JPH04334548A - Exhaust gas purifying catalyst - Google Patents
Exhaust gas purifying catalystInfo
- Publication number
- JPH04334548A JPH04334548A JP3133277A JP13327791A JPH04334548A JP H04334548 A JPH04334548 A JP H04334548A JP 3133277 A JP3133277 A JP 3133277A JP 13327791 A JP13327791 A JP 13327791A JP H04334548 A JPH04334548 A JP H04334548A
- Authority
- JP
- Japan
- Prior art keywords
- cerium
- zirconium
- catalyst
- exhaust gas
- oxide powder
- 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 62
- 239000000843 powder Substances 0.000 claims abstract description 69
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims abstract description 60
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 56
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 55
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims abstract description 50
- 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 37
- 239000010948 rhodium Substances 0.000 claims abstract description 20
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000007864 aqueous solution Substances 0.000 claims abstract description 16
- 229910052703 rhodium Inorganic materials 0.000 claims abstract description 16
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000011247 coating layer Substances 0.000 claims abstract description 12
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 6
- -1 zirconium ions Chemical class 0.000 claims abstract description 5
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 4
- 239000010410 layer Substances 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 238000001556 precipitation Methods 0.000 claims description 3
- 239000007787 solid Substances 0.000 claims description 2
- 239000002244 precipitate Substances 0.000 abstract description 5
- 238000002485 combustion reaction Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 26
- 229910000420 cerium oxide Inorganic materials 0.000 description 14
- 238000000746 purification Methods 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 13
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 13
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 9
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical class [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 9
- 229910001928 zirconium oxide Inorganic materials 0.000 description 9
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 8
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 8
- 239000002002 slurry Substances 0.000 description 8
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 7
- 229910002091 carbon monoxide Inorganic materials 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- HSJPMRKMPBAUAU-UHFFFAOYSA-N cerium(3+);trinitrate Chemical compound [Ce+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O HSJPMRKMPBAUAU-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 238000011156 evaluation Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 229910000510 noble metal Inorganic materials 0.000 description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 4
- 230000003197 catalytic effect Effects 0.000 description 4
- 239000000446 fuel Substances 0.000 description 4
- 229910017604 nitric acid Inorganic materials 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 150000000703 Cerium Chemical class 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- OERNJTNJEZOPIA-UHFFFAOYSA-N zirconium nitrate Chemical compound [Zr+4].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O OERNJTNJEZOPIA-UHFFFAOYSA-N 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- IXSUHTFXKKBBJP-UHFFFAOYSA-L azanide;platinum(2+);dinitrite Chemical compound [NH2-].[NH2-].[Pt+2].[O-]N=O.[O-]N=O IXSUHTFXKKBBJP-UHFFFAOYSA-L 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- CETPSERCERDGAM-UHFFFAOYSA-N ceric oxide Chemical compound O=[Ce]=O CETPSERCERDGAM-UHFFFAOYSA-N 0.000 description 1
- RCFVMJKOEJFGTM-UHFFFAOYSA-N cerium zirconium Chemical compound [Zr].[Ce] RCFVMJKOEJFGTM-UHFFFAOYSA-N 0.000 description 1
- WPQBNJRIWONKBL-UHFFFAOYSA-N cerium(3+);oxygen(2-);zirconium(4+) Chemical compound [O-2].[Zr+4].[Ce+3] WPQBNJRIWONKBL-UHFFFAOYSA-N 0.000 description 1
- 229910000422 cerium(IV) oxide Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000006255 coating slurry Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- UJVRJBAUJYZFIX-UHFFFAOYSA-N nitric acid;oxozirconium Chemical compound [Zr]=O.O[N+]([O-])=O.O[N+]([O-])=O UJVRJBAUJYZFIX-UHFFFAOYSA-N 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- VXNYVYJABGOSBX-UHFFFAOYSA-N rhodium(3+);trinitrate Chemical compound [Rh+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VXNYVYJABGOSBX-UHFFFAOYSA-N 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 150000003754 zirconium Chemical class 0.000 description 1
Abstract
Description
【０００１】0001
【産業上の利用分野】この発明は、自動車等の内燃機関
から排出される排ガス中の有害成分である炭化水素（Ｈ
Ｃ） 、一酸化炭素（ＣＯ） 、窒素酸化物（ＮＯｘ）
を効率よく浄化する排ガス浄化用触媒に関する。[Industrial Application Field] This invention focuses on hydrocarbons (H
C), carbon monoxide (CO), nitrogen oxides (NOx)
This invention relates to an exhaust gas purification catalyst that efficiently purifies the exhaust gas.
【０００２】0002
【従来の技術】従来、内燃機関から排出される排ガス中
のＨＣ、ＣＯ、ＮＯｘ を浄化する排ガス浄化用触媒は
種々提案されている。なかでも貴金属を活性成分とする
排ガス浄化用触媒にセリウム、ジルコニウムを適当量添
加すると触媒性能が向上することから、例えば、特開昭
６１−１５７３４７ 号公報、特開平１−１２３６３６
号公報に開示されているように、モノリス担体にセリウ
ム、ジルコニウムそれぞれの酸化物あるいは炭酸塩粉末
を活性アルミナ等と混合塗布して熱処理した触媒や、特
開昭６３−１１６７４１ 号公報、特開平１−２８１１
４４号公報に開示されているように、酸化セリウムの持
つＯ２ストレージ能向上を目的とし、セリウムを主成分
とするセリウム、ジルコニウム酸化物を添加した触媒が
提案されている。2. Description of the Related Art Conventionally, various exhaust gas purifying catalysts have been proposed for purifying HC, CO, and NOx in exhaust gas discharged from internal combustion engines. In particular, adding appropriate amounts of cerium and zirconium to exhaust gas purification catalysts containing noble metals as active ingredients improves the catalyst performance.
