JPH0549929A - Catalyst for purifying exhaust gas - Google Patents
Catalyst for purifying exhaust gasInfo
- Publication number
- JPH0549929A JPH0549929A JP3213841A JP21384191A JPH0549929A JP H0549929 A JPH0549929 A JP H0549929A JP 3213841 A JP3213841 A JP 3213841A JP 21384191 A JP21384191 A JP 21384191A JP H0549929 A JPH0549929 A JP H0549929A
- Authority
- JP
- Japan
- Prior art keywords
- catalyst
- rhodium
- exhaust gas
- inlet side
- outlet side
- 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.)
- Pending
Links
- 239000003054 catalyst Substances 0.000 title claims abstract description 48
- 239000010948 rhodium Substances 0.000 claims abstract description 44
- 229910052703 rhodium Inorganic materials 0.000 claims abstract description 43
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims abstract description 41
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 37
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 36
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 18
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 18
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 7
- 230000006866 deterioration Effects 0.000 abstract description 5
- 239000007789 gas Substances 0.000 description 41
- 239000010410 layer Substances 0.000 description 17
- 230000000052 comparative effect Effects 0.000 description 12
- 230000000694 effects Effects 0.000 description 10
- 238000000746 purification Methods 0.000 description 9
- 239000007864 aqueous solution Substances 0.000 description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000006555 catalytic reaction Methods 0.000 description 2
- 229910052878 cordierite Inorganic materials 0.000 description 2
- 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 2
- 238000006073 displacement reaction Methods 0.000 description 2
- SONJTKJMTWTJCT-UHFFFAOYSA-K rhodium(iii) chloride Chemical compound [Cl-].[Cl-].[Cl-].[Rh+3] SONJTKJMTWTJCT-UHFFFAOYSA-K 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000003283 rhodium Chemical class 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
- Catalysts (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、車両の排ガス系統に配
置、使用される排ガス浄化用触媒に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas purifying catalyst arranged and used in an exhaust gas system of a vehicle.
【０００２】[0002]
【従来の技術】エンジンより排出された排ガス中の有害
物質であるＨＣ、ＣＯ、ＮＯｘを同時に効率よく無害化
するのに有効な三元触媒が用いられている。また、三元
触媒として特開昭６２ー６８５４２号公報にみられるよ
うに、白金（Ｐｔ）ーパラジウム（Ｐｄ）ーロジウム
（Ｒｈ）の触媒活性性能が、リンや鉛などの被毒により
劣化することを制御するために、一体型構造体の担体の
排ガス入口側にパラジウム及びロジウムを、その後ろ
（排ガス出口側）に白金及びロジウムを担持した触媒が
知られている。2. Description of the Related Art A three-way catalyst which is effective in detoxifying harmful substances such as HC, CO and NOx in exhaust gas discharged from an engine at the same time is used. Further, as disclosed in JP-A-62-68542 as a three-way catalyst, the catalytic activity performance of platinum (Pt) -palladium (Pd) -rhodium (Rh) is deteriorated due to poisoning of phosphorus, lead and the like. For the purpose of control, a catalyst is known in which palladium and rhodium are supported on the exhaust gas inlet side of a carrier of an integral structure, and platinum and rhodium are supported behind it (exhaust gas outlet side).
【０００３】[0003]
【発明が解決しようとする課題】前記特開昭６２ー６８
５４２号公報に開示された排ガス浄化用触媒は、窒素酸
化物を浄化する白金や、パラジウムの活性性能を保持す
るために必要なロジウムの担持量が前記入口側と前記出
口側とでは、触媒温度が異なるのにかかわらず、前記入
口側から前記出口側に均一となっているため、触媒担持
層に担持された触媒活性成分である白金、パラジウム、
ロジウムが熱劣化により粒成長したり、ロジウムがパラ
ジウムに覆われることにより、ロジウムが白金や、パラ
ジウムの活性性能を向上させる影響力が小さくなって、
触媒全体の活性性能が充分に発揮されず、耐久後の浄化
率が低下する。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention JP-A-62-68
In the exhaust gas purifying catalyst disclosed in Japanese Patent No. 542, platinum is used to purify nitrogen oxides, and the amount of rhodium required to retain the activity performance of palladium is different between the inlet side and the outlet side. Despite being different, since it is uniform from the inlet side to the outlet side, platinum is a catalytically active component supported on the catalyst-supporting layer, palladium,
Grain growth of rhodium due to heat deterioration or covering of rhodium with palladium reduces the influence of rhodium on platinum and the activity performance of palladium,
The activity performance of the entire catalyst is not sufficiently exhibited, and the purification rate after endurance is reduced.
