CN101304799A - 采用分级银/氧化铝催化剂系统来还原NOx排放物 - Google Patents
采用分级银/氧化铝催化剂系统来还原NOx排放物 Download PDFInfo
- Publication number
- CN101304799A CN101304799A CNA2006800352521A CN200680035252A CN101304799A CN 101304799 A CN101304799 A CN 101304799A CN A2006800352521 A CNA2006800352521 A CN A2006800352521A CN 200680035252 A CN200680035252 A CN 200680035252A CN 101304799 A CN101304799 A CN 101304799A
- Authority
- CN
- China
- Prior art keywords
- catalyst
- waste gas
- zeolite
- hydrocarbon
- tract
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 118
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 30
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 239000004332 silver Substances 0.000 title claims abstract description 22
- 230000009467 reduction Effects 0.000 title description 7
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 62
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract description 61
- 239000004215 Carbon black (E152) Substances 0.000 claims abstract description 57
- 238000006243 chemical reaction Methods 0.000 claims abstract description 31
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 27
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910021536 Zeolite Inorganic materials 0.000 claims abstract description 20
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000010457 zeolite Substances 0.000 claims abstract description 20
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 16
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 13
- 230000003647 oxidation Effects 0.000 claims abstract description 11
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 claims abstract description 6
- 230000002829 reductive effect Effects 0.000 claims description 32
- 239000002912 waste gas Substances 0.000 claims description 30
- 238000000034 method Methods 0.000 claims description 20
- 239000000463 material Substances 0.000 claims description 19
- 238000002485 combustion reaction Methods 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 12
- 239000002245 particle Substances 0.000 claims description 11
- 238000000576 coating method Methods 0.000 claims description 9
- 239000011248 coating agent Substances 0.000 claims description 8
- 230000003197 catalytic effect Effects 0.000 claims description 5
- 239000003380 propellant Substances 0.000 claims description 5
- 229910052783 alkali metal Inorganic materials 0.000 claims description 4
- 150000001340 alkali metals Chemical class 0.000 claims description 4
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims description 3
- 150000001342 alkaline earth metals Chemical class 0.000 claims description 3
- 229910052788 barium Inorganic materials 0.000 claims description 3
- 238000011144 upstream manufacturing Methods 0.000 claims description 3
- 239000000919 ceramic Substances 0.000 claims 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical group C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical group [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims 2
- 229910052708 sodium Inorganic materials 0.000 claims 2
- 239000011734 sodium Substances 0.000 claims 2
- 238000010531 catalytic reduction reaction Methods 0.000 abstract description 7
