JPH05317652A - Method for purifying exhaust gas - Google Patents
Method for purifying exhaust gasInfo
- Publication number
- JPH05317652A JPH05317652A JP4130904A JP13090492A JPH05317652A JP H05317652 A JPH05317652 A JP H05317652A JP 4130904 A JP4130904 A JP 4130904A JP 13090492 A JP13090492 A JP 13090492A JP H05317652 A JPH05317652 A JP H05317652A
- Authority
- JP
- Japan
- Prior art keywords
- exhaust gas
- catalyst
- purifying
- alkaline earth
- earth metal
- 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
- 238000000034 method Methods 0.000 title claims abstract description 18
- 239000003054 catalyst Substances 0.000 claims abstract description 58
- 239000007789 gas Substances 0.000 claims abstract description 58
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 55
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 23
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract description 23
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 21
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000001301 oxygen Substances 0.000 claims abstract description 14
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 14
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 76
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 19
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 19
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 claims description 10
- 239000011148 porous material Substances 0.000 claims 1
- 238000000746 purification Methods 0.000 abstract description 26
- 239000004215 Carbon black (E152) Substances 0.000 abstract description 19
- 229910052784 alkaline earth metal Inorganic materials 0.000 abstract description 11
- 150000001342 alkaline earth metals Chemical class 0.000 abstract description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 19
- 230000001603 reducing effect Effects 0.000 description 9
- 239000000446 fuel Substances 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 6
- 239000002002 slurry Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 229910052878 cordierite Inorganic materials 0.000 description 4
- 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 4
- 238000011156 evaluation Methods 0.000 description 4
- 238000010304 firing Methods 0.000 description 4
- 239000000395 magnesium oxide Substances 0.000 description 4
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 4
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 3
- ITHZDDVSAWDQPZ-UHFFFAOYSA-L barium acetate Chemical compound [Ba+2].CC([O-])=O.CC([O-])=O ITHZDDVSAWDQPZ-UHFFFAOYSA-L 0.000 description 3
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 3
- 239000011575 calcium Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 230000001052 transient effect Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- -1 barium (Ba) Chemical class 0.000 description 2
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 2
- 239000000292 calcium oxide Substances 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000011068 loading method Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 description 1
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910021193 La 2 O 3 Inorganic materials 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 150000001341 alkaline earth metal compounds Chemical class 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000006255 coating slurry Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000005574 cross-species transmission Effects 0.000 description 1
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- UEGPKNKPLBYCNK-UHFFFAOYSA-L magnesium acetate Chemical compound [Mg+2].CC([O-])=O.CC([O-])=O UEGPKNKPLBYCNK-UHFFFAOYSA-L 0.000 description 1
- 235000011285 magnesium acetate Nutrition 0.000 description 1
- 239000011654 magnesium acetate Substances 0.000 description 1
- 229940069446 magnesium acetate Drugs 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 150000003057 platinum Chemical class 0.000 description 1
- 150000003058 platinum compounds Chemical class 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
Classifications
-
- 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
- Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
Landscapes
- Catalysts (AREA)
- Exhaust Gas After Treatment (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は排気ガスの浄化方法に関
し、更に詳しくは、酸素過剰下の排気ガス、即ち排気ガ
ス中に含まれる一酸化炭素、水素及び炭化水素等の還元
性物質を完全に酸化させるのに必要な酸素量よりも過剰
な量の酸素が含まれている排気ガス中の窒素酸化物（NO
x)を効率よく浄化する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying exhaust gas, and more particularly to exhaust gas in the presence of excess oxygen, that is, reducing substances such as carbon monoxide, hydrogen and hydrocarbons contained in the exhaust gas. Nitrogen oxides (NO) in the exhaust gas containing oxygen in excess of that needed to oxidize
x) is related to a method for efficiently purifying.
【０００２】[0002]
【従来の技術】従来、自動車の排気ガス浄化用触媒とし
て排気ガス中の一酸化炭素（CO) 及び炭化水素（HC) の
酸化と、窒素酸化物(NOx) の還元とを同時に行なって排
気ガスを浄化する排気ガス浄化用三元触媒が数多く知ら
れている。このような触媒としては、例えばコージェラ
イトなどの耐火性担体にγ−アルミナスラリーを塗布、
焼成し、パラジウム、白金、ロジウムなどの貴金属を担
持させたものが典型的である。（例えば特公昭56-27295
号公報など参照）2. Description of the Related Art Conventionally, as a catalyst for purifying exhaust gas of an automobile, exhaust gas is produced by simultaneously oxidizing carbon monoxide (CO) and hydrocarbon (HC) in the exhaust gas and reducing nitrogen oxides (NOx). Many three-way catalysts for purifying exhaust gas are known. As such a catalyst, for example, γ-alumina slurry is applied to a refractory carrier such as cordierite,
It is typically fired to carry a noble metal such as palladium, platinum or rhodium. (For example, Japanese Patent Publication Sho 56-27295
(See gazette, etc.)
【０００３】ところで、前記排気ガス浄化用触媒の性能
はエンジンの設定空燃比によって大きく左右され、希薄
混合気、つまり空燃比の大きいリーン側では燃焼後の排
気ガス中の酸素量が多くなり、酸化作用が活発に、還元
作用が不活発になる。逆に、空燃比の小さいリッチ側で
は燃焼後の排気ガス中の酸素量が少なくなり、酸化作用
が不活発に、還元作用が活発になる。一方、近年、自動
車の低燃費化の要請に応えて通常走行時になるべく酸素
過剰の混合気で燃焼させるリーン側での運転が行なわれ
ており、リーン側でも十分にNOx を浄化できる触媒が望
まれていた。By the way, the performance of the exhaust gas purifying catalyst is largely influenced by the set air-fuel ratio of the engine, and on the lean side where the air-fuel ratio is lean, that is, on the lean side where the air-fuel ratio is large, the amount of oxygen in the exhaust gas after combustion increases and the oxidation The action becomes active, and the reducing action becomes inactive. On the other hand, on the rich side where the air-fuel ratio is small, the amount of oxygen in the exhaust gas after combustion becomes small, the oxidizing action becomes inactive, and the reducing action becomes active. On the other hand, in recent years, in response to the demand for low fuel consumption of automobiles, lean side operation is performed in which fuel is burned with an oxygen-rich mixture as much as possible during normal driving. Was there.
【０００４】かかる状況下に酸素過剰雰囲気下の自動車
排気ガス浄化用触媒として、一酸化炭素（CO) 及び炭化
水素（HC) の酸化と、窒素酸化物(NOx) の還元を同時に
行なう触媒が種々提案されている。このような触媒とし
て、例えばアルミナ担体に白金を担持したPt/Al2O3触媒
が提案されている（例えば1991年４月11日付日本工業新
聞参照）。しかしながら、この触媒は、酸素過剰雰囲気
下において実用上十分な浄化率を示す触媒とはいえなか
った。Under such circumstances, various catalysts for purifying automobile exhaust gas in an oxygen-rich atmosphere include a catalyst that simultaneously oxidizes carbon monoxide (CO) and hydrocarbons (HC) and reduces nitrogen oxides (NOx). Proposed. As such a catalyst, for example, a Pt / Al 2 O 3 catalyst in which platinum is supported on an alumina carrier has been proposed (see, for example, the Nihon Kogyo Shimbun on April 11, 1991). However, this catalyst could not be said to be a catalyst showing a practically sufficient purification rate in an oxygen excess atmosphere.