【０００４】本発明は、耐熱性に優れ、触媒活性成分の
熱劣化を低減し、耐久後の浄化率を向上することを目的
とする。It is an object of the present invention to have excellent heat resistance, reduce thermal deterioration of catalytically active components, and improve purification rate after endurance.
【０００５】[0005]
【課題を解決するための手段】本発明の排ガス浄化用触
媒は、主として活性アルミナからなる触媒担持層をもつ
一体型構造体の排ガスが流入する入口側にパラジウム及
びロジウムが担持され排ガスが流出する出口側に白金及
びロジウムが担持された触媒であって、前記触媒担持層
の前記ロジウムの担持量は、前記入口側より前記出口側
が多いことを特徴とする。In the exhaust gas purifying catalyst of the present invention, palladium and rhodium are carried on the inlet side of the integrated structure having a catalyst supporting layer mainly made of activated alumina and the exhaust gas flows out. The catalyst has platinum and rhodium supported on the outlet side, and the amount of rhodium supported on the catalyst supporting layer is larger on the outlet side than on the inlet side.
【０００６】一体型構造体としては、主として活性アル
ミナからなる触媒担持層をもつものであればよく、例え
ば、市販のコージェライト製モノリス担体や、メタル担
体等を用いることができる。触媒担持層に担持されるロ
ジウムの担持量を、前記入口側より前記出口側が多いと
は、例えば、ロジウムの担持量が入口側領域より出口側
領域に向けて漸増する分布勾配としたり、ロジウムの担
持量が入口側領域より出口側領域に向けて段階的に増加
させたり、ロジウムの担持量が入口側領域より出口側領
域に多くさせ、更に入口側領域と出口側領域とを両者の
中間で部分的にだぶらせたりすることができる。The monolithic structure may be one having a catalyst supporting layer mainly composed of activated alumina, and for example, a commercially available cordierite monolith carrier, a metal carrier or the like can be used. The amount of rhodium supported on the catalyst-supporting layer is greater on the outlet side than on the inlet side, for example, a distribution gradient in which the amount of rhodium supported gradually increases from the inlet side region toward the outlet side region, or rhodium The carrying amount is increased stepwise from the inlet side region to the outlet side region, or the carrying amount of rhodium is increased from the inlet side region to the outlet side region, and the inlet side region and the outlet side region are located in the middle of both. It can be partially blunted.
【０００７】前記一体型構造体のガス入口側の触媒担持
層に担持されるパラジウムの担持領域は、ガス流れ方向
の長さが、ガス出口側に担持される白金の担持領域の長
さの０．５〜２倍とすることが好ましい。ロジウムの担
持量をガス入口側よりガス出口側に向けて漸増する分布
勾配とするには、例えば、ガス入口側の担持密度を
Ｄ1 、ガス出口側の担持密度をＤ2 とすると、 Ｄ1 ／
Ｄ2 ＝０．９５〜０．０１５の範囲で漸増する分布勾配
とすることが好ましい。The palladium carrying region carried on the catalyst carrying layer on the gas inlet side of the integrated structure has a length in the gas flow direction which is 0 times the length of the platinum carrying region carried on the gas outlet side. It is preferably 0.5 to 2 times. To make the distribution gradient in which the amount of rhodium carried gradually increases from the gas inlet side toward the gas outlet side, for example, let D 1 be the carrying density on the gas inlet side, and D 2 be the carrying density on the gas outlet side, then D 1 /
It is preferable that the distribution gradient is gradually increased in the range of D 2 = 0.95 to 0.015.
【０００８】[0008]
【作用および効果】本発明の排ガス浄化用触媒は、主と
して活性アルミナからなる触媒担持層をもつ一体型構造
体の排ガスが流入する入口側にパラジウム及びロジウム
が担持され排ガスが流出する出口側に白金及びロジウム
が担持された触媒であって、前記触媒担持層の前記ロジ
ウムの担持量は、前記入口側より前記出口側が多いこと
を特徴とする。The function and effect of the exhaust gas purifying catalyst of the present invention are as follows: Palladium and rhodium are supported on the inlet side of exhaust gas and platinum on the outlet side of exhaust gas of an integrated structure having a catalyst supporting layer mainly composed of activated alumina. And a catalyst supporting rhodium, wherein the amount of rhodium carried in the catalyst carrying layer is larger on the outlet side than on the inlet side.