- 239000000470 constituent Substances 0.000 abstract description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 191
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical class CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 39
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 description 18
- 239000007789 gas Substances 0.000 description 18
- 229910052760 oxygen Inorganic materials 0.000 description 17
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 14
- 239000001301 oxygen Substances 0.000 description 14
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 13
- 238000004519 manufacturing process Methods 0.000 description 11
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 8
- 238000002360 preparation method Methods 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 8
- 150000001299 aldehydes Chemical class 0.000 description 7
- 239000010949 copper Substances 0.000 description 7
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 description 7
- 239000000126 substance Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000004088 simulation Methods 0.000 description 6
- 239000000654 additive Substances 0.000 description 5
- 230000000996 additive effect Effects 0.000 description 5
- 239000011449 brick Substances 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 229910021529 ammonia Inorganic materials 0.000 description 4
- 238000001354 calcination Methods 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 238000005342 ion exchange Methods 0.000 description 4
- 230000007246 mechanism Effects 0.000 description 4
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen(.) Chemical compound [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- 229910010413 TiO 2 Inorganic materials 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 239000006069 physical mixture Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 239000003708 ampul Substances 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 230000002860 competitive effect Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 238000004817 gas chromatography Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- -1 olefin hydrocarbon Chemical class 0.000 description 2
- 238000006213 oxygenation reaction Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- 230000001603 reducing effect Effects 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- XARVANDLQOZMMJ-CHHVJCJISA-N 2-[(z)-[1-(2-amino-1,3-thiazol-4-yl)-2-oxo-2-(2-oxoethylamino)ethylidene]amino]oxy-2-methylpropanoic acid Chemical compound OC(=O)C(C)(C)O\N=C(/C(=O)NCC=O)C1=CSC(N)=N1 XARVANDLQOZMMJ-CHHVJCJISA-N 0.000 description 1
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 1
- 101710134784 Agnoprotein Proteins 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 241001012508 Carpiodes cyprinus Species 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 206010013786 Dry skin Diseases 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910002089 NOx Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 150000001768 cations Chemical group 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052878 cordierite Inorganic materials 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 230000004992 fission Effects 0.000 description 1