【０００５】一方、本出願人らは、先に、定常走行時及
び過渡状態時（市街地走行模擬状態）においてNOX 浄化
率を高めるべくアルミナ担体に白金及びLa2O3 を担持し
た触媒を提案した（特願平３−344781号明細書参照）。
しかしながら、この触媒は、高温で耐久処理すると浄化
率が低下し、必ずしも必要十分な浄化率は得られなかっ
た。On the other hand, the present applicants have previously proposed a catalyst in which platinum and La 2 O 3 are supported on an alumina carrier in order to increase the NO x purification rate during steady running and transient conditions (simulated urban driving condition). (See Japanese Patent Application No. 3-344781).
However, when this catalyst was subjected to a durable treatment at a high temperature, the purification rate was lowered, and the necessary and sufficient purification rate was not always obtained.
【０００６】[0006]
【発明が解決しようとする課題】自動車の走行中のエン
ジンから排出される排気ガス組成は、理論Ａ／Ｆ値近傍
からオーバーリーンのＡ／Ｆ値 (約23) までの範囲内で
頻繁に変化する。従って、本発明は、前記した従来技術
の問題点を排除し、上記した実際の自動車等の走行状態
(Ａ／Ｆ値の過渡の連続) において、排気ガス中のNOx
、CO及びHCを効率よく浄化することができる排気ガス
の浄化方法を提供することを目的とする。The composition of the exhaust gas emitted from the engine while the automobile is running frequently changes within the range from the theoretical A / F value to the over lean A / F value (about 23). To do. Therefore, the present invention eliminates the above-mentioned problems of the prior art, and the above-mentioned actual driving state of an automobile or the like.
NOx in exhaust gas at (continuous A / F value transient)
It is an object of the present invention to provide an exhaust gas purification method capable of efficiently purifying CO, HC and CO.
【０００７】[0007]
【課題を解決するための手段】本発明に従えば、酸素過
剰雰囲気下における排気ガス中の一酸化炭素（CO）、炭
化水素（HC) および窒素酸化物（NOX ) を同時に浄化す
る排気ガス浄化方法であって、酸素過剰の排気ガスを、
多孔質体からなる担体に、アルカリ土類金属酸化物およ
び白金（Pt）を担持してなる排気ガス浄化用触媒と接触
させることから成る排気ガスの浄化方法が提供される。According to the present invention, an exhaust gas for simultaneously purifying carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NO x ) in the exhaust gas in an oxygen excess atmosphere. It is a purification method, and exhaust gas with excess oxygen is
Provided is a method for purifying exhaust gas, which comprises bringing a carrier made of a porous body into contact with an exhaust gas purifying catalyst which carries an alkaline earth metal oxide and platinum (Pt).
【０００８】以下に説明するように、本発明の排気ガス
浄化方法によれば、希薄燃焼エンジンを搭載した車両か
ら排出される排気ガス中のCO、HC及びNOx を過渡状態
（市街地走行模擬状態）においても高効率で浄化するこ
とができる。As described below, according to the exhaust gas purification method of the present invention, CO, HC and NOx in the exhaust gas discharged from the vehicle equipped with the lean burn engine are in a transient state (simulated urban driving state). Even in the case, it can be purified with high efficiency.
【０００９】本発明の排気ガス浄化方法に用いる触媒は
活性金属として、白金（Pt) と、バリウム(Ba)、カルシ
ウム(Ca)、マグネシウム(Mg)、ストロンチウム(Sr)など
のアルカリ土類金属の酸化物を用い、これらを多孔質担
体に担持させて使用する。The catalyst used in the exhaust gas purifying method of the present invention comprises platinum (Pt) as an active metal and alkaline earth metals such as barium (Ba), calcium (Ca), magnesium (Mg) and strontium (Sr). An oxide is used, and these are supported on a porous carrier before use.
【００１０】本発明において用いることのできる多孔質
担体としては、アルミナ、ゼオライト、ジルコニア、シ
リカアルミナ、シリカ等をあげることができる。これら
の多孔質担体の種類及び物性については特に限定はな
く、従来から触媒用として使用されていた任意の多孔質
担体を使用することができる。また、これらの多孔質担
体はコージェライト、耐熱金属合金等からなるハニカム
基体にコートして用いても良い。Examples of the porous carrier that can be used in the present invention include alumina, zeolite, zirconia, silica-alumina, silica and the like. The type and physical properties of these porous carriers are not particularly limited, and any porous carrier conventionally used for catalysts can be used. Further, these porous carriers may be used by coating them on a honeycomb substrate made of cordierite, heat-resistant metal alloy or the like.
【００１１】本発明に係る排気ガス浄化用触媒は、前記
した多孔質担体に、白金とアルカリ土類金属酸化物を担
持してなる。これら金属の担持量には特に限定はない
が、アルカリ土類金属酸化物の担持量は、アルカリ土類
金属として0.05〜10.0 mol／リットルであることが好ま
しい。このアルカリ土類金属酸化物の担持量が 0.05mol
／リットル未満の場合、十分な NOx浄化率を得ることが
できない恐れがあり、また、10.0 mol／リットルを超え
ると担体の表面積を低下させる恐れがある。好ましく
は、0.15〜5.0mol／リットルである。The exhaust gas purifying catalyst according to the present invention comprises platinum and an alkaline earth metal oxide supported on the above-mentioned porous carrier. The supported amount of these metals is not particularly limited, but the supported amount of the alkaline earth metal oxide is preferably 0.05 to 10.0 mol / liter as the alkaline earth metal. The supported amount of this alkaline earth metal oxide is 0.05 mol.
If it is less than 1 / liter, a sufficient NOx purification rate may not be obtained, and if it exceeds 10.0 mol / liter, the surface area of the carrier may be reduced. It is preferably 0.15 to 5.0 mol / liter.
【００１２】本発明に係る排気ガス浄化用触媒における
白金の担持量にも特に限定はないが、 0.1〜10.0ｇ／リ
ットルであることが好ましい。この白金の担持量が 0.1
ｇ／リットル未満の場合には、十分な触媒活性が得られ
ない恐れがあり、また、10.0ｇ／リットルを超えると、
それ以上白金の担持量を増加させても白金の粒成長が促
進され、活性向上は僅かで高価となるのみである。特
に、白金の担持量が 0.5〜 3.0ｇ／リットルである場合
は、活性とコストの面で好ましい。The amount of platinum supported on the exhaust gas purifying catalyst according to the present invention is not particularly limited, but is preferably 0.1 to 10.0 g / liter. This platinum loading is 0.1
If it is less than g / liter, sufficient catalytic activity may not be obtained, and if it exceeds 10.0 g / liter,
Even if the amount of platinum supported is further increased, the grain growth of platinum is promoted, and the activity improvement is only slight and expensive. Particularly, when the amount of platinum supported is 0.5 to 3.0 g / liter, it is preferable in terms of activity and cost.