As disclosed in Japanese Patent Laid-Open No. 116741/1983, catalysts prepared by applying oxide or carbonate powders of cerium and zirconium mixed with activated alumina etc. on a monolithic carrier and heat-treated the same, and -2811
As disclosed in Japanese Patent No. 44, a catalyst containing cerium and zirconium oxides containing cerium as a main component has been proposed for the purpose of improving the O2 storage capacity of cerium oxide.
【０００３】0003
【発明が解決しようとする課題】しかしながら、このよ
うな従来の排ガス浄化用触媒においては、その製造工程
でセリウムおよびジルコニウムを排ガス浄化用触媒へ添
加するにあっては、
１） セリウム、ジルコニウムのそれぞれの酸化物あ
るいは炭酸塩粉末を活性アルミナ等と混合添加して熱処
理する方法ではセリウム、ジルコニウムは複合化されに
くく、複合化等の相互作用による助触媒作用は充分に得
られない。
２） また、従来報告されているセリウム、ジルコニ
ウム酸化物は、酸化セリウムを主成分としこれにジルコ
ニウム等を添加したものであるが、貴金属によってはセ
リウムを主成分とする酸化物が必ずしも触媒作用向上に
有効とはならない。等の問題点があった。[Problems to be Solved by the Invention] However, in such conventional exhaust gas purification catalysts, when adding cerium and zirconium to the exhaust gas purification catalysts in the manufacturing process, 1) cerium and zirconium are added to each of the catalysts. In the method in which oxide or carbonate powder is mixed and added with activated alumina and the like and then heat treated, cerium and zirconium are difficult to be composited, and a sufficient cocatalytic effect due to interaction such as compositeization cannot be obtained. 2) In addition, the cerium and zirconium oxides that have been reported so far are mainly composed of cerium oxide and to which zirconium etc. are added, but depending on the noble metal, cerium-based oxides do not necessarily improve the catalytic activity. It will not be valid. There were problems such as.
【０００４】0004
【課題を解決するための手段】発明者は上記問題点に鑑
み、以下に述べる新規の触媒により、従来の問題点が解
決されることを見出し、本発明を達成するに至った。即
ち、本発明の排ガス浄化用触媒は、触媒コート層がロジ
ウム或いはロジウムと白金またはパラジウムと、少くと
も、セリウム、ジルコニウムのイオンを含む水溶液から
沈澱生成反応を用いて製造された酸化物粉末と、活性ア
ルミナとを含んでなるモノリス型排ガス浄化用触媒にお
いて、該少くともセリウムとジルコニウムを含む酸化物
粉末が金属換算で１０〜３０モル％のセリウムと、７０
〜９０モル％のジルコニウムを含むことを特徴とする。[Means for Solving the Problems] In view of the above-mentioned problems, the inventors have discovered that the conventional problems can be solved by the novel catalyst described below, and have achieved the present invention. That is, in the exhaust gas purifying catalyst of the present invention, the catalyst coat layer is an oxide powder produced using a precipitation reaction from an aqueous solution containing rhodium, rhodium, platinum or palladium, and at least cerium and zirconium ions; In a monolithic exhaust gas purifying catalyst comprising activated alumina, the oxide powder containing at least cerium and zirconium contains cerium of 10 to 30 mol% in terms of metal, and
It is characterized by containing ~90 mol% zirconium.
【０００５】本発明で用いられる該少くともセリウムと
ジルコニウムを含む酸化物は、排ガス浄化用触媒に使用
される貴金属のうち特にロジウムの触媒性能向上に大き
く寄与する。ここで、セリウムとジルコニウムを含む酸
化物の少くとも１部は、ジルコニウムを主成分とした複
合酸化物であることをＸＲＤ回折し、確認している。[0005] The oxide containing at least cerium and zirconium used in the present invention greatly contributes to improving the catalytic performance of rhodium, among the noble metals used in exhaust gas purification catalysts. Here, it has been confirmed by XRD diffraction that at least a part of the oxide containing cerium and zirconium is a composite oxide containing zirconium as a main component.
【０００６】本発明で用いられるセリウムとジルコニウ
ムを含む酸化物粉末は、例えば硝酸セリウムと硝酸ジル
コニルの混合水溶液等セリウム、ジルコニウムのイオン
を含む酸性溶液に、アンモニア、尿素等を添加し、必要
に応じて加熱、加圧し、水酸化物等の沈澱を生成させ、
得られた沈澱物を乾燥、焼成することによって製造する
ことができる。この酸化物粉末は含有する金属種として
セリウム、ジルコニウムのみから成るもので十分な触媒
性能向上効果が得られるが、セリウム源としてセリウム
を主成分とし、他の希土類（例えばＬａ、Ｎｄ、Ｐｒ、
Ｙ）をも同時に含む低濃度のセリウム塩を用いてもよい
。The oxide powder containing cerium and zirconium used in the present invention is produced by adding ammonia, urea, etc. to an acidic solution containing cerium and zirconium ions, such as a mixed aqueous solution of cerium nitrate and zirconyl nitrate, as needed. heating and pressurizing to generate precipitates such as hydroxides,
It can be produced by drying and calcining the obtained precipitate. This oxide powder is composed only of cerium and zirconium as metal species and can sufficiently improve the catalytic performance.
A low concentration cerium salt containing Y) may also be used.