- 239000002816 fuel additive Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 238000005213 imbibition Methods 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009616 inductively coupled plasma Methods 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 239000013067 intermediate product Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000001577 simple distillation Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- 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
- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
- B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
- B01D53/9404—Removing only nitrogen compounds
- B01D53/9409—Nitrogen oxides
- B01D53/9413—Processes characterised by a specific catalyst
- B01D53/9418—Processes characterised by a specific catalyst for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas
-
- 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
-
- 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
- B01D2251/2062—Ammonia
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2251/00—Reactants
- B01D2251/20—Reductants
- B01D2251/208—Hydrocarbons
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/10—Noble metals or compounds thereof
- B01D2255/104—Silver
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/204—Alkaline earth metals
- B01D2255/2042—Barium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/206—Rare earth metals
- B01D2255/2061—Yttrium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/207—Transition metals
- B01D2255/20761—Copper
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/50—Zeolites
-
- 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
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/48—Silver or gold
- B01J23/50—Silver
-
- 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
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/08—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the faujasite type, e.g. type X or Y
- B01J29/084—Y-type faujasite
-
- 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
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
-
- 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
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Combustion & Propulsion (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
通过将废气通过包含将NO氧化为NO2和将添加的烃部分氧化成醛的第一级氧化铝载银催化剂的分级催化剂床层,有助于稀燃发动机废气中的NOx成分的烃辅助选择性催化还原。银催化剂下游是第二催化剂,其被选择用于将烃和醛类与NO2还原反应成氮气。γ-氧化铝和BaY沸石都是适合作为第二级催化剂的例子。
Description
技术领域
本申请涉及来自稀燃汽油和柴油发动机的废气的处理,其中将NOx转化为氮气。更具体的,本发明涉及使用多级催化反应器烃辅助选择性催化还原富氧废气中的氮氧化物,多级催化反应器包含氧化铝载银催化剂作为用于转化NO为NO2以及部分氧化烃类的第一级,和用于将NO2转化为氮气的第二级催化剂。
背景技术
稀燃(lean-burn)汽油和柴油发动机是在高于化学计量比的空气/燃料(A/F)质量比下运行,用于节约燃料。与化学计量比的汽油发动机相比,它们还提供了好的驾驶性能并减少二氧化碳的排放。这样的稀燃发动机产生的热废气中含有相对高浓度的氧气和氮氧化物(NOx)。来自于已经预热后的柴油发动机的废气温度通常是200℃至400℃,并具有如下的典型组成:以体积计,约10-17%的氧气,3%的二氧化碳,0.1%的一氧化碳,180ppm的烃,235ppm的NOx和余量的氮气和水。由于在热废物流中存在高含量的氧气(O2)和水,使得这些通常包含一氧化氮(NO)和二氧化氮(NO2)的NOx气体难于被还原成氮气(N2)。
传统的采用化学计量比汽油发动机的三元催化剂不能非常有效地处理稀燃废气。研究者试图找到能够使用发动机出口的烃来选择性还原NOx(HC-SCR)(而不管与废气中氧含量的竞争性燃烧反应)的耐用催化剂。因为其低活性,窄的操作温度窗口以及候选催化剂材料不够耐久,使得这样的催化剂开发并不成功。