【００１３】本発明において使用する排気ガス浄化用触
媒の製造方法については、特に限定はなく、従来の一般
的方法に準ずることができる。例えば常法に従って調製
したアルミナを含有するスラリー中にコージェライトか
らなる基体を浸漬して表面にアルミナをコートし乾燥焼
成（例えば温度 600〜 700℃) 後、ジニトロジアミン白
金、塩化白金酸などの白金化合物の水溶液に浸漬し、乾
燥焼成（例えば温度 200〜 500℃) して多孔質担体に白
金を担持させ、更にアルカリ土類金属の酢酸塩などの水
溶性アルカリ土類金属化合物の水溶液に浸漬し、乾燥焼
成（例えば温度600〜 700℃) してアルカリ土類金属を
担持させて製造することができる。The method for producing the exhaust gas purifying catalyst used in the present invention is not particularly limited and can be based on the conventional general method. For example, a substrate made of cordierite is dipped in a slurry containing alumina prepared according to a conventional method, the surface is coated with alumina, and dried and baked (for example, at a temperature of 600 to 700 ° C). Immersion in an aqueous solution of the compound, dry firing (for example, at a temperature of 200 to 500 ° C.) to support platinum on the porous carrier, and further dipping in an aqueous solution of a water-soluble alkaline earth metal compound such as an alkaline earth metal acetate It can be manufactured by carrying out dry firing (for example, a temperature of 600 to 700 ° C.) and supporting an alkaline earth metal.
【００１４】また、別法として、アルミナとアルカリ土
類金属酸化物を含有するスラリー中に基体を浸漬してア
ルミナをコートし、乾燥焼成後、ジニトロジアミン白
金、塩化白金酸などの白金化合物の水溶液に浸漬し、乾
燥焼成し、アルカリ土類金属と白金を担持させて製造す
ることができる。なお、アルカリ土類金属は使用される
環境によって水酸化物などになる場合もある。As an alternative method, the substrate is dipped in a slurry containing alumina and an alkaline earth metal oxide to coat alumina, dried and baked, and then an aqueous solution of a platinum compound such as dinitrodiamine platinum or chloroplatinic acid. It can be manufactured by immersing it in, and drying and firing it to carry an alkaline earth metal and platinum. The alkaline earth metal may become a hydroxide or the like depending on the environment in which it is used.
【００１５】本発明に係る排気ガス浄化方法において排
気ガスを浄化するにあたっては、希薄燃焼エンジンの排
気通路において触媒を設置する場所には特に限定はない
が、例えば車両の床下、スタート触媒または三元触媒の
下流側の床下などに配置するのが好ましい。In purifying the exhaust gas in the exhaust gas purifying method according to the present invention, the place where the catalyst is installed in the exhaust passage of the lean burn engine is not particularly limited. For example, under the floor of the vehicle, start catalyst or three-way catalyst. It is preferably arranged under the floor on the downstream side of the catalyst.
【００１６】本発明に係る浄化方法は通常の方法で実施
することができ、排気ガスを触媒層に導入する空間速度
(SV)にも特に限定はなく、例えば 300,000〜10,000hr-1
の範囲が好ましく、また触媒層温度にも特に制限はない
が、 200〜 500℃程度の温度が好ましい。The purification method according to the present invention can be carried out by a usual method, and the space velocity for introducing the exhaust gas into the catalyst layer is
(SV) is not particularly limited, for example, 300,000 ~ 10,000hr -1
Is preferable, and the temperature of the catalyst layer is not particularly limited, but a temperature of about 200 to 500 ° C. is preferable.
【００１７】[0017]
【作用】本発明に従って、アルカリ土類金属酸化物と白
金とを多孔質担体に担持した触媒を用い、これを希薄燃
焼する内燃機関の排気通路に設置すると、以下の実施例
にも示すように、車両走行時に、CO、HC及びNOx を高効
率で浄化できる。本発明に係る排気ガスの浄化方法が優
れた効果を発揮するメカニズムについては、未だ必ずし
も明らかではないが、次のように考えられる。According to the present invention, when a catalyst in which an alkaline earth metal oxide and platinum are supported on a porous carrier is used and installed in the exhaust passage of an internal combustion engine which burns lean, as shown in the following examples. , CO, HC and NOx can be purified with high efficiency while the vehicle is running. The mechanism by which the method for purifying exhaust gas according to the present invention exerts excellent effects is not necessarily clear yet, but is considered as follows.
【００１８】本発明による触媒の構成は、例えばアルミ
ナなどの多孔質担体の表面に酸化バリウム(BaO) 、酸化
マグネシウム（MgO)、酸化カルシウム（CaO)などのアル
カリ土類金属の酸化物と白金が担持されており、かかる
構成の触媒は車両走行時のエンジン排出ガスの組成変化
に対して次のように作用するものと想定する。The catalyst according to the present invention is composed of, for example, an oxide of an alkaline earth metal such as barium oxide (BaO), magnesium oxide (MgO) and calcium oxide (CaO) and platinum on the surface of a porous carrier such as alumina. It is assumed that the catalyst thus supported acts on the composition change of the engine exhaust gas while the vehicle is running as follows.
【００１９】車両停止時：Ａ／Ｆは理論Ａ／Ｆ近傍で排
気ガス中には NOxが少ない。触媒上ではアルカリ土類金
属酸化物に吸着されていた NOxがPtに移動（逆スピルオ
ーバー）し、排気ガス中の還元ガス（CO、Ｈ2 、HC) と
反応し、NOx はＮ2 に還元され、この際、還元ガスも浄
化される。アルカリ土類金属酸化物に吸着された NOxが
無くなれば、Pt上に還元ガスが吸着される。When the vehicle is stopped: The A / F is near the theoretical A / F and the exhaust gas contains little NOx. NOx adsorbed on the alkaline earth metal oxide on the catalyst moves to Pt (reverse spillover) and reacts with the reducing gas (CO, H 2 , HC) in the exhaust gas, and NOx is reduced to N 2. At this time, the reducing gas is also purified. When NOx adsorbed on the alkaline earth metal oxide disappears, reducing gas is adsorbed on Pt.
【００２０】車両加速時：Ａ／Ｆは理論Ａ／Ｆ近傍から
リーン（Ａ／Ｆ＝23）まで連続的に変化し、排気ガス中
にNOX が多量に存在することになる。触媒上では排気ガ
ス中のNOX がPtに吸着した還元ガスによりＮ2 に還元さ
れ、この際、還元ガスも浄化される。During vehicle acceleration: A / F continuously changes from near the theoretical A / F to lean (A / F = 23), and a large amount of NO X exists in the exhaust gas. On the catalyst, NO X in the exhaust gas is reduced to N 2 by the reducing gas adsorbed on Pt, and at this time, the reducing gas is also purified.
