/v.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102701288A (en) * | 2012-06-21 | 2012-10-03 | 北京工业大学 | Perovskite composite oxide LaFeO3 monodisperse micrometer hollow balls and preparation method thereof |
| CN106268296A (en) * | 2016-08-03 | 2017-01-04 | 中南大学 | A kind of flue gas processing method of the lanthanio perovskite composite oxide catalysis reduction simultaneous SO_2 and NO removal of doping |
| CN110465190A (en) * | 2019-08-13 | 2019-11-19 | 华北电力大学（保定） | A kind of photo-thermal coupling excitation H2O2Flue gas desulfurization and denitration method and product utilization |
| CN113262617A (en) * | 2021-06-09 | 2021-08-17 | 华中科技大学 | Desulfurization and denitrification system |
-
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102701288A (en) * | 2012-06-21 | 2012-10-03 | 北京工业大学 | Perovskite composite oxide LaFeO3 monodisperse micrometer hollow balls and preparation method thereof |
| CN106268296A (en) * | 2016-08-03 | 2017-01-04 | 中南大学 | A kind of flue gas processing method of the lanthanio perovskite composite oxide catalysis reduction simultaneous SO_2 and NO removal of doping |
| CN110465190A (en) * | 2019-08-13 | 2019-11-19 | 华北电力大学（保定） | A kind of photo-thermal coupling excitation H2O2Flue gas desulfurization and denitration method and product utilization |
| CN113262617A (en) * | 2021-06-09 | 2021-08-17 | 华中科技大学 | Desulfurization and denitrification system |
Non-Patent Citations (3)
| Title |
|---|
| Auto-combustion synthesis and characterization of perovskite-type LaFeO3 nanocrystals prepared via different routes;M.A. Gabal et al.;《Ceramics International》;第45卷;16530-16539 * |
| In Situ Modulation of A-Site Vacancies in LaMnO3.15 Perovskite for Surface Lattice Oxygen Activation and Boosted Redox Reactions;Xiaoqing Liu et al.;《Angew. Chem. Int. Ed.》;第60卷;Supporting Information第4页 * |
| Xiaoqing Liu et al..In Situ Modulation of A-Site Vacancies in LaMnO3.15 Perovskite for Surface Lattice Oxygen Activation and Boosted Redox Reactions.《Angew. Chem. Int. Ed.》.2021,第60卷Supporting Information第4页. * |
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