用于稀燃汽油或柴油发动机的NOx排放控制的技术之一是采用选择的燃料成分烃加入到废气物流中来还原NOx。提供该烃以产生用于将氮氧化物还原为氮的化学组分。在这种烃辅助SCR中,乙醇被认为是具有类似烃的还原剂效用,因为它能够在废气中转化成在还原NOx中有用的化学组分。乙醇可以作为燃料添加剂提供,以及如果需要的话,乙醇可以从燃料简单蒸馏出并储存在车辆的独立储罐中。
在一个由本发明的受让人开发的HC-SCR的改进中,环境空气通过一个低温等离子发生器以产生臭氧,并将臭氧引入到废气物流之中用于将NO氧化成为更容易转化成N2的NO2。在废气中,臭氧和氧气一起促进烃有限制地氧化成醛和醇,优选转化为包含多于两个碳原子的化合物。在等离子辅助的HC-SCR系统中,部分氧化的HC例如醛和醇(>C2),在通过由BaY沸石(上游床层)和CuY沸石(下游床层)催化剂组成的双床层上,能非常有效的还原NOx。然而只有采用大体积的此类催化剂才能获得高NOx转化效率,其导致了封装问题和预热缓慢。
由银微粒分散在高表面积γ-氧化铝颗粒(Ag/Al2O3)上组成的催化剂,在采用各种烃组分,例如发动机出口HC,部分氧化的HC和燃料成分的HC,来还原NOx的方面显示出适中的效果。对于较低成本的工艺,优选使用非贵金属催化剂用于NOx转化。此外,Ag/Al2O3能在比碱金属阳离子交换的沸石催化剂更高的空速下还原NOx。然而,单独使用银催化剂不足以将全部的NO转化为N2,并且在废气中会产生不期望的副产物。
因此,本发明的目的在于提供一种改进的方法,在该方法中使这种富氧和含氮氧化物的废气混合物中进行烃辅助选择性催化还原。本发明的更具体的目的在于提供一种在进行HC-SCR中使用银催化剂的改进方法。
发明概述
稀燃发动机废气包含如上所述的气体成分,还有含碳和不完全燃烧的烃的微粒物质。废气可以通过合适的过滤器或氧化反应器,在进行选择性催化还原NOx组分之前,来降低颗粒和不完全燃烧的气态烃含量。
在烃辅助选择性催化还原稀燃发动机废气中的NO和NO2时,向废气中加入合适的燃料成分的烃,以提供用于还原NOx成分的组分。例如烃辅助物质可以是汽油馏分或低分子量的柴油馏分,和/或氧化的烃如C1至C3的醇,如乙醇。烃按照废气中氮的含量成比例加入。通常,在较高氧含量和和较高废气或催化剂温度下,需要更高的烃量。
温度可能根据发动机运行在很广的范围内变化的废气然后穿过并接触选择性还原催化剂材料。催化剂通常用作涂层(washcoat),涂覆于一个或多个陶瓷(例如堇青石)整料石砖的蜂窝壁。废气通过整料蜂窝的空速通常在约25Kh-1至约50K h-1的范围内。
竞争性氧化反应和还原反应可能同时在气相中和催化剂颗粒上发生。烃裂变成更小的烷烃或烯烃分子,并部分氧化成醇和醛。NO氧化成NO2,以及NO和NO2都希望被还原成氮气。也可能形成一些含氧和含氮的碳化合物。
包含分散在高表面积较大颗粒上的细颗粒银,γ-氧化铝(Ag/Al2O3)的催化剂,即使是在相对低的废气温度下裂解烃作为还原组分并用于转化NO为NO2和N2,也是有效的。但是银催化剂的最佳用法是和下游的二级催化剂联合使用,以促进将NOx成分选择性催化还原为氮气。
例如基于氧化铝或BaY沸石之类的第二级催化剂位于Ag催化剂的下游,以促进NO2和部分氧化的烃(如醛)的反应。该下游催化剂床层可以由适合促进NOx和碳以及含氧还原物质反应的材料制成。
当废气以相对高的空速接触Ag催化剂床层时,NO和烃或C2+醇会快速转化成NO2和醛。废气接着流入并接触第二级床层,例如包含氧化铝或合适的金属阳离子交换过的Y沸石的第二级床层,在这里完成NO2被醛还原成N2。
如果在双层床反应器中形成了显著量的氨或其它含氮类物质,没有在还原NO2时被消耗,则可以使用用于NH3还原NOx的已知催化剂(例如铜交换ZSM沸石或Cu/TiO2)的第三级催化剂床层。
因此,本发明所述的分级烃辅助选择性催化还原系统包括:银催化剂的第一级床层(例如位于第一整料壁上的涂层),包含使用醛还原NO2为氮气的催化剂的第二级床层(例如位于下游的第二整料壁上的涂层),以及可选地包含使用氨还原NO2的催化剂的第三级床层。这种低成本分级反应器系统在宽废气温度范围内,能有效地获得NOx成分转化为氮气的高转化率。
本发明的其它目的和优点将通过如下优选的实施方案的具体描述来展现。
附图简述
附图1是当初始含有NO和乙醇添加剂的模拟稀燃发动机废气物流,以100kh-1的空速和在225℃至350℃范围内增加的相对低的催化剂温度下,通过分级Ag/Al2O3催化剂床结构时,来自NO和NO2的N2生成率(%)的图表。
附图2是当初始含有NO和正辛烷添加剂的模拟稀燃发动机废气物流,以100k h-1的空速和在225℃至350℃范围内增加的相对低的催化剂温度下,通过分级Ag/Al2O3催化剂床结构时,来自NO和NO2的N2生成率(%)的图表。
附图3是当初始含有NO和正辛烷添加剂的模拟稀燃发动机废气物流,以100k h-1的空速和在325℃至475℃范围内增加的催化剂温度下,通过分级Ag/Al2O3+BaY催化剂床结构,相对于其物理混合物,来自NO和NO2的N2生成率(%)的图表。
优选实施方案的描述
制备银催化剂和示例的第二级催化剂,用于在模拟来自稀燃发动机废气组合物的选择性催化还原中的使用和测试。在本发明优选实施方式中,使用银催化剂作为第一级催化剂和γ-氧化铝催化剂或BaY沸石催化剂作为第二级催化剂的双层床催化反应器。这些实施例中所用的催化剂的制备如下。
催化剂制备及表征
在商用γ-Al2O3粉体(Sasol,Catalox SBa-200,表面积=200m2/g)上,采用AgNO3(JT Baker)作为前驱体,采用初湿含浸法制备含有1.0和2.0wt%的Ag的Ag/Al2O3。催化剂在110℃下干燥一整夜,然后于500℃煅烧4h。Sasol公司的γ-Al2O3粉体含98+%的Al2O3和低含量的杂质(例如Na2O、TiO2和SiO2),并且在使用之前于550℃煅烧4h。
含Ba 17.0wt%的BaY由NaY挤出物(Zeolyst,CBV-100,10wt%Na,Si/Al=5.1),在室温下用Ba(NO3)2(JT Baker)作为前驱体,通过离子交换24小时制得。样品然后在120℃干燥4小时,并于550℃煅烧4小时。将离子交换和煅烧步骤重复四次。
含Cu 2.6wt%的Cu-ZSM-5通过NH4-ZSM-5粉体(Tosoh,HSZ-830A,Si/Al=14),在室温下用Cu(NO3)2(Aldrich)作为前驱体,通过同样的离子交换方法,离子交换24小时制得。样品然后在110℃干燥一整夜,并于450℃煅烧4小时。
Ag,Ba和Cu的浓度通过电感耦合等离子体原子发射光谱仪测量得到。
催化剂评价
如下全部实验均是在一个垂直的微反应器系统中进行,其中气体向下通过。60-80目的催化剂样品装在一个外径为3/8”的石英管中,然后装入电炉中。反应温度通过位于略高于催化剂床层的入口处的热电偶测得。除另行规定外,采用包含500ppm NO,15%O2,10%H2O以及余量的He的进料气体测量活性。烃还原剂采用~1200ppm的C2H5OH或~400ppm的n-C8H18。对乙醇而言计算出的C1/N比为4.8,对正辛烷为6.4。纯水和液态烃采用同样的方法,用独立的注射泵和吸液芯注入。注入的液体然后汽化并沿着气体管线加热到120℃以上。总气体流量固定在272ml/min(STP),通过使用不同的催化剂用量来改变气时空速。系统内部的压力控制在940torr,全部气流被导向分析仪器。必要的时候,反应物和产物的浓度通过Nicolet Nexus 670红外光谱(FT-IR)和带有Agilent 5973质谱仪的Agilen 6890气相色谱(GC-MS)测得。