【０００７】上記酸化物粉末を用いた本発明の触媒の製
造方法としては、例えば活性アルミナ粉末と、少くとも
該セリウムとジルコニウムを含む酸化物粉末を湿式にて
混合して水性スラリーを調整し、セラミック製または金
属製のモノリス担体に塗布し、乾燥、焼成後さらにロジ
ウム或いはロジウムと白金またはパラジウムから成る貴
金属を含む水溶液に浸漬し、再び乾燥、焼成を行なうこ
とによって目的の触媒を得る方法がある。また、別の触
媒製造法の例としては、予め貴金属を担持したアルミナ
粉末と該セリウムとジルコニウムを含む酸化物粉末と湿
式にて混合して水溶性スラリーを調整し、セラミック製
または金属製のモノリス担体に塗布し、乾燥、焼成する
方法がある。[0007] A method for producing the catalyst of the present invention using the above oxide powder includes, for example, mixing activated alumina powder and the oxide powder containing at least cerium and zirconium in a wet manner to prepare an aqueous slurry; There is a method of obtaining the desired catalyst by coating it on a ceramic or metal monolithic carrier, drying and firing, then immersing it in an aqueous solution containing rhodium or a noble metal consisting of rhodium and platinum or palladium, and drying and firing again. . In addition, as an example of another catalyst manufacturing method, a water-soluble slurry is prepared by wet-mixing alumina powder supporting a noble metal with the oxide powder containing cerium and zirconium, and then a ceramic or metal monolith is prepared. There is a method in which it is applied to a carrier, dried, and fired.
【０００８】これらいずれの触媒製造工程においても、
用いられるウォッシュコートスラリー中に少くともセリ
ウムとジルコニウムを含む酸化物粉末を添加する工程が
含まれることによって、得られる触媒は、本発明の目的
に合致した優れた排ガス浄化性能を有するものとなる。[0008] In any of these catalyst manufacturing processes,
By including the step of adding an oxide powder containing at least cerium and zirconium to the washcoat slurry used, the resulting catalyst has excellent exhaust gas purification performance that meets the objective of the present invention.
【０００９】本発明で用いられる少くともセリウムとジ
ルコニウムを含む酸化物粉末の組成としては、セリウム
金属の含有量が１０〜３０モル％で、残部がジルコニウ
ムを主成分とすることが好ましい。セリウム含有量が１
０モル％未満ではセリウム、ジルコニウムの複合酸化物
生成量が充分とならず、セリウム含有量が３０モル％よ
り多くなるとセリウムが固溶しきれずＣｅＯ２が生成し
、充分な触媒性能向上が得られなくなる。[0009] As for the composition of the oxide powder containing at least cerium and zirconium used in the present invention, it is preferable that the content of cerium metal is 10 to 30 mol %, and the balance is mainly composed of zirconium. Cerium content is 1
If it is less than 0 mol%, the amount of composite oxide of cerium and zirconium produced will not be sufficient, and if the cerium content is more than 30 mol%, cerium will not be completely dissolved and CeO2 will be produced, making it impossible to obtain a sufficient improvement in catalyst performance. .
【００１０】また、本発明で用いられる少くともセリウ
ムとジルコニウムを含む酸化物粉末の触媒への添加量と
しては、触媒容量１Ｌ当り２０〜１００ｇで、かつモノ
リス担体に塗布される触媒層固形分中５〜６０重量％で
あることが好ましい。添加量がこれより少い場合は、添
加効果は認められるものの、ロジウムとの接触が充分で
ないためロジウムとの相互作用が小さくなり、本発明に
よる触媒性能上の優位性は充分に発揮されない。また、
添加量が上記数値より多い場合には、有意な添加量増量
効果はみられない。[0010] Furthermore, the amount of the oxide powder containing at least cerium and zirconium used in the present invention to be added to the catalyst is 20 to 100 g per liter of catalyst volume, and the amount is in the solid content of the catalyst layer coated on the monolithic carrier. It is preferably 5 to 60% by weight. If the amount added is less than this, although the addition effect is observed, the interaction with rhodium is insufficient because the contact with rhodium is insufficient, and the superiority of the catalyst performance of the present invention is not fully exhibited. Also,
When the amount added is larger than the above value, no significant effect of increasing the amount added is observed.
【００１１】[0011]
【作用】本発明の排ガス浄化用触媒に用いるセリウムと
ジルコニウムを含む酸化物粉末は、少くとも一部がジル
コニウムを主成分とする複合酸化物として存在している
。このセリウムとジルコニウムを含む酸化物粉末をロジ
ウムを含むコート層中に添加することにより、ロジウム
の持つ触媒作用が向上しその結果排ガス浄化作用が向上
する。その機構はまだ明らかとなっていないが、複合化
により酸化セリウム、酸化ジルコニウム単独では得られ
ないＯ２ストレージ能が発現することが判った。[Operation] At least a portion of the oxide powder containing cerium and zirconium used in the exhaust gas purifying catalyst of the present invention exists as a composite oxide containing zirconium as a main component. By adding this oxide powder containing cerium and zirconium to the coating layer containing rhodium, the catalytic action of rhodium is improved, and as a result, the exhaust gas purification action is improved. Although the mechanism has not yet been clarified, it has been found that by combining cerium oxide and zirconium oxide, an O2 storage ability that cannot be obtained alone is exhibited.