【０００９】このため、一体型構造体の触媒担持層に
は、排ガスが流入する入口側領域よりも、触媒反応熱が
高温となる出口側領域にロジウムが多く存在する。そし
てこのロジウムにより耐熱性を保持することができる。
またロジウムが増加した分、白金の活性が熱劣化するこ
とや、凝集劣化することを低減でき、白金の熱的安定性
が増加すると考えられる。このため、白金の優れた高温
活性を充分に発揮し得る。Therefore, in the catalyst-supporting layer of the integral structure, a large amount of rhodium is present in the outlet side area where the heat of the catalytic reaction becomes higher than in the inlet side area where the exhaust gas flows. This rhodium can maintain heat resistance.
Further, it is considered that the increase of rhodium can reduce the thermal deterioration of the activity of platinum and the deterioration of aggregation, and the thermal stability of platinum is increased. Therefore, the excellent high temperature activity of platinum can be sufficiently exhibited.
【００１０】また、前記入口側領域では、前記出口側領
域よりも触媒反応熱が低く、分布するロジウム量が少な
いため、ロジウムがパラジウムに覆われて活性を失なう
ことを低減することができる。そして、ロジウムの活性
が保持されることでパラジウムの優れた低温活性を充分
に発揮し得る。従って本発明の排ガス浄化用触媒は、従
来触媒に対し、耐熱性が向上し、三元触媒としてＨＣ、
ＣＯ、ＮＯｘの浄化性能を向上することができる。Further, in the inlet side region, the catalytic reaction heat is lower than in the outlet side region and the amount of rhodium distributed is small, so that it is possible to reduce loss of activity due to the rhodium being covered with palladium. .. Then, by retaining the activity of rhodium, the excellent low-temperature activity of palladium can be sufficiently exerted. Therefore, the exhaust gas-purifying catalyst of the present invention has improved heat resistance as compared with the conventional catalyst, and HC as a three-way catalyst,
CO and NOx purification performance can be improved.
【００１１】[0011]
【実施例】本発明の排ガス浄化用触媒の実施例を以下に
説明する。本実施例では、予め、一体型構造体として、
市販の短径９５ｍｍ、長径１４７、長さ１５０ｍｍのコ
ージェライト製モノリス担体が準備された。このモノリ
ス担体は、活性アルミナ粉末、水、バインダ−を混合攪
拌して調整されたスラリ−中に約６０秒間浸漬させる。
そしてスラリ−中より取り出され、余分なスラリ−を吹
き払い。３００度で１時間乾燥した後、７００度で１時
間焼成し、モノリス担体の多数の細い貫通孔内周面に主
として活性アルミナからなる触媒担持層形成される。こ
の触媒担持層中には、希土類元素が含まれていてもよ
い。EXAMPLES Examples of the exhaust gas purifying catalyst of the present invention will be described below. In this embodiment, as an integrated structure,
A commercially available cordierite monolithic carrier having a short diameter of 95 mm, a long diameter of 147 and a length of 150 mm was prepared. The monolith carrier is immersed in a slurry prepared by mixing and stirring activated alumina powder, water and a binder for about 60 seconds.
Then it is taken out of the slurry and the excess slurry is blown off. After drying at 300 ° C. for 1 hour, it is baked at 700 ° C. for 1 hour to form a catalyst supporting layer mainly made of activated alumina on the inner peripheral surface of a large number of thin through holes of the monolith carrier. A rare earth element may be contained in the catalyst supporting layer.
【００１２】次いで、触媒担持層を形成したモノリス担
体は、排ガスが流入する入口側領域と、排ガスが流出す
る出口側領域が別々に、以下に示す溶液に順次浸漬され
る。すなわち、モノリス担体は、まず、前記入口側領域
が別途用意された硝酸パラジウム水溶液および塩化ロジ
ウム水溶液に浸漬され、前記出口側領域がジニトロジア
ンミン白金酸水溶液および塩化ロジウム水溶液に浸漬さ
れる。Next, the monolith carrier having the catalyst supporting layer formed thereon is successively immersed in the solution shown below, separately from the inlet side region into which the exhaust gas flows and the outlet side region from which the exhaust gas flows out. That is, in the monolithic carrier, first, the inlet side region is immersed in a separately prepared aqueous solution of palladium nitrate and rhodium chloride, and the outlet side region is immersed in the dinitrodiammineplatinic acid aqueous solution and the rhodium chloride aqueous solution.
【００１３】これによって、モノリス担体の触媒担持層
には、排気ガス入り口側端面から排ガス出口側に向う長
さＬ７５までの入口側領域にパラジウムが２ｇ，ロジウ
ムが０．１５ｇ担持される。また、排ガス出口側から排
ガス入口側に向う長さＬ７５の出口側領域に白金が１．
５ｇ，ロジウムが０．３５ｇ担持される。そして、触媒
担持層の入口側領域にパラジウムおよびロジウムが担持
され、前記出口側領域に白金およびロジウムが担持さ
れ、かつロジウムの担持量が入口側領域より出口側領域
に向けて多くした排ガス浄化用触媒が得られた。As a result, 2 g of palladium and 0.15 g of rhodium are loaded on the catalyst-supporting layer of the monolith carrier in the inlet side region from the end face on the exhaust gas inlet side to the length L75 facing the exhaust gas outlet side. In addition, platinum is formed on the outlet side region of the length L75 extending from the exhaust gas outlet side toward the exhaust gas inlet side with 1.
5 g and 0.35 g of rhodium are carried. Then, palladium and rhodium are carried in the inlet side area of the catalyst carrying layer, platinum and rhodium are carried in the outlet side area, and the amount of rhodium carried is increased from the inlet side area toward the outlet side area for exhaust gas purification. A catalyst was obtained.
【００１４】（比較例）前記実施例の排ガス浄化用触媒
の効果を確認するため比較例１、２、３の排ガス浄化用
触媒が形成された。 （比較例１）比較例１の排ガス浄化用触媒は、実施例と
同じ触媒担持層を形成したモノリス担体に、その入口側
領域にパラジウムが２ｇ，ロジウムが０．２５ｇ担持さ
れ、出口側領域に白金が１．５ｇ，ロジウムが０．２５
ｇ担持され、かつ入口側領域と出口側領域とのロジウム
の担持量が同じ分布であること以外は、前記実施例と同
じである。(Comparative Example) In order to confirm the effect of the exhaust gas purifying catalyst of the above example, the exhaust gas purifying catalysts of Comparative Examples 1, 2 and 3 were formed. (Comparative Example 1) In the exhaust gas purifying catalyst of Comparative Example 1, 2 g of palladium and 0.25 g of rhodium were supported in the inlet side region and the outlet side region of the monolith carrier having the same catalyst supporting layer as in the example. 1.5g platinum, 0.25 rhodium
This is the same as the above-described example except that g is supported and the amounts of rhodium carried in the inlet region and the outlet region are the same.
【００１５】（比較例２）比較例２の排ガス浄化用触媒
は、実施例と同じ触媒担持層を形成したモノリス担体
に、その入口側領域にパラジウムが２ｇ，ロジウムが
０．３５ｇ担持され、出口側領域に白金が１．５ｇ，ロ
ジウムが０．１５ｇ担持され、かつ入口側領域より出口
側領域に向かってロジウムの担持量が少なくなった分布
勾配となっていること以外は、前記実施例と同じであ
る。(Comparative Example 2) The exhaust gas purifying catalyst of Comparative Example 2 has a monolith carrier having the same catalyst carrying layer as that of the embodiment, in which 2 g of palladium and 0.35 g of rhodium are carried in the inlet side region, and the outlet is Platinum of 1.5 g and rhodium of 0.15 g were carried in the side region, and the distribution gradient was such that the amount of rhodium carried decreased from the inlet side region toward the outlet side region. Is the same.
【００１６】（比較例３）比較例３の排ガス浄化用触媒
は、実施例と同じ触媒担持層を形成したモノリス担体
に、その入口側領域にパラジウムが２ｇ担持され、出口
側領域に白金が１．５ｇ，ロジウムが０．５ｇ担持さ
れ、かつ入口側領域にロジウムが担持されていないこと
以外は、前記実施例と同じである。 （耐久試験）市販のＶ型排気量３０００ｃｃのエンジン
の左右バンクに、前記実施例および比較例１、２、３の
排ガス浄化用触媒がそれぞれ別途に装着され耐久試験が
実施された。(Comparative Example 3) In the exhaust gas purifying catalyst of Comparative Example 3, 2 g of palladium was loaded in the inlet side region and 1% of platinum was loaded in the outlet side region of the monolith carrier having the same catalyst supporting layer as in the example. 0.5 g, rhodium 0.5 g are supported, and rhodium is not supported in the inlet side region, which is the same as the above embodiment. (Durability Test) The exhaust gas purifying catalysts of Examples and Comparative Examples 1, 2, and 3 were separately attached to the left and right banks of a commercially available V-type engine having a displacement of 3000 cc, and a durability test was performed.
【００１７】耐久試験条件は、触媒入りガス温度８５０
℃，排気ガス雰囲気ストイキ、耐久時間１００ｈであっ
た。 （触媒活性性能比較評価）また、市販の排気量２０００
ｃｃのエンジンを用いて、前記実施例および比較例１、
２、３の排ガス浄化用触媒の触媒入りガス温度と排ガス
の浄化率との関係を評価した。The endurance test condition is that the temperature of the gas containing the catalyst is 850.
C., exhaust gas atmosphere stoichiometry, durability time 100 h. (Comparison evaluation of catalytic activity performance) Also, a commercial displacement 2000
Using the engine of cc, the above-mentioned Example and Comparative Example 1,
The relationship between the temperature of gas entering the catalyst and the purification rate of the exhaust gas of a few exhaust gas purification catalysts was evaluated.
【００１８】この結果を表１に温度数値として示す。な
お、温度数値は、排ガス浄化率が５０％に達する触媒入
りガス温度である。（前記温度数値が低いほど触媒性能
は良好である。）上記実施例、比較例１、２、３につい
て耐久後の性能を表１に示す。The results are shown in Table 1 as temperature numerical values. The temperature value is the temperature of the gas containing the catalyst at which the exhaust gas purification rate reaches 50%. (The lower the temperature value is, the better the catalyst performance is.) Table 1 shows the performance after endurance of the above Examples and Comparative Examples 1, 2, and 3.
【００１９】[0019]
【表１】 この結果、本実施例の場合、ＨＣ、ＣＯ、ＮＯｘいずれ
かの排ガスの浄化率が５０％に達する温度数値は、比較
例１、２、３の温度数値よりも低く耐久性に優れている
ことが判明した。また、これにより、三元触媒としてＨ
Ｃ、ＣＯ、ＮＯｘの浄化性能を向上することができる。[Table 1] As a result, in the case of this example, the temperature value at which the purification rate of exhaust gas of HC, CO, or NOx reaches 50% is lower than the temperature values of Comparative Examples 1, 2, and 3 and has excellent durability. There was found. In addition, as a three-way catalyst, H
The purification performance of C, CO, and NOx can be improved.
Claims (1)
をもつ一体型構造体の排ガスが流入する入口側にパラジ
ウム及びロジウムが担持され排ガスが流出する出口側に
白金及びロジウムが担持された触媒であって、 前記触媒担持層の前記ロジウムの担持量は、前記入口側
より前記出口側が多いことを特徴とする排ガス浄化用触
媒。1. A catalyst in which palladium and rhodium are supported on the inlet side where exhaust gas flows in, and platinum and rhodium are supported on the outlet side where exhaust gas flows out of an integrated structure having a catalyst supporting layer mainly composed of activated alumina. The amount of rhodium carried in the catalyst carrying layer is larger on the outlet side than on the inlet side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3213841A JPH0549929A (en) | 1991-08-26 | 1991-08-26 | Catalyst for purifying exhaust gas |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3213841A JPH0549929A (en) | 1991-08-26 | 1991-08-26 | Catalyst for purifying exhaust gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0549929A true JPH0549929A (en) | 1993-03-02 |
Family
ID=16645913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3213841A Pending JPH0549929A (en) | 1991-08-26 | 1991-08-26 | Catalyst for purifying exhaust gas |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0549929A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6634168B1 (en) | 1998-10-19 | 2003-10-21 | Nissan Motor Co., Ltd. | Exhaust gas purification system |
| JP2009101252A (en) * | 2007-10-19 | 2009-05-14 | Toyota Motor Corp | Catalyst for removing exhaust gas |
| JP2012096201A (en) * | 2010-11-05 | 2012-05-24 | Toyota Motor Corp | Catalyst for cleaning automobile exhaust gas |
-
1991
- 1991-08-26 JP JP3213841A patent/JPH0549929A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6634168B1 (en) | 1998-10-19 | 2003-10-21 | Nissan Motor Co., Ltd. | Exhaust gas purification system |
| JP2009101252A (en) * | 2007-10-19 | 2009-05-14 | Toyota Motor Corp | Catalyst for removing exhaust gas |
| JP2012096201A (en) * | 2010-11-05 | 2012-05-24 | Toyota Motor Corp | Catalyst for cleaning automobile exhaust gas |
| US8603940B2 (en) | 2010-11-05 | 2013-12-10 | Toyota Jidosha Kabushiki Kaisha | Automobile exhaust gas catalytic converter |
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