【００２１】定常走行時：Ａ／Ｆはリーン（Ａ／Ｆ＝2
3）状態で、排気ガス中のNOX は加速時よりも少なく、H
Cは多めとなり、NOX はHCによりＮ2 に還元される。こ
の際、HCも浄化され、また、反応しないNOX は担体上の
アルカリ土類金属酸化物に吸着される。このリーン状態
におけるNOX の吸着量がランタン（La）より非常に大き
いため、本発明の浄化方法ではNOX 浄化能が高いものと
思われる。During steady running: A / F is lean (A / F = 2
In the 3) state, NO X in the exhaust gas is less than during acceleration and H
C is increased, and NO X is reduced to N 2 by HC. At this time, HC is also purified, and unreacted NO X is adsorbed by the alkaline earth metal oxide on the carrier. Since the adsorption amount of NO X in this lean state is much larger than that of lanthanum (La), it is considered that the purification method of the present invention has a high NO X purification capacity.
【００２２】減速時：Ａ／Ｆはオートマティック（Ａ／
Ｔ）車では理論Ａ／Ｆ近傍であり、マニュアル（Ｍ／
Ｔ）車では酸化雰囲気（燃料カット）となり、排気ガス
中のNO X は少ない。触媒上ではＡ／Ｔ車の場合は車両停
止時と同じ状態になり、Ｍ／Ｔ車の場合にはNOX はアル
カリ土類金属酸化物に吸着保持される。During deceleration: A / F is automatic (A / F
T) is near theoretical A / F, and manual (M /
T) Oxidizing atmosphere (fuel cut) in cars and exhaust gas
NO inside XIs few. A / T car stops on the catalyst
It will be in the same state as when stopped, NO for M / T carsXIs al
It is adsorbed and held by the potassium earth metal oxide.
【００２３】[0023]
【実施例】以下、実施例に従って、本発明を更に詳しく
説明するが、本発明の範囲をこれらの実施例に限定する
ものでないことはいうまでもない。以下の例において
「部」は特にことわらない限り「重量部」を示す。EXAMPLES The present invention will be described in more detail below with reference to Examples, but it goes without saying that the scope of the present invention is not limited to these Examples. In the following examples, "parts" means "parts by weight" unless otherwise specified.
【００２４】実施例１ 担持量の異なるPt／酸化バリウム／アルミナのハニカム
触媒を調製し、NOX 浄化活性を比較した。ａ） アルミナ・スラリーの調製 アルミナ粉末 100部に、アルミナゾル（アルミナ含有率
10重量％）70部、40重量％硝酸アルミニウム水溶液15部
および水30部を加えて攪拌混合し、コーティング用スラ
リーを調製した。 Example 1 Pt / barium oxide / alumina honeycomb catalysts having different loadings were prepared and their NO x purification activities were compared. a) Preparation of alumina slurry To 100 parts of alumina powder, alumina sol (alumina content rate)
10 parts by weight) 70 parts, 40 parts by weight aluminum nitrate aqueous solution 15 parts and water 30 parts were added and mixed with stirring to prepare a coating slurry.
【００２５】ｂ） コーティング及び焼成 コージェライト製ハニカム基体を水に浸漬し、余分な水
を吹き払った後、上記ａ）で得られたスラリーに浸漬
し、取り出した後、余分なスラリーを吹き払い、温度80
℃で20分間乾燥し、更にこれを 600℃で１時間焼成し
た。アルミナのコート量はハニカムの体積１リットル当
たり 120g であった。 B) Coating and firing A cordierite honeycomb substrate is dipped in water to blow off excess water, then dipped in the slurry obtained in the above a), taken out, and blown off the excess slurry. , Temperature 80
It was dried at ℃ for 20 minutes and then calcined at 600 ℃ for 1 hour. The coating amount of alumina was 120 g per liter of honeycomb volume.
【００２６】ｃ） Ｐｔの担持 上記のようにして得られたハニカム担体を、表１に示す
Pt担持量が得られるように調製した所定濃度のジニトロ
ジアミン白金の水溶液に浸漬し、 250℃で乾燥して表１
に示すPtの担持量を持つ触媒を調製した。 C) Support of Pt The honeycomb carrier obtained as described above is shown in Table 1.
It was immersed in an aqueous solution of dinitrodiamine platinum having a predetermined concentration prepared so that the amount of Pt supported was obtained, and dried at 250 ° C.
A catalyst having a supported amount of Pt shown in was prepared.
【００２７】ｄ）表１に示すBa担持量が得られるように
調製した所定濃度の酢酸バリウム水溶液に前記白金担持
担体を浸漬し、乾燥後、 600℃で１時間焼成し、表１の
触媒No.2〜13の本発明の触媒を得た。比較触媒としてN
o.1及び14〜17の触媒も上記実施例に準じた方法で併せ
調製した。D) The platinum-supported carrier was immersed in an aqueous solution of barium acetate having a predetermined concentration prepared so that the amount of supported Ba shown in Table 1 was obtained, dried, and calcined at 600 ° C. for 1 hour to prepare the catalyst No. .2 to 13 of the catalyst of the present invention was obtained. N as a comparative catalyst
The catalysts of o.1 and 14 to 17 were also prepared in the same manner as in the above example.
【００２８】 表１：調製触媒 ────────────────────────── 担持量 触媒No. Ba(mol/ リットル) Pt(g/リットル) １ ０．０３ ２．０ ２ ０．１５ ２．０ ３ ０．２ ２．０ ４ ０．３ ２．０ ５ ０．５ ２．０ ６ １．０ ２．０ ７ １０．０ ２．０ ８ ０．２ ０．５ ９ ０．２ １．０ １０ ０．２ ５．０ １１ ０．２ １０．０ １２ ０．０５ ２．０ １３ ０．１ ２．０ １４ ０ １．０ １５ ０ ２．０ １６ ０ １０．０ １７ １１．０ ２．０ ────────────────────────── （注）触媒２〜13 ： 実施例 触媒１及び14〜17 ： 比較例 Table 1: Preparation catalyst ────────────────────────── Supported amount catalyst No. Ba (mol / liter) Pt (g / liter ) 1 0.03 2.0 2 0.15 2.0 3 3 0.2 2.0 4 0.3 2.0 5 5 0.5 2.0 6 6 1.0 2.0 7 7 10.0 2.0 8 0.2 0.5 9 0.2 1.0 10 0.2 0.2 5.0 11 0.2 10.0 12 0.05 0.05 2.0 13 0.1 2.0 14 0 1.0 15 0 2 0.0 16 0 10.0 17 11.0 2.0 ────────────────────────── (Note) Catalysts 2 to 13: Examples Catalysts 1 and 14 to 17: Comparative example
【００２９】浄化性能の評価 上記触媒の浄化性能を下記条件で評価した。 エミッション評価 希薄燃焼エンジン（ 1.6リットル）搭載車両の排気通路
に上記触媒を設置し、市街地走行モードで走行して、C
O、HC及びNOx の浄化率を測定し、結果を表３に示す。
尚、耐久処理触媒とは、希薄燃焼エンジン（1.6 リット
ル）の排気通路に上記触媒を設置し、エンジンをＡ／Ｆ
＝18、入りガス温度 650℃で50時間運転したものであ
る。 Evaluation of Purification Performance The purification performance of the above catalyst was evaluated under the following conditions. Emission evaluation Install the above catalyst in the exhaust passage of a vehicle equipped with a lean-burn engine (1.6 liters), run in city driving mode,
The purification rates of O, HC and NO x were measured, and the results are shown in Table 3.