【００１２】表１に、下記反応条件でＯ２パルス法によ
り、本発明で用いられるセリウムとジルコニウムを含む
酸化物粉末（実施例２で用いたもの）、酸化セリウム粉
末、酸化ジルコニウム粉末につき、それぞれの酸素吸収
量を測定した結果を示す。
反応条件：Ｈ２還元 ５００℃、２時間Ｏ２パルス温
度 ２０℃
触媒量 ０．２ ｇTable 1 shows that the oxide powder containing cerium and zirconium used in the present invention (used in Example 2), the cerium oxide powder, and the zirconium oxide powder were prepared using the O2 pulse method under the following reaction conditions. The results of measuring the amount of oxygen absorbed are shown. Reaction conditions: H2 reduction 500°C, 2 hours O2 pulse temperature 20°C Catalyst amount 0.2 g
【００１３】表１より明らかなように、本発明で用いら
れるセリウムとジルコニウムを含む酸化物粉末は、酸化
セリウム粉末、酸化ジルコニウム粉末に比較し優れた酸
素吸収能力を示す。酸素吸収能力が向上することにより
、例えば排ガス雰囲気が酸素過剰の状態でも酸素を吸収
し排ガス浄化に適した酸素濃度に保つことが可能となる
。また、貴金属の酸化状態を排ガス浄化に適した状態に
保つ可能性もある。As is clear from Table 1, the oxide powder containing cerium and zirconium used in the present invention exhibits superior oxygen absorption ability compared to cerium oxide powder and zirconium oxide powder. By improving the oxygen absorption capacity, it becomes possible to absorb oxygen and maintain an oxygen concentration suitable for exhaust gas purification, for example, even when the exhaust gas atmosphere is in an oxygen-excess state. It also has the potential to maintain the oxidation state of precious metals in a state suitable for exhaust gas purification.
【００１４】さらに本法では、コートスラリー調整時の
配合比あるいは、スラリー塗布量によってセリウムとジ
ルコニウムを含む酸化物量を調整することが容易であり
、自動車排ガスなど排ガス組成が酸素雰囲気と還元雰囲
気との間で変動する場合に、その使用条件に応じて添加
量を調整することが可能となっている。Furthermore, in this method, it is easy to adjust the amount of oxides containing cerium and zirconium by changing the mixing ratio when preparing the coating slurry or the amount of slurry applied, and the composition of exhaust gas such as automobile exhaust gas is different between oxygen atmosphere and reducing atmosphere. The amount added can be adjusted depending on the conditions of use.
【００１５】この様な作用効果により、本発明の排ガス
浄化用触媒は優れた排ガス浄化作用を持つ。Due to these effects, the exhaust gas purifying catalyst of the present invention has an excellent exhaust gas purifying effect.
【００１６】[0016]
【実施例】以下、本発明を実施例、比較例および試験例
により説明する。[Examples] The present invention will be explained below with reference to Examples, Comparative Examples, and Test Examples.
【００１７】実施例１
セリウム塩とジルコニウム塩の混合水溶液にアンモニア
水溶液を徐々に加え、生じた沈澱を濾過し焼成してセリ
ウムとジルコニウムを含む酸化物粉末を得た（Ｃｅ／Ｚ
ｒ比＝１／９）。また、あらかじめＺｒを３重量％担持
し焼成した活性アルミナ粉末に硝酸ロジウム水溶液を噴
霧し焼成してロジウム担持アルミナ粉末を得た（Ｒｈ
１．５重量％）。上記酸化物粉末４５０ｇ、ロジウム担
持アルミナ粉末４５０ｇ及び酢酸１０重量％水溶液９０
０ｇとを磁性ボールミルに投入し、混合粉砕してスラリ
ー液を得た。このスラリー液をコーディライト質モノリ
ス担体（１．３ Ｌ）に噴霧し、空気流にてセル内の余
剰のスラリーを取り除いて乾燥し、４００ ℃で１時間
焼成してコート層重量 ８０ｇ／Ｌ −担体の（触媒−
１）を得た。Example 1 An ammonia aqueous solution was gradually added to a mixed aqueous solution of a cerium salt and a zirconium salt, and the resulting precipitate was filtered and calcined to obtain an oxide powder containing cerium and zirconium (Ce/Z).
r ratio = 1/9). In addition, a rhodium nitrate aqueous solution was sprayed onto activated alumina powder, which had previously been loaded with 3% by weight of Zr and fired, and then fired to obtain a rhodium-supported alumina powder (Rh
1.5% by weight). 450 g of the above oxide powder, 450 g of rhodium-supported alumina powder, and 90 g of a 10% aqueous acetic acid solution
0 g was put into a magnetic ball mill, mixed and pulverized to obtain a slurry liquid. This slurry liquid was sprayed onto a corderitic monolithic support (1.3 L), the excess slurry inside the cells was removed using an air stream, the slurry was dried, and the coating layer was baked at 400 °C for 1 hour to give a coating layer weight of 80 g/L. of the carrier (catalyst)
1) was obtained.
【００１８】実施例２
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末のＣｅ／Ｚｒ比２／８としたものを用いた以外は実
施例１と同様の方法で（触媒−２）を得た。Example 2 Catalyst-2 was obtained in the same manner as in Example 1 except that the oxide powder containing cerium and zirconium in Example 1 with a Ce/Zr ratio of 2/8 was used. .
【００１９】実施例３
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末のＣｅ／Ｚｒ比を３／７としたものを用いた以外は
実施例１と同様の方法で（触媒−３）を得た。Example 3 Catalyst-3 was obtained in the same manner as in Example 1 except that the oxide powder containing cerium and zirconium in Example 1 with a Ce/Zr ratio of 3/7 was used. Ta.