通过烃(HC)转化率、NOx转化率、NO氧化率和N2生成率来评价催化剂的活性。烃(HC)转化率和NOx转化率基于它们通过催化剂前后的浓度差计算。另一方面,NO氧化率定义为NO转化为NO2的转化率,于此同时N2的生成率定义为NOx仅转化为N2的转化率。
%HC转化率=[HC(入口)-HC(出口)]/HC(入口)×100
%N2生成率=[N2(出口)×2]/[NO(入口)+NO2(入口)]×100
Ag/Al2O3样品作为NOx还原催化剂在模拟稀燃废气混合物中测试。如上所述的模拟进料气体物流由500ppm NO,15%O2,10%H2O以及剩余量的He组成。烃还原剂采用~1200ppm的C2H5OH或~400ppm的n-C8H18。发现即使是在低废气温度下银催化剂也很好地促进了NO氧化成NO2,以及乙醇和正辛烷氧化成乙醛。根据本发明,通过NO2与醛和烃反应来促进NO2还原成N2的催化剂与银催化剂一起使用并评价。进行测试来评价其中在第一催化剂床中使用Ag/Al2O3和在下游的第二催化剂床中使用氧化铝或BaY沸石催化剂的分级催化还原反应器针对NOx的性能。
实施例1
制备采用相同含量的Ag和Al2O3或BaY的三种不同催化剂配置:(A)0.12g 1wt%Ag/Al2O3;(B)先0.06g 2wt%Ag/Al2O3,接着0.06g Al2O3;(C)先0.06g 2wt%Ag/Al2O3,接着0.048g BaY。选择催化剂的总量使得每个催化剂床(在本例中即装有催化剂粉体的石英管)的空速为100kh-1。在这些第一系列的实验中,1200ppm乙醇加入到气流(500ppm NO,15%O2,10%H2O,He)中作为“烃”添加剂。催化剂的测试的温度配置分别是275℃、300℃、325℃和350℃。
在100k h-1条件下,NO被乙醇还原过程中,三种不同的配置均能获得类似的%乙醇转化率。尽管Ag的含量在三种配置中都是相同的,由于Ag颗粒聚集在催化剂床的前部,分层的催化剂构型(即配置B和C)的乙醇转化率启动(lightoft)稍快。如图1所示,在包括Al2O3和BaY作为可选的第二级催化剂的分层构型中,N2生成率显著增加。在全部温度范围内,分级催化剂的NOx还原性能改善两倍。另一方面,单独使用银催化剂只能促进约40%的NO和NO2转化。
副产物例如氨,乙醛和氰化氢可以在催化剂上形成,并能在催化反应器出口处检测到。使用银催化剂或银和氧化铝或BaY之一联合使用时,氨、乙醛和氰化氢的产物分布有相当大的差别。HCN随分级催化剂上的温度增加更容易消失。且在配置B中产生更多NH3。在高温度下(425℃至500℃),不管怎样的催化剂配置均能获得基本相同的N2生成率,这可能是因为:随着温度的增加,仅有催化剂床层的前部(Ag/Al2O3)被使用了。
实施例2
采用如下催化剂通过向废气中添加正辛烷来还原NO:(A)0.06g 2wt%Ag/Al2O3(200k h-1);(B)先0.06g 2wt%Ag/Al2O3,接着0.06gAl2O3(100k h-1);(C)先0.06g2wt%Ag/Al2O3(100k h-1),接着0.048gBaY。当单独使用银催化剂时(A)时,采用更高的空速(即200k h-1),这是由于采用1wt%的Ag的催化剂对于正辛烷的启动温度太低而不能与分级催化剂(B)和(C)进行公平的比较。
由于催化剂的前部Ag的量相同,正辛烷转化反应在催化剂A和B上以类似的温度启动。然而,如图2所示,当添加Al2O3置于Ag催化剂下游时(即,配置B),%N2生成率显著改善。有趣的是,添加Al2O3后既没有发现NH3也没有发现HCN。另外一方面,配置C在温度低于400℃时,启动温度降低了约50℃并且获得了更高的NOx还原水平。通过BaY改进NOx的还原性能可以通过如下事实来解释:BaY本身在更低温度下也能还原NOx;即BaY确实起到了比双功能机理提出的第二级催化剂更多的作用。
实施例3
Ag/Al2O3+变化的Al2O3用量
期望找到Ag/Al2O3和第二级催化剂的用量的最适宜的比例。于是在保持2wt%Ag/Al2O3用量固定在0.06g(即200 kh-1),使用两个不同Al2O3用量(0.06g和1.5×0.06g)来检查Al2O3用量的效果。在使用乙醇还原NO时,增加Al2O3用量,仅仅在275-350℃时NOx转化率和N2生成率稍有增加;在425-500℃下仍是相同水平的转化率。采用正辛烷还原NO,实际上所有温度下均得到相同水平的转化率,显示出在分层构型中使用额外Al2O3的回报递减。
实施例4
Ag/Al2O3+变化的BaY用量
在保持2wt%Ag/Al2O3用量固定在0.06g(即200k h-1),通过使用三个不同BaY用量(0.048g,0.7×0.048g和1.5×0.048g),测量BaY用量的效果。在使用乙醇还原NO时,通过增加BaY的用量,在更低温下乙醇和NOx会产生更高转化率,同时更高温下NOx转化率降低。有趣的是,随着BaY的用量增加,在更多的乙醛被消耗的同时,产生了更多的NH3;例如在350℃和1.5×200k h-1条件下,产生115ppm NH3和0ppm乙醛。即BaY会消耗乙醛而产生NH3,它能够通过NH3抑制NOx的还原。这提供了另外一种在更低温下改进NOx还原性能的机会——通过在BaY下游装入NH3-SCR催化剂(例如Cu/ZSM-5)。然而在使用正辛烷还原NO时,在所有的温度下均只有非常少量的NH3生成。
实施例5
混合催化剂和分级催化剂的比较
制备0.06g 2wt%的Ag/Al2O3和0.048g BaY的物理混合物(即均为200k h-1),用于比较上游-下游分级安排的两种同样的催化剂。分别采用正辛烷还原NO进行这两种催化剂安排的测试。混合物和分级安排的比较数据如图3所示。在所有温度范围内,物理混合物上的NOx的还原反应在被极大抑制。这可以归结于在催化剂床前部产生的与氧结合的烃类通过催化剂床后部中的Ag颗粒进行的燃烧反应。混合物可以认为是添加BaY改性的Ag/Al2O3的情况,因此,这显示出了使用这一分级系统相对于使用添加剂在提高Ag/Al2O3的NOx还原性能方面的优势。
多级SCR催化剂系统
由于温度升高而产生的更多的NH3,可以通过添加NH3-SCR催化剂对两级Ag催化剂系统进行扩展。事实上,在采用乙醇还原NOx过程中,发现NH3、CH3CN、HCN、CO以及CH3CHO形成时,就制备三组分复合催化剂——Ag/Al2O3+CuSO4/TiO4+Pt/TiO2以除去不期望的有害副产物。尽管这种尝试确实除去了这些副产物,但它却没有提高N2的生成率。这可能是因为在中心部的Cu催化剂上通过NH3还原NO由于乙醛而中毒;和/或是因为有用的与氧结合的烃类在位于下游的Ag催化剂上燃烧而浪费了。然而,因为乙醛被除去,并且在BaY和Al2O3作用下产生更多的NH3,所以通过在本研究中讨论的分层催化剂构型之后,增加NH3-SCR催化剂预计增加N2生成。
作为对上述实施例的说明,分别通过乙醇和正辛烷作为代表性烃还原剂研究用烃在Ag/Al2O3上还原NOx的反应机理。本研究获得的结果显示:烃的部分氧化和NO的氧化是在采用烃在Ag/Al2O3上还原NOx反应中的初始反应步骤。随着温度的升高,乙醇同样能在气相中转化为乙醛(不存在催化剂情况下)。正辛烷开始分裂并氧化成各种更小的烃,包括与氧结合的烃类。这种烃的氧化反应在Ag/Al2O3催化剂床的前部能更有效地发生,其中即使在类似烃和H2的还原剂存在下,NO也能有效地氧化成NO2。但是,从这些更有活性的反应物质形成N2则可能是发生在主体催化剂材料剩下的部分,可能是在Al2O3位点上。