The endurance-treated catalyst is a lean-burn engine (1.6 liters) installed in the exhaust passage and the engine
= 18, the inlet gas temperature was 650 ° C, and it was operated for 50 hours.
【００３０】 表２：浄化性能の評価 ─────────────────────────────── 初期触媒の浄化率（％） 耐久処理触媒の浄化率（％） 触媒No. NOX HC CO NOX HC CO １ 42 96 100 24 89 94 ２ 92 95 100 42 88 97 ３ 92 96 100 47 89 96 ４ 93 95 100 50 88 98 ５ 93 93 100 52 86 98 ６ 93 90 100 53 83 97 ７ 74 93 99 30 84 95 ８ 88 94 100 39 82 94 ９ 90 97 100 44 86 97 １０ 93 98 100 47 94 99 １１ 93 98 100 48 95 99 １２ 66 96 100 28 90 96 １３ 90 96 100 30 89 93 １４ 38 97 100 12 88 91 １５ 46 98 100 18 90 92 １６ 49 98 100 21 93 96 １７ 52 89 97 18 87 91 ───────────────────────────── （注）触媒２〜13 ： 実施例 触媒１及び14〜17 ： 比較例 Table 2: Evaluation of purification performance ─────────────────────────────── Initial catalyst purification rate (%) Durability Purification rate of treated catalyst (%) Catalyst No. NO X HC CO NO X HC CO 1 42 96 100 24 89 94 2 92 95 100 42 88 97 3 92 96 100 47 89 96 4 93 95 100 50 88 98 5 93 93 100 52 86 98 6 93 90 100 53 83 97 7 74 93 99 30 84 95 8 88 94 100 39 82 94 9 90 97 100 44 86 97 10 93 98 100 47 94 99 11 93 98 100 48 95 99 12 66 96 100 28 90 96 13 90 96 100 30 89 93 14 38 97 100 12 88 91 15 46 98 100 18 90 92 16 16 98 98 100 21 93 96 17 52 89 97 18 87 91 ───────────── ───────────────── (Note) Catalysts 2 to 13: Examples Catalysts 1 and 14 to 17: Comparative examples
【００３１】上記結果から明らかなように、本発明によ
る排気ガス浄化方法によれば、希薄燃焼エンジンを搭載
した車両から排出される排気ガス中のNOx 、CO及びHCを
耐久処理後も劣化が少なく効率よく浄化することがで
き、特に、触媒中のアルカリ土類金属の担持量が0.15〜
1.0mol／リットルで、白金の担持量が 0.5〜 7.0g ／リ
ットルであるのが好ましい。As is clear from the above results, according to the exhaust gas purification method of the present invention, NO x , CO and HC in the exhaust gas discharged from the vehicle equipped with the lean burn engine are not deteriorated even after the endurance treatment. The amount of alkaline earth metal supported in the catalyst is 0.15 ~
It is preferable that the amount of platinum supported is 0.5 to 7.0 g / liter at 1.0 mol / liter.
【００３２】実施例２ 実施例１において、酢酸バリウムに代えて硝酸カルシウ
ム、また同様に酢酸バリウムに代えて酢酸マグネシウム
を用いた以外は実施例１と同様にして、表３に示すよう
に、担持量の異なるPt／酸化カルシウム／アルミナ、Pt
／酸化マグネシウム／アルミナ及びPt／酸化カルシウム
＋酸化マグネシウム／アルミナのハニカム触媒を各々調
製し、実施例１と同様に触媒の浄化活性を評価した。結
果を表４に示す。 Example 2 In the same manner as in Example 1 except that calcium nitrate was used in place of barium acetate and magnesium acetate was used in place of barium acetate in the same manner as in Example 1, as shown in Table 3, Different amounts of Pt / calcium oxide / alumina, Pt
/ Magnesium oxide / alumina and Pt / calcium oxide + magnesium oxide / alumina honeycomb catalysts were prepared, and the purification activity of the catalyst was evaluated in the same manner as in Example 1. The results are shown in Table 4.
【００３３】 表３：調製触媒 ─────────────────────────────── 担 持 量 触媒No. Ca(mol/リットル) Mg(mol/リットル) Pt(g/リットル) １８ 0.03 − 2.0 １９ 0.05 − 2.0 ２０ 0.1 − 2.0 ２１ 0.15 − 2.0 ２２ 0.2 − 2.0 ２３ 0.3 − 2.0 ２４ 0.5 − 2.0 ２５ 1.0 − 2.0 ２６ 10.0 − 2.0 ２７ 0.2 − 0.5 ２８ 0.2 − 1.0 ２９ 0.2 − 5.0 ３０ 0.2 − 10.0 ３１ 11.0 − 2.0 ３２ − 0.15 2.0 ３３ − 0.2 2.0 ３４ − 0.3 2.0 ３５ − 0.5 2.0 ３６ − 1.0 2.0 ３７ 0.1 0.1 2.0 ─────────────────────────────── Table 3: Preparation catalyst ─────────────────────────────── Supported catalyst No. Ca (mol / liter ) Mg (mol / liter) Pt (g / liter) 18 0.03 − 2.0 19 0.05 − 2.0 20 0.1 − 2.0 21 0.15 − 2.0 22 0.2 − 2.0 23 0.3 − 2.0 24 0.5 − 2.0 25 1.0 − 2.0 26 10.0 − 2.0 27 0.2 − 0.5 28 0.2 − 1.0 29 0.2 − 5.0 30 0.2 − 10.0 31 11.0 − 2.0 32 − 0.15 2.0 33 − 0.2 2.0 34 − 0.3 2.0 35 − 0.5 2.0 36 − 1.0 2.0 37 0.1 0.1 2.0 ──────── ────────────────────────
【００３４】 表４：浄化性能の評価 ─────────────────────────────── 初期触媒の浄化率（％） 耐久処理触媒の浄化率（％） 触媒No. NOX HC CO NOX HC CO １８ 38 95 100 23 87 96 １９ 72 96 100 25 87 95 ２０ 89 95 100 32 89 93 ２１ 90 94 100 46 88 98 ２２ 93 96 100 48 86 97 ２３ 92 96 100 48 89 98 ２４ 92 95 100 50 87 96 ２５ 94 95 100 52 84 97 ２６ 69 91 100 28 85 96 ２７ 89 93 100 41 82 93 ２８ 90 95 100 44 85 97 ２９ 92 98 100 46 92 99 ３０ 92 99 100 46 94 99 ３１ 54 90 96 15 83 95 ３２ 67 95 100 30 89 98 ３３ 67 97 100 35 89 98 ３４ 67 97 100 36 91 99 ３５ 68 95 100 36 90 99 ３６ 68 92 100 35 88 97 ３７ 91 95 100 47 89 97 ─────────────────────────────── Table 4: Evaluation of purification performance ─────────────────────────────── Initial catalyst purification rate (%) Durability Purification rate (%) of treated catalyst Catalyst No. NO X HC CO NO X HC CO 18 38 95 100 23 87 96 19 72 96 100 25 87 95 20 89 95 100 32 89 93 21 90 94 100 46 88 98 22 93 96 100 48 86 97 23 92 96 100 48 89 98 24 92 95 100 50 87 96 25 94 95 100 52 84 97 26 69 91 100 28 85 96 27 89 93 100 41 82 93 28 90 95 100 44 85 97 29 92 98 100 46 92 99 30 92 99 100 46 94 99 31 54 90 96 15 83 95 32 67 95 100 30 89 98 33 33 97 97 100 35 89 98 34 34 97 97 100 36 91 99 35 68 95 100 36 90 99 36 36 92 92 35 88 97 37 91 95 100 47 89 97 ───────────────────────────────
【００３５】[0035]
【発明の効果】自動車は、実際の運転において、加減速
を繰り返すのが実状であり、かかる状況下に排出される
排気ガスに対し、本発明によれば、Ptの電子状態をアル
カリ土類金属の酸化物によりコントロールすることによ
り、HCとNox との反応活性を向上させることができ、更
に、アルカリ土類金属の酸化物のNox 吸着特性を利用
し、加減速におけるNox 浄化率を大きく向上させること
ができる。この結果、酸素過剰の排気ガス中のCO及びHC
を十分に浄化したもとで、同排気ガス中の窒素酸化物を
効率よく浄化することができる。According to the present invention, according to the present invention, the Pt electronic state is changed to the alkaline earth metal, as compared with the exhaust gas discharged under such a circumstance. of by controlling the oxide, it is possible to improve the reactivity of HC and No x, further utilizing the No x adsorption properties of the oxides of alkaline earth metals, a No x purification rate of acceleration and deceleration It can be greatly improved. As a result, CO and HC in exhaust gas with excess oxygen