【００２０】比較例１
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末のＣｅ／Ｚｒ比４／６としたものを用いた以外は実
施例１と同様の方法で（触媒−４）を得た。Comparative Example 1 Catalyst-4 was obtained in the same manner as in Example 1 except that the oxide powder containing cerium and zirconium in Example 1 with a Ce/Zr ratio of 4/6 was used. .
【００２１】比較例２
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末の代わりに酸化ジルコニウムを用いた以外は実施例
１と同様の方法で（触媒−５）を得た。Comparative Example 2 A catalyst (Catalyst-5) was obtained in the same manner as in Example 1 except that zirconium oxide was used instead of the oxide powder containing cerium and zirconium in Example 1.
【００２２】比較例３
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末の代わりに酸化セリウムを用いた以外は実施例１と
同様の方法で（触媒−６）を得た。Comparative Example 3 Catalyst-6 was obtained in the same manner as in Example 1, except that cerium oxide was used instead of the cerium- and zirconium-containing oxide powder in Example 1.
【００２３】比較例４
実施例１におけるセリウムとジルコニウムを含む酸化物
粉末の代わりに酸化ジルコニウムに硝酸セリウム水溶液
をＣｅ／Ｚｒ比＝１／９となるよう含浸担持し、６５０
℃で１時間焼成したものを用いた以外は実施例１と同
様の方法で（触媒−７）を得た。Comparative Example 4 Instead of the oxide powder containing cerium and zirconium in Example 1, cerium nitrate aqueous solution was impregnated and supported on zirconium oxide so that the Ce/Zr ratio was 1/9.
Catalyst-7 was obtained in the same manner as in Example 1, except that the catalyst was calcined at ℃ for 1 hour.
【００２４】実施例４
実施例１と同様の製法でＲｈを１．０ 重量％担持した
ロジウム担持アルミナ粉末を得た。またあらかじめＣｅ
を８重量％、Ｚｒを４重量％、Ｂａを４重量％担持し焼
成したアルミナ粉末を得、これを攪拌しながら硝酸パラ
ジウム水溶液を噴霧し、その後焼成してＰｄを１．０７
重量％担持したパラジウム１．０７重量％担持アルミナ
粉末を得た。さらに同様の方法でパラジウム１．１９重
量％パラジウム担持アルミナを得た。また硝酸ジルコニ
ウムと硝酸セリウムを含む水溶液にアンモニア水溶液を
添加し、生成した沈澱物を焼成して、ＺｒＯ２を１０重
量％含むジルコニア１０重量％−セリウム酸化物を得た
。上記パラジウム１．１９％担持アルミナ粉末７７２ｇ
、上記ジルコニア１０重量％−セリウム酸化物４２８ｇ
、酢酸１０重量％水溶液１２００ｇ を実施例１と同様
の方法でモノリス担体（１．７ Ｌ）に担持し、コート
層重量１４０ｇ／ Ｌ−担体を得た。さらに上記ロジウ
ム担持アルミナ粉末１１４ｇ、上記パラジウム１．０７
重量％担持アルミナ３０６ｇ、実施例２と同様のセリウ
ムとジルコニウムを含む酸化物粉末４８０ｇ、酢酸１０
重量％水溶液９００ｇを実施例１と同様の方法で上記コ
ート層重量１４０ｇ／ Ｌ−担体に担持し、コート層重
量合計２１０ｇ／ Ｌ−担体の（触媒−８）を得た。Example 4 Rhodium-supported alumina powder supporting 1.0% by weight of Rh was obtained by the same manufacturing method as in Example 1. Also, in advance Ce
A fired alumina powder supporting 8% by weight of Zr, 4% by weight of Zr, and 4% by weight of Ba was obtained, which was sprayed with an aqueous solution of palladium nitrate while stirring, and then fired to reduce Pd to 1.07% by weight.
An alumina powder carrying 1.07% by weight of palladium was obtained. Furthermore, palladium-supported alumina with 1.19% by weight of palladium was obtained in the same manner. Further, an ammonia aqueous solution was added to an aqueous solution containing zirconium nitrate and cerium nitrate, and the resulting precipitate was calcined to obtain a 10% by weight zirconia-cerium oxide containing 10% by weight of ZrO2. 772g of the above palladium 1.19% supported alumina powder
, 10% by weight of the above zirconia - 428g of cerium oxide
, 1200 g of a 10% by weight aqueous acetic acid solution was supported on a monolithic carrier (1.7 L) in the same manner as in Example 1 to obtain a coating layer weight of 140 g/L-carrier. Furthermore, 114 g of the above rhodium-supported alumina powder, 1.07 g of the above palladium
306 g of alumina supported by weight%, 480 g of oxide powder containing cerium and zirconium similar to Example 2, 10 acetic acid
900 g of the wt% aqueous solution was supported on the L-carrier with a coat layer weight of 140 g in the same manner as in Example 1 to obtain (Catalyst-8) with a total coat layer weight of 210 g/L-carrier.
【００２５】比較例５
実施例５におけるセリウムとジルコニウムを含む酸化物
の代わりに比較例３と同様のセリウム、ジルコニウム酸
化物を用いた以外は実施例５と同様の方法で（触媒−９
）を得た。Comparative Example 5 The same method as in Example 5 was used except that the same cerium and zirconium oxides as in Comparative Example 3 were used instead of the oxides containing cerium and zirconium in Example 5 (catalyst-9).
) was obtained.