这些发现和通过在Ag/Al2O3催化剂下游放置不同量的Al2O3的额外实验表明:在Ag/Al2O3上采用烃还原NO可能是通过双功能反应机理而发生的:NO和烃在Ag活性位上分别转化成NO2和更活泼的烃类(即更小的烯烃,与氧结合的烃);而N2则是通过这些中间产物,在包括Al2O3的不同活性位上的随后的反应中产生。
上述实施例的证据表明,通过分别优化各个反应步骤,所提出的双功能反应机理提供了改进Ag/Al2O3上还原NOx的总体性能的机会。将Al2O3或BaY置于Ag催化剂之后的分级催化剂系统的构思已经论证了:在较低温下,它能够改进采用乙醇和正辛烷来还原NOx为N2的反应。可以使用其它的第二级或下游催化剂。例如,其它碱土金属阳离子交换的Y沸石是适用的。或者碱金属阳离子交换的Y沸石,如Na-、K-、Li-交换的Y沸石也是适用的。
实际上,银和其它的催化剂都是以涂覆在整料的蜂窝壁上的涂层形式来使用的。不同的催化剂制剂可以被涂覆在不同的整料砖上,并串联顺序排列使用(例如在涂覆Ag催化剂的砖之后是涂覆BaY催化剂的砖)。或者,不同催化剂制剂也可以是以不同层的形式涂覆在单独的整料砖上(例如BaY涂覆作为整料蜂窝壁的底层,Ag涂覆作为整料蜂窝壁上的顶层)。
本发明所述的分级的含银催化剂系统,在无论是否向稀燃发动机废气中添加等离子情况下的烃辅助选择性催化还原NOx中均非常有用。
因此,虽然以一些优选实施例的方式对本发明进行了阐释,但是可以理解的是这些实施例仅是解释而不是对本发明范围的限制。
Claims (12)
1、一种将稀燃发动机废气中NOx内容物转化为氮气的方法,其中废气中包含NO和NO2,该方法包括如下步骤:
向废气中加入燃料成分烃和/或C1至C3醇;以及将废气通过催化反应器,其包括主要由在氧化铝上负载Ag组成的催化剂上游段,和相邻但是分开的用于还原NO2为氮气的催化剂下游段。
2、如权利要求1所述的方法,其中下游段主要由氧化铝颗粒组成。
3、如权利要求1所述的方法,其中下游段主要由碱金属阳离子交换的Y沸石或碱土金属阳离子交换的Y沸石的颗粒组成。
4、如权利要求1所述的方法,其中下游段主要由钠交换的Y沸石或钡交换的Y沸石的颗粒组成。
5、如权利要求1所述的方法,其中废气的温度范围在200℃至500℃。
6、一种将稀燃发动机废气中NOx内容物转化为氮气的方法,其中废气包含NO和NO2,该方法包括如下步骤:
向废气中加入燃料成分烃和/或C1至C3的醇;将废气接触主要由在氧化铝上负载Ag组成的催化剂上游段,将NO氧化为NO2,并且将烃或醇氧化为部分氧化的物质;
以及随后,将废气接触相邻但是分开的催化剂下游段,用于将醛物质与NO2反应从而还原NO2为氮气。
7、如权利要求6所述的方法,其中下游段主要由氧化铝颗粒组成。
8、如权利要求6所述的方法,其中下游段主要由碱金属阳离子交换的Y沸石或碱土金属阳离子交换的Y沸石颗粒组成。
9、如权利要求6所述的方法,其中下游段主要由钠交换的Y沸石或钡交换的Y沸石颗粒组成。
10、如权利要求6所述的方法,其中废气的温度范围在200℃至500℃。
11、如权利要求6所述的方法,其中氧化铝载银催化剂是以涂覆于第一陶瓷整料的蜂窝壁的涂层形式,用于醛物质与NO2反应的催化剂是以涂覆于第二陶瓷整料的蜂窝壁的涂层形式。
12、如权利要求6所述的方法,其中用于醛物质与NO2反应的催化剂是以涂覆于陶瓷整料的蜂窝壁的第一涂层形式,氧化铝载银催化剂是以涂覆于第一涂层的上涂层形式。
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/198,092 US7396517B2 (en) | 2005-08-05 | 2005-08-05 | Reduction of NOx emissions using a staged silver/alumina catalyst system |
US11/198,092 | 2005-08-05 | ||
PCT/US2006/027998 WO2007018990A2 (en) | 2005-08-05 | 2006-07-19 | Reduction of nox emissions using a staged silver/alumina catalyst system |
Publications (2)
Publication Number | Publication Date |
---|---|
CN101304799A true CN101304799A (zh) | 2008-11-12 |
CN101304799B CN101304799B (zh) | 2013-09-25 |
Family
ID=37717773
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN2006800352521A Active CN101304799B (zh) | 2005-08-05 | 2006-07-19 | 采用分级银/氧化铝催化剂系统来还原NOx排放物 |
Country Status (5)
Country | Link |
---|---|
US (1) | US7396517B2 (zh) |
KR (1) | KR101011752B1 (zh) |
CN (1) | CN101304799B (zh) |
DE (1) | DE112006002071B4 (zh) |
WO (1) | WO2007018990A2 (zh) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108554425A (zh) * | 2017-12-29 | 2018-09-21 | 佛山科学技术学院 | 一种废气净化催化剂 |
Families Citing this family (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7488462B2 (en) * | 2005-04-26 | 2009-02-10 | The Ohio State University | Multi-stage catalyst systems and uses thereof |
GB0523135D0 (en) * | 2005-11-14 | 2005-12-21 | Johnson Matthey Plc | Reducing coking over Ag/A1203 HC-SCR catalyst |
US7939039B2 (en) * | 2007-09-11 | 2011-05-10 | GM Global Technology Operations LLC | Bimetallic catalyst for NOx reduction in engine exhaust |
US8871669B2 (en) * | 2008-05-19 | 2014-10-28 | General Electric Company | Catalyst and method of manufacture |