The nitrogen oxides in the exhaust gas can be efficiently purified under sufficient purification.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 金沢 孝明 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 谷澤 恒幸 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 水野 達司 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 井口 哲 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 加藤 健治 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 田中 俊明 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 竹島 伸一 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 木原 哲郎 愛知県豊田市トヨタ町１番地 トヨタ自動 車株式会社内 (72)発明者 村木 秀昭 愛知県愛知郡長久手町大字長湫字横道41番 地の１ 株式会社豊田中央研究所内 (72)発明者 新庄 博文 愛知県愛知郡長久手町大字長湫字横道41番 地の１ 株式会社豊田中央研究所内 (72)発明者 斎木 基久 愛知県愛知郡長久手町大字長湫字横道41番 地の１ 株式会社豊田中央研究所内 (72)発明者 笠原 光一 静岡県小笠郡大東町千浜7800番地 キャタ ラー工業株式会社内 (72)発明者 立石 修士 静岡県小笠郡大東町千浜7800番地 キャタ ラー工業株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takaaki Kanazawa 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Tsuneyuki Tanizawa 1 Toyota Town, Aichi Prefecture, Toyota Motor Corporation ( 72) Inventor Tatsuji Mizuno 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Corporation (72) Inventor Satoshi Iguchi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation, (72) Inventor, Kenji Kato Aichi Prefecture Toyota City, Toyota City 1 Toyota Motor Co., Ltd. (72) Inventor Toshiaki Tanaka 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd. (72) Shinichi Takeshima 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto Car Co., Ltd. (72) Inventor Tetsuro Kihara 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation Inside the company (72) Hideaki Muraki Hideaki Muraki 41, Nagachote, Nagakute-cho, Aichi-gun, Aichi Prefecture 1 of Toyota Central Research Institute Co., Ltd. 1 In the Toyota Central Research Institute Co., Ltd. (72) Inventor Motohisa Saiki, Nagachite Town, Aichi Prefecture Higashimachi Chihama 7800, Cataler Industry Co., Ltd. (72) Inventor Master Tateishi 7800 Chihama, Daitocho, Ogasa-gun, Shizuoka Prefecture Cataler Industry Co., Ltd.
Claims (1)
一酸化炭素、炭化水素および窒素酸化物を同時に浄化す
る排気ガスの浄化方法であって、酸素過剰の排気ガス
を、多孔質体からなる担体に、アルカリ土類金属酸化物
および白金を担持してなる排気ガス浄化用触媒と接触さ
せることを特徴とする排気ガスの浄化方法。1. A method for purifying exhaust gas, which comprises simultaneously purifying carbon monoxide, hydrocarbons and nitrogen oxides in the exhaust gas under an oxygen-rich atmosphere, wherein the oxygen-rich exhaust gas is a carrier made of a porous material. In addition, the method for purifying exhaust gas is characterized in that it is brought into contact with an exhaust gas purifying catalyst which carries an alkaline earth metal oxide and platinum.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13090492A JP3328318B2 (en) | 1992-05-22 | 1992-05-22 | Exhaust gas purification method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13090492A JP3328318B2 (en) | 1992-05-22 | 1992-05-22 | Exhaust gas purification method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05317652A true JPH05317652A (en) | 1993-12-03 |
| JP3328318B2 JP3328318B2 (en) | 2002-09-24 |
Family
ID=15045449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13090492A Expired - Lifetime JP3328318B2 (en) | 1992-05-22 | 1992-05-22 | Exhaust gas purification method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3328318B2 (en) |
Cited By (38)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0653238A1 (en) | 1993-11-17 | 1995-05-17 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| EP0664147A2 (en) * | 1994-01-20 | 1995-07-26 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| EP0687495A2 (en) | 1994-06-17 | 1995-12-20 | ICT Co., Ltd. | Catalyst for purifying exhaust gas from lean burn engine and method for purification |
| EP0692302A2 (en) | 1994-07-12 | 1996-01-17 | Cataler Industrial Co., Ltd. | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| EP0707882A1 (en) | 1994-10-21 | 1996-04-24 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| US5547913A (en) * | 1993-12-17 | 1996-08-20 | Toyota Jidosha Kabushiki Kaisha | Process for producing exhaust-gases-purifying catalyst |
| JPH08281116A (en) * | 1995-04-10 | 1996-10-29 | Toyota Motor Corp | Catalyst for purifying exhaust gas |
| US5575983A (en) * | 1993-09-24 | 1996-11-19 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| EP0771584A1 (en) | 1995-10-31 | 1997-05-07 | Toyota Jidosha Kabushiki Kaisha | Heat-resistant catalyst support |
| EP0786285A2 (en) | 1996-01-29 | 1997-07-30 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Exhaust gas purifying catalyst, and method for purifying exhaustgas |
| EP0787522A2 (en) | 1996-02-02 | 1997-08-06 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gas and process for producing the same |
| US5702675A (en) * | 1994-12-16 | 1997-12-30 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for producing the same |
| US5727385A (en) * | 1995-12-08 | 1998-03-17 | Ford Global Technologies, Inc. | Lean-burn nox catalyst/nox trap system |
| US5750082A (en) * | 1995-09-21 | 1998-05-12 | Ford Global Technologies, Inc. | Nox trap with improved performance |
| US5837212A (en) * | 1995-09-21 | 1998-11-17 | Ford Global Technologies, Inc. | Potassium/manganese nitrogen oxide traps for lean-burn engine operation |
| US5849661A (en) * | 1995-03-10 | 1998-12-15 | Toyota Jidosha Kabushiki Kaisha | Automotive exhaust catalyst |
| US5898015A (en) * | 1995-09-19 | 1999-04-27 | Ngk Spark Plug Co., Ltd. | Material for absorbing nitrogen oxides comprising hollandite-type complex oxide |
| US5911960A (en) * | 1993-01-11 | 1999-06-15 | Toyota Jidosha Kabushiki Kaisha | Process for purifying exhaust gases |
| JPH11156159A (en) * | 1997-09-25 | 1999-06-15 | Mazda Motor Corp | Exhaust gas cleaning device, exhaust gas cleaning material and manufacture of exhaust gas cleaning material |
| US5968462A (en) * | 1994-02-04 | 1999-10-19 | Toyota Jidosha Kabushiki Kaisha | Process for purifying exhaust gases |
| US5972830A (en) * | 1994-12-19 | 1999-10-26 | Toyota Jidosha Kabushiki Kaisha | High heat-resistant catalyst with a porous ceria support |
| US6001319A (en) * | 1995-09-19 | 1999-12-14 | Ngk Spark Plug Co., Ltd. | Method of removing nitrogen oxides using material for absorbing nitrogen oxides |
| US6004521A (en) * | 1994-02-23 | 1999-12-21 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| US6025297A (en) * | 1996-11-14 | 2000-02-15 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gas and process for producing the same |
| US6149877A (en) * | 1997-01-21 | 2000-11-21 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst |
| US6159897A (en) * | 1993-12-07 | 2000-12-12 | Toyota Jidosha Kabushiki Kaisha And Cataler Industrial Co., Ltd. | Catalyst for purifying exhaust gases |
| US6165429A (en) * | 1997-01-10 | 2000-12-26 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst and exhaust gas purifying method |
| WO2003100228A1 (en) | 2002-05-24 | 2003-12-04 | Johnson Matthey Public Limited Company | Spark ignition engine including three-way catalyst with nox storage component |
| US6806225B1 (en) | 1998-06-30 | 2004-10-19 | Toyota Jidosha Kabushiki Kaisha | Catalyst for exhaust gas purification, process for producing the same, and method of purifying exhaust gas |
| US6911184B1 (en) | 1999-10-21 | 2005-06-28 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Exhaust emission control system and method for internal combustion engines |
| DE102004012272B4 (en) * | 2003-03-13 | 2006-03-02 | Nissan Motor Co., Ltd., Yokohama | An exhaust purifying catalyst, an exhaust gas purifying catalyst manufacturing method, an exhaust gas purifying system, and an exhaust gas purifying method |
| US7056859B2 (en) | 2002-03-19 | 2006-06-06 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| JP2006297235A (en) * | 2005-04-18 | 2006-11-02 | Toyota Motor Corp | MANUFACTURING METHOD OF CATALYST HAVING NOx OCCLUDING MATERIAL |
| US7220702B2 (en) | 2001-02-19 | 2007-05-22 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification catalyst |
| WO2007111004A1 (en) | 2006-03-28 | 2007-10-04 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Catalyst for purifying exhaust gas, method of regenerating the same, exhaust gas purification apparatus using the same and method of purifying exhaust gas |
| JP2012236193A (en) * | 1993-04-28 | 2012-12-06 | Nippon Shokubai Co Ltd | Method of removing nitrogen oxides in exhaust gas |
| WO2014135937A2 (en) | 2013-03-05 | 2014-09-12 | Toyota Jidosha Kabushiki Kaisha | Diesel exhaust gas oxidation catalyst, and method for purifying diesel exhaust gas by using same |
| JP2016036783A (en) * | 2014-08-08 | 2016-03-22 | トヨタ自動車株式会社 | NOx OCCLUSION REDUCTION TYPE CATALYST AND MANUFACTURING METHOD THEREFOR |
-
1992
- 1992-05-22 JP JP13090492A patent/JP3328318B2/en not_active Expired - Lifetime
Cited By (51)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5911960A (en) * | 1993-01-11 | 1999-06-15 | Toyota Jidosha Kabushiki Kaisha | Process for purifying exhaust gases |
| JP2012236193A (en) * | 1993-04-28 | 2012-12-06 | Nippon Shokubai Co Ltd | Method of removing nitrogen oxides in exhaust gas |
| US5575983A (en) * | 1993-09-24 | 1996-11-19 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| US5922293A (en) * | 1993-11-17 | 1999-07-13 | Toyota Jidosha Kabushiki Kaisha | Process for purifying exhaust gases |
| EP0653238A1 (en) | 1993-11-17 | 1995-05-17 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| US6159897A (en) * | 1993-12-07 | 2000-12-12 | Toyota Jidosha Kabushiki Kaisha And Cataler Industrial Co., Ltd. | Catalyst for purifying exhaust gases |
| US5547913A (en) * | 1993-12-17 | 1996-08-20 | Toyota Jidosha Kabushiki Kaisha | Process for producing exhaust-gases-purifying catalyst |
| EP0658370B1 (en) * | 1993-12-17 | 2003-01-08 | Toyota Jidosha Kabushiki Kaisha | Process for producing exhaust-gases-purifying catalyst |
| US6217831B1 (en) | 1994-01-20 | 2001-04-17 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| EP0664147A3 (en) * | 1994-01-20 | 1996-10-02 | Toyota Motor Co Ltd | Catalyst for purifying exhaust gases. |
| EP0664147A2 (en) * | 1994-01-20 | 1995-07-26 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| US5849254A (en) * | 1994-01-20 | 1998-12-15 | Toyota Jidosha Kabushiki Kaisha | Method for purifying exhaust gases with two layer catalyst in oxygen-rich atmosphere |
| US5968462A (en) * | 1994-02-04 | 1999-10-19 | Toyota Jidosha Kabushiki Kaisha | Process for purifying exhaust gases |
| US6004521A (en) * | 1994-02-23 | 1999-12-21 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| EP0687495A2 (en) | 1994-06-17 | 1995-12-20 | ICT Co., Ltd. | Catalyst for purifying exhaust gas from lean burn engine and method for purification |
| EP0692302A2 (en) | 1994-07-12 | 1996-01-17 | Cataler Industrial Co., Ltd. | Catalyst for purifying exhaust gases and process for purifying exhaust gases |
| US5762892A (en) * | 1994-07-12 | 1998-06-09 | Cataler Industrial Co., Ltd. | Process for purifying exhaust gases |
| EP0707882A1 (en) | 1994-10-21 | 1996-04-24 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| US5804152A (en) * | 1994-10-21 | 1998-09-08 | Toyota Jidosha Kabushiki Kaisha | Method for purifying exhaust gases |
| US5702675A (en) * | 1994-12-16 | 1997-12-30 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases and process for producing the same |
| US5972830A (en) * | 1994-12-19 | 1999-10-26 | Toyota Jidosha Kabushiki Kaisha | High heat-resistant catalyst with a porous ceria support |
| US5849661A (en) * | 1995-03-10 | 1998-12-15 | Toyota Jidosha Kabushiki Kaisha | Automotive exhaust catalyst |
| JPH08281116A (en) * | 1995-04-10 | 1996-10-29 | Toyota Motor Corp | Catalyst for purifying exhaust gas |
| US5898015A (en) * | 1995-09-19 | 1999-04-27 | Ngk Spark Plug Co., Ltd. | Material for absorbing nitrogen oxides comprising hollandite-type complex oxide |
| US6001319A (en) * | 1995-09-19 | 1999-12-14 | Ngk Spark Plug Co., Ltd. | Method of removing nitrogen oxides using material for absorbing nitrogen oxides |
| US5837212A (en) * | 1995-09-21 | 1998-11-17 | Ford Global Technologies, Inc. | Potassium/manganese nitrogen oxide traps for lean-burn engine operation |
| US5750082A (en) * | 1995-09-21 | 1998-05-12 | Ford Global Technologies, Inc. | Nox trap with improved performance |
| EP0771584A1 (en) | 1995-10-31 | 1997-05-07 | Toyota Jidosha Kabushiki Kaisha | Heat-resistant catalyst support |
| US6083868A (en) * | 1995-10-31 | 2000-07-04 | Toyota Jidosha Kabushiki Kaisha | Method of producing heat-resistant catalyst support |
| US5727385A (en) * | 1995-12-08 | 1998-03-17 | Ford Global Technologies, Inc. | Lean-burn nox catalyst/nox trap system |