【００２６】実施例５
実施例１と同様の方法でＲｈを１．０ 重量％担持した
ロジウム担体アルミナ粉末を得た。また、あらかじめＣ
ｅを８重量％、Ｚｒを４重量％、Ｌａを４重量％担持し
焼成して得たＣｅ−Ｚｒ−Ｌａ−アルミナ粉末を得、こ
れを攪拌しながら硝酸パラジウム水溶液を噴霧し、その
後焼成してＰｄを１．１６重量％担持したパラジウム担
体アルミナ粉末を得た。上記パラジウム担持アルミナ粉
末７７２ｇ、実施例５と同様のジルコニア１０重量％−
セリウム酸化物４２８ｇ、硝酸酸性アルミナゾル１２０
０ｇ を実施例１と同様の方法で担持し、コート層重量
１４２ｇ／Ｌ−担体を得た。さらに上記ロジウム担持ア
ルミナ粉末１１４ｇ、上記パラジウム担持アルミナ粉末
２７９ｇ、実施例２と同様のセリウムとジルコニウムを
含む酸化物粉末３８０ｇ、上記Ｃｅ−Ｚｒ−Ｌａ−アル
ミナ粉末８９ｇ 、硝酸酸性アルミナゾル９００ｇを、
実施例１と同様の方法で上記コート層重量１４２ｇ／
Ｌ−担体に担持し、コート層重量合計２１３ｇ／ Ｌ−
担体の（触媒−１０） を得た。Example 5 A rhodium-supported alumina powder carrying 1.0% by weight of Rh was obtained in the same manner as in Example 1. Also, in advance, C
A Ce-Zr-La-alumina powder was obtained by carrying 8% by weight of E, 4% by weight of Zr, and 4% by weight of La, and then spraying an aqueous solution of palladium nitrate while stirring the powder, followed by baking. A palladium-supported alumina powder carrying 1.16% by weight of Pd was obtained. 772 g of the above palladium-supported alumina powder, 10% by weight of zirconia similar to Example 5.
Cerium oxide 428g, nitric acid acidic alumina sol 120g
0 g was supported in the same manner as in Example 1 to obtain a coat layer weight of 142 g/L-carrier. Furthermore, 114 g of the above rhodium-supported alumina powder, 279 g of the above palladium-supported alumina powder, 380 g of the oxide powder containing cerium and zirconium similar to Example 2, 89 g of the above Ce-Zr-La-alumina powder, and 900 g of the nitric acid acidic alumina sol,
In the same manner as in Example 1, the weight of the coating layer was 142 g/
Supported on L-carrier, total coating layer weight 213g/L-
A carrier (catalyst-10) was obtained.
【００２７】比較例６
実施例６におけるセリウムとジルコニウムを含む酸化物
粉末を２５４ｇ、Ｃｅ−Ｚｒ−Ｌａ−アルミナ粉末を２
１５ｇとした以外は実施例６と同様の方法で触媒を調整
し、（触媒−１１） を得た。Comparative Example 6 254 g of oxide powder containing cerium and zirconium and 2 g of Ce-Zr-La-alumina powder in Example 6 were used.
A catalyst was prepared in the same manner as in Example 6, except that the amount was changed to 15 g, and (Catalyst-11) was obtained.
【００２８】比較例７
実施例６におけるセリウムとジルコニウムを含む酸化物
粉末を１２７ｇ、Ｃｅ−Ｚｒ−Ｌａ−アルミナ粉末を３
４２ｇとした以外は実施例６と同様の方法で触媒を調整
し、（触媒−１２） を得た。Comparative Example 7 127 g of oxide powder containing cerium and zirconium in Example 6 and 3 g of Ce-Zr-La-alumina powder were used.
A catalyst was prepared in the same manner as in Example 6 except that the amount was changed to 42 g, and (Catalyst-12) was obtained.
【００２９】実施例６
実施例１と同様の方法でＲｈを２．２５３ 重量％担持
したロジウム担持アルミナ粉末を得た。また、あらかじ
めＣｅを３重量％担持し焼成したＣｅ−アルミナ粉末を
得、これを攪拌しながらジニトロジアンミン白金酸水溶
液を噴霧し、その後焼成してＰｔを１．１ 重量％担持
した白金担持アルミナ粉末を得た。上記白金担持アルミ
ナ粉末６１１ｇ、実施例５と同様のジルコニア１０重量
％−セリウム酸化物４５３ｇ、上記Ｃｅ−アルミナ粉末
４３ｇ 、硝酸酸性アルミナゾル１２００ｇ を実施例
１と同様の方法で担持し、コート層重量２１０ｇ／ Ｌ
−担体を得た。さらに上記ロジウム担持アルミナ粉末１
７２ｇ、上記Ｃｅ−アルミナ粉末３３１ｇ、実施例２と
同様のセリウムとジルコニウムを含む酸化物粉末３２７
ｇ、硝酸酸性アルミナゾル９００ｇを実施例１と同様の
方法で上記コート層重量２１０ｇ／ Ｌ担体に担持し、
コート層重量合計２６５ｇ／ Ｌ−担体の（触媒−１３
） を得た。Example 6 A rhodium-supported alumina powder carrying 2.253% by weight of Rh was obtained in the same manner as in Example 1. In addition, we obtained a Ce-alumina powder that had previously carried 3% by weight of Ce and fired it, and sprayed it with an aqueous solution of dinitrodiammine platinum acid while stirring, and then fired it to obtain a platinum-supported alumina powder that supported 1.1% by weight of Pt. I got it. 611 g of the above platinum-supported alumina powder, 453 g of the same zirconia 10% by weight-cerium oxide as in Example 5, 43 g of the above Ce-alumina powder, and 1200 g of nitric acid acidic alumina sol were supported in the same manner as in Example 1, and the coating layer weight was 210 g. / L
- A carrier was obtained. Furthermore, the above rhodium-supported alumina powder 1
72 g, 331 g of the above Ce-alumina powder, 327 oxide powder containing cerium and zirconium similar to Example 2
g, 900 g of nitric acid acidic alumina sol was supported on the above coating layer weight 210 g/L carrier in the same manner as in Example 1,
Coat layer total weight 265g/L-carrier (catalyst-13
) obtained.