US20100150801A1 (en) * | 2007-09-19 | 2010-06-17 | General Electric Company | FORMED CATALYST FOR NOx REDUCTION |
US20100143227A1 (en) * | 2008-12-05 | 2010-06-10 | General Electric Company | MIXED CATALYST FOR NOx REDUCTION AND METHODS OF MANUFACTURE THEREOF |
US8161731B2 (en) * | 2008-05-12 | 2012-04-24 | Caterpillar Inc. | Selective catalytic reduction using controlled catalytic deactivation |
US8245500B2 (en) * | 2008-07-07 | 2012-08-21 | Delphi Technologies, Inc. | Dual catalyst NOx reduction system for exhaust from lean burn internal combustion engines |
US20100115930A1 (en) * | 2008-11-07 | 2010-05-13 | Gm Global Technology Operations, Inc. | Exhaust after treatment system |
US20100196237A1 (en) * | 2009-01-30 | 2010-08-05 | General Electric Company | Templated catalyst composition and associated method |
US20100209329A1 (en) * | 2009-01-30 | 2010-08-19 | Basf Catalysts Llc | Catalyst for producing ammonia from hydrocarbon and nitrogen oxides |
US8178064B2 (en) * | 2009-05-11 | 2012-05-15 | Basf Corporation | Treatment of power utilities exhaust |
US8409515B2 (en) * | 2009-07-14 | 2013-04-02 | GM Global Technology Operations LLC | Exhaust gas treatment system |
US8783017B2 (en) | 2010-03-11 | 2014-07-22 | Cummins Inc. | System, method, and apparatus to engage alternate reductant in a NOx reduction system |
GB201111180D0 (en) * | 2011-05-20 | 2011-08-17 | Johnson Matthey Plc | System and method for generating NO2 |
GB201111553D0 (en) * | 2011-05-20 | 2011-08-24 | Johnson Matthey Plc | NOx reduction catalyst |
US8659415B2 (en) | 2011-07-15 | 2014-02-25 | General Electric Company | Alarm management |
US8751413B2 (en) | 2011-07-26 | 2014-06-10 | General Electric Company | Fuzzy logic based system monitoring system and method |
EP2822681A1 (en) | 2012-03-05 | 2015-01-14 | Basf Se | Ammonia oxidation reactor with internal filter element |
US8795621B2 (en) * | 2012-08-09 | 2014-08-05 | Exxonmobil Research And Engineering | Catalytic reduction of NOx with high activity catalysts with acetaldehyde reductant |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5850777B2 (ja) * | 1975-03-28 | 1983-11-12 | トウアネンリヨウコウギヨウ カブシキガイシヤ | チツソサンカブツノカンゲンヨウシヨクバイ |
FR2649622B1 (fr) * | 1989-07-12 | 1993-12-24 | Paroisse Ste Chimique Grande | Composition catalytique a base de zeolithe y, utilisable dans le traitement d'effluents oxygenes contenant des nox, sa preparation et son application |
JP3506292B2 (ja) * | 1995-10-09 | 2004-03-15 | 株式会社新エィシーイー | 自動車排気浄化方法 |
GB0020287D0 (en) * | 2000-08-17 | 2000-10-04 | Aea Technology Plc | The catalytic treatment of gases |
US6808694B2 (en) * | 2001-09-21 | 2004-10-26 | Battelle Memorial Institute | NOx reduction methods and apparatuses |
US7000382B2 (en) * | 2003-07-02 | 2006-02-21 | General Motors Corporation | Partial oxidation of alcohols |
US20060112678A1 (en) * | 2004-11-04 | 2006-06-01 | Eaton Corporation | Multiple reactant multiple catalyst selective catalytic reduction for NOx abatement in internal combustion engines |
-
2005
- 2005-08-05 US US11/198,092 patent/US7396517B2/en active Active
-
2006
- 2006-07-19 KR KR1020087005489A patent/KR101011752B1/ko not_active IP Right Cessation