| EP0786285A2 (en) | 1996-01-29 | 1997-07-30 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Exhaust gas purifying catalyst, and method for purifying exhaustgas |
| US6251820B1 (en) | 1996-02-02 | 2001-06-26 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gas and process for producing the same |
| EP0787522A2 (en) | 1996-02-02 | 1997-08-06 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gas and process for producing the same |
| US6025297A (en) * | 1996-11-14 | 2000-02-15 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gas and process for producing the same |
| US6165429A (en) * | 1997-01-10 | 2000-12-26 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst and exhaust gas purifying method |
| US6149877A (en) * | 1997-01-21 | 2000-11-21 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purifying catalyst |
| JPH11156159A (en) * | 1997-09-25 | 1999-06-15 | Mazda Motor Corp | Exhaust gas cleaning device, exhaust gas cleaning material and manufacture of exhaust gas cleaning material |
| US6806225B1 (en) | 1998-06-30 | 2004-10-19 | Toyota Jidosha Kabushiki Kaisha | Catalyst for exhaust gas purification, process for producing the same, and method of purifying exhaust gas |
| US6911184B1 (en) | 1999-10-21 | 2005-06-28 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Exhaust emission control system and method for internal combustion engines |
| US7220702B2 (en) | 2001-02-19 | 2007-05-22 | Toyota Jidosha Kabushiki Kaisha | Exhaust gas purification catalyst |
| US7229947B2 (en) | 2001-02-19 | 2007-06-12 | Toyota Jidosha Kabushiki Kaisha | Catalyst for hydrogen generation and catalyst for purifying of exhaust gas |
| US7056859B2 (en) | 2002-03-19 | 2006-06-06 | Toyota Jidosha Kabushiki Kaisha | Catalyst for purifying exhaust gases |
| WO2003100228A1 (en) | 2002-05-24 | 2003-12-04 | Johnson Matthey Public Limited Company | Spark ignition engine including three-way catalyst with nox storage component |
| DE102004012272B4 (en) * | 2003-03-13 | 2006-03-02 | Nissan Motor Co., Ltd., Yokohama | An exhaust purifying catalyst, an exhaust gas purifying catalyst manufacturing method, an exhaust gas purifying system, and an exhaust gas purifying method |
| JP2006297235A (en) * | 2005-04-18 | 2006-11-02 | Toyota Motor Corp | MANUFACTURING METHOD OF CATALYST HAVING NOx OCCLUDING MATERIAL |
| JP4595644B2 (en) * | 2005-04-18 | 2010-12-08 | トヨタ自動車株式会社 | Method for producing catalyst having NOx storage material |
| WO2007111004A1 (en) | 2006-03-28 | 2007-10-04 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Catalyst for purifying exhaust gas, method of regenerating the same, exhaust gas purification apparatus using the same and method of purifying exhaust gas |
| US8105561B2 (en) | 2006-03-28 | 2012-01-31 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Catalyst for purification of exhaust gas, regeneration method for the catalyst, and apparatus and method for purification of exhaust gas using the catalyst |
| EP2527033A1 (en) | 2006-03-28 | 2012-11-28 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Catalyst for purification of exhaust gas, regeneration method for the catalyst, and apparatus and method for purification of exhaust gas using the catalyst |
| WO2014135937A2 (en) | 2013-03-05 | 2014-09-12 | Toyota Jidosha Kabushiki Kaisha | Diesel exhaust gas oxidation catalyst, and method for purifying diesel exhaust gas by using same |
| JP2016036783A (en) * | 2014-08-08 | 2016-03-22 | トヨタ自動車株式会社 | NOx OCCLUSION REDUCTION TYPE CATALYST AND MANUFACTURING METHOD THEREFOR |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3328318B2 (en) | 2002-09-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3328318B2 (en) | Exhaust gas purification method | |
| JP3291086B2 (en) | Exhaust gas purification catalyst and exhaust gas purification method | |
| EP1007190B1 (en) | Catalytic converter for a lean burn internal combustion engine | |
| US4957896A (en) | Catalyst for purification of exhaust gases | |
| JP3328322B2 (en) | Exhaust gas purification method | |
| JP3391878B2 (en) | Exhaust gas purification catalyst | |
| JPH05168860A (en) | Purifying method of exhaust gas | |
| JP3311012B2 (en) | Exhaust gas purification catalyst and exhaust gas purification method | |
| JPH0899034A (en) | Catalyst for purifying exhaust gas | |
| JPH07213902A (en) | Exhaust gas purifying catalyst | |
| JPH09500570A (en) | Layered catalyst composite | |
| US6010673A (en) | Method for purifying exhaust gas | |
| JP3433956B2 (en) | Exhaust gas purification method | |
| JP3409894B2 (en) | Exhaust gas purification catalyst and exhaust gas purification method | |
| JPH09215922A (en) | Catalyst for purifying exhaust gas | |
| JP3303486B2 (en) | Method for producing exhaust gas purifying catalyst | |
| JP3488487B2 (en) | Exhaust gas purification method | |
| JP3224054B2 (en) | Exhaust gas purification method | |
| JPS6117544B2 (en) | ||
| JPH0985093A (en) | Catalyst for cleaning exhaust gas | |
| JP2003326137A (en) | Exhaust gas purification method and catalyst for exhaust gas purification | |
| JPH06165920A (en) | Exhaust gas purifying method | |
| JPH10216514A (en) | Catalyst for exhaust gas purification | |
| JP3154620B2 (en) | Exhaust gas purification catalyst and exhaust gas purification method | |
| JPH0857314A (en) | Catalyst for purification of exhaust gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080712 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080712 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090712 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090712 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100712 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110712 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110712 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120712 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120712 Year of fee payment: 10 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313532 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120712 Year of fee payment: 10 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| EXPY | Cancellation because of completion of term |