【００３０】比較例８
実施例７におけるセリウムとジルコニウムを含む酸化物
粉末の代わりに実施例５と同様のジルコニウム１０重量
％−セリウム酸化物を用いた以外は実施例７と同様の方
法で（触媒−１４） を得た。Comparative Example 8 The same method as in Example 7 was used except that 10% by weight of zirconium-cerium oxide as in Example 5 was used instead of the oxide powder containing cerium and zirconium in Example 7. -14) was obtained.
【００３１】試験例１
実施例１〜３および５、比較例１〜４および６〜７の各
触媒（触媒１〜７および１０〜１２） につき、下記条
件でエンジン耐久を行った後の性能評価を行い、耐久劣
化触媒のＨＣ、ＣＯ、ＮＯｘ 浄化率を測定した。
触媒性能評価結果を表２に示す。
＜エンジン耐久条件＞
触媒入口排ガス温度
８５０ ℃ 耐久時間
５０ 時間 エンジ
ン
排気量 ４４００ ＣＣ 燃料
無
鉛ガソリン 耐久中入口エミッション
ＣＯ ０．４〜 ０．６％
Ｏ２ ０．５± ０．１％
ＮＯ 約１０００ ｐｐｍ
ＨＣ 約２５００ ｐｐｍ
ＣＯ２ １４．９± ０．
１％＜性能評価条件＞
触媒入口排ガス温度
４００ ℃ エンジン
排気量 ４４００ Ｃ
Ｃ 燃料
無鉛ガソリン 平均空燃比（
制御中心値） １４．６Test Example 1 Performance evaluation of each catalyst of Examples 1 to 3 and 5 and Comparative Examples 1 to 4 and 6 to 7 (catalysts 1 to 7 and 10 to 12) after engine durability was performed under the following conditions. The HC, CO, and NOx purification rates of the durable deteriorated catalyst were measured. Table 2 shows the catalyst performance evaluation results. <Engine durability conditions> Catalyst inlet exhaust gas temperature
850℃ durability time
50 hours engine
Displacement 4400 CC Fuel
Unleaded gasoline Endurance medium inlet emissions
CO 0.4-0.6%
O2 0.5± 0.1%
NO approx. 1000 ppm
HC approx. 2500 ppm
CO2 14.9±0.
1% <Performance evaluation conditions> Catalyst inlet exhaust gas temperature
400℃ engine
Displacement 4400C
C Fuel
Unleaded gasoline average air-fuel ratio (
control center value) 14.6
【００３２
】試験例２
実施例４および比較例５の触媒（触媒８〜９）につき触
媒入口ガス温度を７５０℃、耐久時間を １００時間と
した以外は試験例１の場合と同じ条件でエンジン耐久を
行った後の性能評価を行い、耐久劣化触媒のＨＣ、ＣＯ
、ＮＯｘ 浄化率を測定した。触媒性能評価結果を表２
に示す。
試験例３
実施例６および比較例８の触媒（触媒１３〜１４） に
つき、触媒入口ガス温度を９００ ℃、燃料を有鉛ガソ
リンとした以外は試験例１の場合と同じ条件でエンジン
耐久を行った後の性能評価を行い、耐久劣化触媒のＨＣ
、ＣＯ、ＮＯｘ 浄化率を測定した。触媒評価結果を表
２に示す。0032
Test Example 2 Engine durability was conducted under the same conditions as in Test Example 1, except that the catalysts of Example 4 and Comparative Example 5 (catalysts 8 to 9) had a catalyst inlet gas temperature of 750°C and an endurance time of 100 hours. The performance of the catalyst after deterioration was evaluated, and the HC and CO
, NOx purification rate was measured. Table 2 shows the catalyst performance evaluation results.
Shown below. Test Example 3 Engine durability was conducted for the catalysts of Example 6 and Comparative Example 8 (catalysts 13 to 14) under the same conditions as in Test Example 1, except that the catalyst inlet gas temperature was 900 °C and the fuel was leaded gasoline. We evaluated the performance of the catalyst after deterioration, and
, CO, and NOx purification rates were measured. Table 2 shows the catalyst evaluation results.
【００３３】[0033]
【表２】[Table 2]
【００３４】[0034]
【発明の効果】以上説明してきたようにこの発明によれ
ば、少くともセリウムとジルコニウムのイオンを含む水
溶液から沈澱生成反応を用いて製造されたセリウムとジ
ルコニウムを含む酸化物粉末をロジウムを含むコート層
中に添加することにより、他のセリウムおよびジルコニ
ウム酸化物の添加に比べ、高温耐久後の排ガス浄化性能
において明らかに優れた触媒性能が得られる。これは実
施例からわかるように、排ガス浄化用触媒に用いられた
セリウムとジルコニウムを含む酸化物が、その少くとも
一部がジルコニウムを主成分とし複合化している効果に
よるものであることは明らかである。さらに、本発明の
効果はセリウムとジルコニウムを含む酸化物の添加量が
比較的大きい場合に顕著であり、またセリウムとジルコ
ニウムの比率に好適な範囲が存在する。As explained above, according to the present invention, an oxide powder containing cerium and zirconium produced by a precipitation reaction from an aqueous solution containing at least cerium and zirconium ions is coated with rhodium. By adding it to the layer, compared to the addition of other cerium and zirconium oxides, clearly superior catalyst performance in exhaust gas purification performance after high-temperature durability can be obtained. As can be seen from the examples, it is clear that this is due to the fact that the oxide containing cerium and zirconium used in the exhaust gas purification catalyst is at least partially composed of zirconium as its main component. be. Furthermore, the effects of the present invention are remarkable when the amount of the oxide containing cerium and zirconium added is relatively large, and there is a suitable range for the ratio of cerium and zirconium.
Claims (3)
ムと白金またはパラジウムと、少くとも、セリウム、ジ
ルコニウムのイオンを含む水溶液から沈澱生成反応を用
いて製造された酸化物粉末と、活性アルミナとを含んで
なるモノリス型排ガス浄化用触媒において、該少くとも
セリウムとジルコニウムを含む酸化物粉末が金属換算で
１０〜３０モル％のセリウムと、７０〜９０モル％のジ
ルコニウムを含むことを特徴とする排ガス浄化用触媒。Claim 1: The catalyst coat layer contains rhodium or rhodium and platinum or palladium, an oxide powder produced by a precipitation reaction from an aqueous solution containing at least cerium and zirconium ions, and activated alumina. A monolithic exhaust gas purifying catalyst characterized in that the oxide powder containing at least cerium and zirconium contains 10 to 30 mol% of cerium and 70 to 90 mol% of zirconium in terms of metal. catalyst.
含む酸化物粉末がロジウムを含むコート層中に添加され
ていることを特徴とする請求項１記載の排ガス浄化用触
媒。2. The exhaust gas purifying catalyst according to claim 1, wherein the oxide powder containing at least cerium and zirconium is added to a coating layer containing rhodium.
含む酸化物粉末が触媒１Ｌ当り２０〜１００ｇ、かつ、
モノリス担体に塗布される触媒コート層固形分中５〜６
０重量％であることを特徴とする請求項１または２記載
の排ガス浄化用触媒。3. The oxide powder containing at least cerium and zirconium is present in an amount of 20 to 100 g per liter of catalyst, and
5 to 6 in the solid content of the catalyst coating layer applied to the monolithic carrier
The exhaust gas purifying catalyst according to claim 1 or 2, characterized in that the content is 0% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3133277A JP2734808B2 (en) | 1991-05-10 | 1991-05-10 | Exhaust gas purification catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3133277A JP2734808B2 (en) | 1991-05-10 | 1991-05-10 | Exhaust gas purification catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04334548A true JPH04334548A (en) | 1992-11-20 |
| JP2734808B2 JP2734808B2 (en) | 1998-04-02 |
Family
ID=15100879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3133277A Expired - Lifetime JP2734808B2 (en) | 1991-05-10 | 1991-05-10 | Exhaust gas purification catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2734808B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10286462A (en) * | 1997-04-11 | 1998-10-27 | Nissan Motor Co Ltd | Catalyst of purifying exhaust gas |
| JP2006326527A (en) * | 2005-05-27 | 2006-12-07 | Cataler Corp | Catalyst for exhaust gas purification |
| JP2007105632A (en) * | 2005-10-13 | 2007-04-26 | Nissan Motor Co Ltd | Exhaust gas cleaning catalyst |
| JP2011515220A (en) * | 2008-03-27 | 2011-05-19 | ユミコア・アクチエンゲゼルシャフト・ウント・コムパニー・コマンディットゲゼルシャフト | Base metal and base metal modified diesel oxidation catalyst |
| US8778831B2 (en) | 2008-03-27 | 2014-07-15 | Umicore Ag & Co. Kg | Base metal and base metal modified diesel oxidation catalysts |
| US9403151B2 (en) | 2009-01-30 | 2016-08-02 | Umicore Ag & Co. Kg | Basic exchange for enhanced redox OS materials for emission control applications |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63116741A (en) * | 1986-11-04 | 1988-05-21 | Toyota Motor Corp | Catalyst for purifying exhaust gas |
-
1991
- 1991-05-10 JP JP3133277A patent/JP2734808B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63116741A (en) * | 1986-11-04 | 1988-05-21 | Toyota Motor Corp | Catalyst for purifying exhaust gas |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10286462A (en) * | 1997-04-11 | 1998-10-27 | Nissan Motor Co Ltd | Catalyst of purifying exhaust gas |
| JP2006326527A (en) * | 2005-05-27 | 2006-12-07 | Cataler Corp | Catalyst for exhaust gas purification |
| JP4648089B2 (en) * | 2005-05-27 | 2011-03-09 | 株式会社キャタラー | Exhaust gas purification catalyst |
| JP2007105632A (en) * | 2005-10-13 | 2007-04-26 | Nissan Motor Co Ltd | Exhaust gas cleaning catalyst |
| JP2011515220A (en) * | 2008-03-27 | 2011-05-19 | ユミコア・アクチエンゲゼルシャフト・ウント・コムパニー・コマンディットゲゼルシャフト | Base metal and base metal modified diesel oxidation catalyst |
| US8778831B2 (en) | 2008-03-27 | 2014-07-15 | Umicore Ag & Co. Kg | Base metal and base metal modified diesel oxidation catalysts |
| US9403151B2 (en) | 2009-01-30 | 2016-08-02 | Umicore Ag & Co. Kg | Basic exchange for enhanced redox OS materials for emission control applications |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2734808B2 (en) | 1998-04-02 |
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