- 2006-07-19 CN CN2006800352521A patent/CN101304799B/zh active Active
- 2006-07-19 DE DE112006002071T patent/DE112006002071B4/de active Active
- 2006-07-19 WO PCT/US2006/027998 patent/WO2007018990A2/en active Application Filing
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108554425A (zh) * | 2017-12-29 | 2018-09-21 | 佛山科学技术学院 | 一种废气净化催化剂 |
Also Published As
Publication number | Publication date |
---|---|
DE112006002071B4 (de) | 2013-01-03 |
KR20080042868A (ko) | 2008-05-15 |
WO2007018990A3 (en) | 2007-10-18 |
CN101304799B (zh) | 2013-09-25 |
US7396517B2 (en) | 2008-07-08 |
DE112006002071T5 (de) | 2008-05-29 |
KR101011752B1 (ko) | 2011-02-08 |
US20070031310A1 (en) | 2007-02-08 |
WO2007018990A2 (en) | 2007-02-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN101304799B (zh) | 采用分级银/氧化铝催化剂系统来还原NOx排放物 | |
CN101259377B (zh) | 使用燃料碳氢化合物作为还原剂的NOx还原的复合催化剂 | |
CN100467837C (zh) | 通过分级式催化剂还原NOx排放 | |
Abu-Jrai et al. | The influence of H2 and CO on diesel engine combustion characteristics, exhaust gas emissions, and after treatment selective catalytic NOx reduction | |
US10322403B2 (en) | Coating for reducing nitrogen oxides | |
RU2614411C2 (ru) | Цеолитный катализатор, содержащий металл | |
Sitshebo et al. | Promoting hydrocarbon-SCR of NOx in diesel engine exhaust by hydrogen and fuel reforming | |
Zheng et al. | LNT–SCR dual-layer catalysts optimized for lean NOx reduction by H2 and CO | |
CN101605968A (zh) | 具有氨阻滞作用的催化活化的柴油机粒子过滤器 | |
EP2637769B1 (en) | Exhaust gas nox treatment using three scr catalyst zones in series | |
CN101737134A (zh) | 贫燃发动机排气中的NOx还原用双床催化剂系统 | |
CN108295893A (zh) | 低磷菱沸石 | |
Sitshebo et al. | Improving the low temperature NOx reduction activity over a Ag-Al2O3 catalyst | |
EP1948351A1 (en) | Reducing coking over ag/al203 hc-scr catalyst | |
Gunnarsson et al. | Combining HC-SCR over Ag/Al2O3 and hydrogen generation over Rh/CeO2-ZrO2 using biofuels: An integrated system approach for real applications | |
Park et al. | Effective parameters for DME steam reforming catalysts for the formation of H2 and CO | |
Abu-Jrai et al. | The effect of H2 and CO on the selective catalytic reduction of NOx under real diesel engine exhaust conditions over Pt/Al2O3 | |
Bensaid et al. | Appraisal of a De-NO x System Based on H2 for Light-Duty Diesel Engine Vehicles | |
Malamis et al. | Optimizing the lean hydrocarbon NOx trap: Sequential and dual-layer configurations | |
Sitshebo | HC-SCR of NO\(_x\) emissions over Ag-AL\(_2\) O\(_3\) catalysts using diesel fuel as a reductant | |
Meng et al. | Conversion of Exhaust Gases from Dual-Fuel (Natural Gas-Diesel) Engine under Ni-Co-Cu/ZSM-5 Catalysts | |
Schmieg et al. | Catalysts for lean-burn engine exhaust aftertreatment using hydrocarbon selective catalytic reduction | |
Keenan et al. | The Use of Ozone in Low Temperature Methane Control for Natural Gas Applications | |
Malamis | Characterization and Optimization of Multifunctional Automotive Catalysts | |
Hou | Development of Spatially-Resolved FTIR–Gas Concentration Measurements inside a Monolith-Supported Selective Catalytic Reduction Catalyst |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant |