WO2010137657A1 - 排ガス浄化用触媒 - Google Patents
排ガス浄化用触媒 Download PDFInfo
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- WO2010137657A1 WO2010137657A1 PCT/JP2010/059016 JP2010059016W WO2010137657A1 WO 2010137657 A1 WO2010137657 A1 WO 2010137657A1 JP 2010059016 W JP2010059016 W JP 2010059016W WO 2010137657 A1 WO2010137657 A1 WO 2010137657A1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/024—Multiple impregnation or coating
- B01J37/0244—Coatings comprising several layers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
- B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
- B01D53/9445—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC]
- B01D53/945—Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC] characterised by a specific catalyst
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/56—Platinum group metals
- B01J23/58—Platinum group metals with alkali- or alkaline earth metals
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0215—Coating
- B01J37/0219—Coating the coating containing organic compounds
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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- B01D2255/00—Catalysts
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- B01D2255/102—Platinum group metals
- B01D2255/1021—Platinum
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- B01D2255/10—Noble metals or compounds thereof
- B01D2255/102—Platinum group metals
- B01D2255/1023—Palladium
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/10—Noble metals or compounds thereof
- B01D2255/102—Platinum group metals
- B01D2255/1025—Rhodium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/204—Alkaline earth metals
- B01D2255/2042—Barium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/206—Rare earth metals
- B01D2255/2065—Cerium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/20—Metals or compounds thereof
- B01D2255/207—Transition metals
- B01D2255/20715—Zirconium
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/40—Mixed oxides
- B01D2255/407—Zr-Ce mixed oxides
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2255/00—Catalysts
- B01D2255/90—Physical characteristics of catalysts
- B01D2255/902—Multilayered catalyst
- B01D2255/9022—Two layers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2370/00—Selection of materials for exhaust purification
- F01N2370/02—Selection of materials for exhaust purification used in catalytic reactors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2510/00—Surface coverings
- F01N2510/06—Surface coverings for exhaust purification, e.g. catalytic reaction
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2510/00—Surface coverings
- F01N2510/06—Surface coverings for exhaust purification, e.g. catalytic reaction
- F01N2510/068—Surface coverings for exhaust purification, e.g. catalytic reaction characterised by the distribution of the catalytic coatings
- F01N2510/0684—Surface coverings for exhaust purification, e.g. catalytic reaction characterised by the distribution of the catalytic coatings having more than one coating layer, e.g. multi-layered coatings
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Definitions
- the present invention relates to exhaust gas purification technology.
- Many exhaust gas purifying catalysts contain precious metals as catalytic metals.
- the noble metal plays a role of promoting the oxidation reaction of HC and CO and the reduction reaction of NO x .
- the exhaust gas purification catalyst containing a noble metal may have an insufficient NO x purification rate, particularly in a rich atmosphere where the HC concentration in the exhaust gas is high.
- An object of the present invention is to provide a technique capable of achieving further excellent exhaust gas purification performance.
- a ratio of a total mass of all alkaline earth metal elements contained in the first catalyst layer to a total mass of all noble metals contained in the first catalyst layer is a third value; Between the first catalyst layer A second catalyst layer facing the substrate or interposed between the substrate and the first catalyst layer, wherein the second catalyst layer contains rhodium and an alkaline earth metal element. A ratio of the mass of rhodium contained in the second catalyst layer to the total mass of all the noble metals contained in the second catalyst layer is greater than the second value.
- the layer does not contain palladium and platinum, or the ratio of the total mass of palladium and platinum contained in the noble metal to the total mass of all noble metals contained in the second catalyst layer is less than the first value.
- the ratio of the total mass of all alkaline earth metal elements contained in the second catalyst layer to the total mass of all precious metals contained in the second catalyst layer further includes at least one of palladium and platinum so as to be small. 3 for purification of exhaust gas was and a smaller second catalytic layer than value catalyst.
- FIG. 1 is a cross-sectional view schematically showing an exhaust gas purifying catalyst according to one embodiment of the present invention.
- Sectional drawing which shows schematically the catalyst for exhaust gas purification which concerns on one modification.
- the graph which shows an example of the relationship between ratio R and NOx discharge
- composite oxide here means that a plurality of oxides are not simply physically mixed but a plurality of oxides form a solid solution.
- alkaline earth metal element includes beryllium and magnesium.
- FIG. 1 is a cross-sectional view schematically showing an exhaust gas purifying catalyst according to one embodiment of the present invention.
- the exhaust gas-purifying catalyst 1 includes a base material 10 and a catalyst layer 20.
- the catalyst layer 20 includes a first catalyst layer 20A formed on the substrate 10 and a second catalyst layer 20B formed on the first catalyst layer 20A.
- the first catalyst layer 20A contains at least one of palladium and platinum as a noble metal.
- the first catalyst layer 20A may further contain a noble metal other than palladium and platinum.
- the first catalyst layer 20A may further contain rhodium as a noble metal.
- the first catalyst layer 20A contains only at least one of palladium and platinum as a noble metal.
- the noble metal contained in the first catalyst layer 20A is typically supported on alumina doped with an alkaline earth metal element. This noble metal plays a role of catalyzing, for example, the oxidation reaction of HC and CO and the reduction reaction of NO x .
- the alkaline earth metal element doped in alumina has a role of suppressing HC poisoning of the noble metal contained in the first catalyst layer 20A.
- the alkaline earth metal element for example, barium, calcium, strontium, beryllium, magnesium, or a combination of two or more thereof is used.
- barium is used as the alkaline earth metal element.
- the amount of the alkaline earth metal element doped into the alumina is, for example, in the range of 0.1% by mass to 20% by mass with respect to the mass of the alumina, and typically 1% by mass to Within the range of 10% by mass. If this amount is too small, there is a possibility that suppression of precious metal HC poisoning will be insufficient. When this amount is excessively large, the heat resistance of the alumina is lowered, the agglomeration of noble metals is likely to occur, and the exhaust gas purification performance of the exhaust gas purification catalyst 1 may be lowered.
- the content of the first alkaline earth metal element per unit volume of the base material 10 in the first catalyst layer 20A is, for example, 0.1 g / L or more, and typically 1 g / L or more. Moreover, this content shall be 50 g / L or less, for example, typically 20 g / L or less. If this content is excessively reduced or excessively increased, the exhaust gas purification performance of the exhaust gas purification catalyst 1 may be deteriorated.
- the second catalyst layer 20B faces the substrate 10 with the first catalyst layer 20A interposed therebetween.
- the second catalyst layer 20B contains rhodium and alumina doped with an alkaline earth metal element.
- the second catalyst layer 20B may further contain a precious metal other than rhodium.
- the second catalyst layer 20B may further include at least one of palladium and platinum as a noble metal.
- the ratio of the total mass of palladium and platinum contained in the second catalyst layer 20B to the total mass of all precious metals contained in the second catalyst layer 20B is smaller than that in the first catalyst layer 20A.
- the second catalyst layer 20B typically contains only rhodium as a noble metal, or contains only rhodium and platinum.
- the noble metal contained in the second catalyst layer 20B is typically supported on alumina doped with an alkaline earth metal element. This noble metal plays a role of catalyzing, for example, the oxidation reaction of HC and CO and the reduction reaction of NO x .
- the alkaline earth metal element doped in alumina has a role of suppressing HC poisoning of the noble metal contained in the second catalyst layer 20B.
- the alkaline earth metal element for example, barium, calcium, strontium, beryllium, magnesium, or a combination of two or more thereof is used.
- barium is used as the alkaline earth metal element.
- the alkaline earth metal element contained in the second catalyst layer 20B may be the same as or different from the alkaline earth metal element contained in the first catalyst layer 20A.
- the amount of the alkaline earth metal element doped into alumina is, for example, in the range of 0.1% by mass to 20% by mass, typically 1% by mass to Within the range of 10% by mass. If this amount is too small, there is a possibility that suppression of precious metal HC poisoning will be insufficient. If this amount is excessively large, the heat resistance of the alumina is reduced, the agglomeration of noble metals is likely to occur, and the exhaust gas purification performance of the exhaust gas purification catalyst 1 may be reduced.
- the ratio of the total mass of all alkaline earth metal elements contained in the second catalyst layer 20B to the total mass of noble metals (hereinafter also referred to as the second mass ratio) is the sum of all noble metals contained in the first catalyst layer 20A. It is smaller than the ratio of the total mass of all alkaline earth metal elements contained in the first catalyst layer 20A to the mass (hereinafter also referred to as the first mass ratio).
- the ratio R of the second mass ratio to the first mass ratio is, for example, 0.95 or less, typically 0.9 or less.
- the ratio R is typically 0.001 or more. If the ratio R is excessively increased or excessively decreased, the exhaust gas purification performance of the exhaust gas purification catalyst 1 may be deteriorated.
- the content of the second alkaline earth metal element per unit volume of the base material 10 in the second catalyst layer 20B is, for example, 0.05 g / L or more, and typically 0.5 g / L or more. Moreover, this content shall be 10 g / L or less, for example, typically 5 g / L or less. If this content is excessively reduced or excessively increased, the exhaust gas purification performance of the exhaust gas purification catalyst 1 may be deteriorated.
- alumina doped with an alkaline earth metal element is used as a material for both of the catalyst layers 20A and 20B.
- an alkaline earth metal element is added in the form of a salt.
- the contact between the catalyst metal supported on the alumina and the alkaline earth metal element is relatively difficult to occur. . That is, some of the alkaline earth metal elements are in contact with the catalyst metal, but the other part of the alkaline earth metal element is not in contact with the catalyst metal. And the alkaline-earth metal element which does not contact with a catalyst metal does not contribute to suppression of HC poisoning of a catalyst metal. Therefore, when there are many such alkaline earth metal elements, it may be difficult to improve the exhaust gas purification performance of the catalyst.
- the alkaline earth metal element when alumina doped with an alkaline earth metal element is used as the material of the catalyst layers 20A and 20B, the alkaline earth metal element can be distributed with high uniformity in the structure of the alumina.
- the alkaline earth metal element doped in alumina and the catalyst metal supported on the alumina are present close to each other. That is, in this case, the contact between the alkaline earth metal element and the catalyst metal is likely to occur as compared with the case where a mixture of alumina and a salt of the alkaline earth metal element is used. Therefore, in this case, HC poisoning of the catalyst metal can be more efficiently suppressed. Therefore, when using alumina doped with an alkaline earth metal element, excellent exhaust gas purification performance can be achieved.
- alumina doped with an alkaline earth metal element is prepared, for example, as follows. That is, first, a mixed aqueous solution containing aluminum nitrate, an alkaline earth metal element carbonate and citric acid is prepared. Next, hydrazine is added to the mixed aqueous solution. Thereafter, the reaction system is heated and stirred to obtain a precipitate. The precipitate is filtered off and the resulting filter cake is dried. Next, the obtained solid is fired. In this way, alumina doped with an alkaline earth metal element is obtained.
- the uniformity of the alkaline earth metal element distribution in each of the first catalyst layer 20A and the second catalyst layer 20B is evaluated as follows.
- C Al, AE is the covariance between the intensity I Al, i and the intensity I AE, i
- ⁇ Al is the standard deviation of the intensity I Al
- ⁇ AE is the intensity I AE
- I AE is the standard deviation of i .
- the covariance C Al, AE and the standard deviations ⁇ Al and ⁇ AE are given by the following equations (2) to (4), respectively.
- I Al, av is an arithmetic mean value of the intensity I Al, i given by the following equation (5)
- I AE, av is the intensity I AE, av given by the following equation (6) . It is an arithmetic mean value of i .
- the correlation coefficient ⁇ Al, AE represented by the equation (1) is an index representing the correlation between the aluminum distribution and the alkaline earth metal element distribution in the first catalyst layer 20A. That is, when the alkaline earth metal element is relatively uniformly distributed in the first catalyst layer 20A, the correlation coefficient ⁇ Al, AE becomes a large positive value of 1 or less. On the other hand, when the alkaline earth metal element is relatively non-uniformly distributed in the first catalyst layer 20A, the correlation coefficient ⁇ Al, AE becomes a small value close to zero.
- the uniformity of the distribution of the alkaline earth metal element in the second catalyst layer 20B can be similarly evaluated.
- the correlation coefficient ⁇ Al, AE thus obtained is an index representing the correlation between the aluminum distribution and the alkaline earth metal element distribution in the second catalyst layer 20B. That is, when the alkaline earth metal element is relatively uniformly distributed in the second catalyst layer 20B, this correlation coefficient ⁇ Al, AE becomes a large positive value of 1 or less. On the other hand, when the alkaline earth metal element is relatively unevenly distributed in the second catalyst layer 20B, the correlation coefficient ⁇ Al, AE becomes a small positive value close to zero.
- the correlation coefficient ⁇ Al, AE when used, the uniformity of the alkaline earth metal element distribution in each of the catalyst layers 20A and 20B can be evaluated.
- the correlation coefficients ⁇ Al, AE in the catalyst layers 20A and 20B are both large positive values of 1 or less. That is, in the exhaust gas-purifying catalyst 1, the alkaline earth metal element is distributed relatively uniformly in both the catalyst layers 20A and 20B.
- the correlation coefficient ⁇ Al, AE of the first catalyst layer 20A is preferably 0.61 or more, more preferably 0.70 or more, and further preferably 0.77 or more.
- the correlation coefficient ⁇ Al, AE of the second catalyst layer 20B is preferably 0.61 or more, more preferably 0.70 or more, and further preferably 0.77 or more.
- At least one of the catalyst layers 20A and 20B may further include an oxygen storage material.
- an oxygen storage material for example, cerium oxide, zirconium oxide, or a composite oxide thereof is used.
- rare earth oxides such as praseodymium oxide, transition metal oxides such as iron oxide and manganese oxide, or composite oxides thereof may be used as the oxygen storage material.
- a mixture of the above compounds may be used as the oxygen storage material.
- a composite oxide of cerium oxide and zirconium oxide is used as the oxygen storage material.
- At least one of the catalyst layers 20A and 20B may further contain a rare earth element.
- Rare earth element without reducing the HC purification performance of the exhaust gas purifying catalyst 1 has a function to improve the the NO x purification performance. Further, the rare earth element has a function of improving the heat resistance of the exhaust gas-purifying catalyst 1. Furthermore, the rare earth element has a function of suppressing a decrease in oxygen storage capacity of the oxygen storage material.
- this rare earth element for example, neodymium, lanthanum, praseodymium or yttrium is used. These rare earth elements are introduced, for example, as constituent components of the oxygen storage material.
- At least one of the catalyst layers 20A and 20B may further contain zeolite.
- Zeolite has a high specific surface area and is excellent in the ability to adsorb HC in exhaust gas. Therefore, the HC purification performance of the exhaust gas purification catalyst 1 can be further improved by containing zeolite.
- At least one of the catalyst layers 20A and 20B may further include a binder.
- the binder plays a role of improving the durability of the exhaust gas-purifying catalyst 1 by further strengthening the bond between a plurality of particles constituting at least one of the catalyst layers 20A and 20B.
- alumina sol, titania sol, or silica sol is used as the binder.
- the exhaust gas-purifying catalyst 1 may further include an additional layer in addition to the catalyst layers 20A and 20B. Thereby, various performances required for the exhaust gas-purifying catalyst 1 can be adjusted.
- the exhaust gas-purifying catalyst 1 is manufactured, for example, as follows.
- a slurry (hereinafter also referred to as a first slurry) containing at least one noble metal selected from the group consisting of palladium and platinum and alumina doped with an alkaline earth metal element is prepared.
- a noble metal selected from the group consisting of palladium and platinum and alumina doped with an alkaline earth metal element.
- a palladium salt such as palladium nitrate or a palladium complex
- platinum as a material of the first slurry
- examples of the material of the first slurry include a palladium salt such as palladium nitrate or a mixture of a palladium complex and a platinum complex such as dinitrodiamine platinum nitrate or a platinum salt. Is used.
- a slurry containing rhodium and alumina doped with an alkaline earth metal element (hereinafter also referred to as a second slurry) is prepared. After apply
- a rhodium salt such as rhodium nitrate or a rhodium complex
- examples of the material of the second slurry include rhodium salts such as rhodium nitrate or rhodium complexes and platinum such as dinitrodiamine platinum nitric acid.
- rhodium salts such as rhodium nitrate or rhodium complexes
- platinum such as dinitrodiamine platinum nitric acid.
- a complex or a mixture with a platinum salt is used. As described above, the exhaust gas-purifying catalyst 1 is obtained.
- the correlation coefficient ⁇ Al, AE described above can be further improved in at least one of the catalyst layers 20A and 20B.
- the present inventors speculate as follows. That is, the present inventors presume that citric acid stabilizes the molecular structure of alumina, and as a result, aggregation of alkaline earth metal is further suppressed.
- FIG. 2 is a cross-sectional view schematically showing an exhaust gas purifying catalyst according to a modification.
- the exhaust gas-purifying catalyst 1 shown in FIG. 2 is the same as the exhaust gas-purifying catalyst described with reference to FIG. 1 except that the stacking order of the first catalyst layer 20A and the second catalyst layer 20B is reversed. It has the same configuration.
- an exhaust gas purifying catalyst 1 having the structure shown in FIG. 1 is found to be particularly useful in purification of NO x. Further, the present inventors have found that the exhaust gas purifying catalyst 1 having the configuration shown in FIG. 2 is particularly useful for purifying HC. Therefore, by changing the stacking order of the catalyst layers 20A and 20B, it is possible to achieve the optimum exhaust gas purification performance corresponding to the application of the exhaust gas purification catalyst 1.
- Example 1 Production of catalyst C1> Alumina doped with 10% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA1”.
- CZ oxide A composite oxide of cerium oxide and zirconium oxide was prepared.
- the molar ratio of the cerium element to the zirconium element was 7/3.
- this composite oxide is referred to as “CZ oxide”.
- a slurry was prepared by mixing 50 g of Ba alumina BA1, 50 g of CZ oxide, a palladium nitrate aqueous solution containing 0.5 g of palladium, and 2 g of citric acid.
- this slurry is referred to as “slurry S1”.
- the slurry S1 was applied on the base material. Next, this was dried at 250 ° C. for 1 hour and then calcined at 500 ° C. for 1 hour. In this way, the first catalyst layer 20A using the slurry S1 as a raw material was formed on the base material.
- Alumina doped with 1.0% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA2”.
- ZC oxide A composite oxide of zirconium oxide and cerium oxide was prepared.
- this composite oxide the molar ratio of cerium element to zirconium element was 3/7.
- this composite oxide is referred to as “ZC oxide”.
- a slurry was prepared by mixing 50 g of Ba alumina BA2, 50 g of ZC oxide, an aqueous rhodium nitrate solution containing 0.5 g of rhodium, and 2 g of citric acid.
- this slurry is referred to as “slurry S2”.
- this slurry S2 was applied onto the first catalyst layer 20A using the slurry S1 as a raw material. Next, this was dried at 250 ° C. for 1 hour and then calcined at 500 ° C. for 1 hour. In this way, the second catalyst layer 20B using the slurry S2 as a raw material was formed on the first catalyst layer 20A using the slurry S1 as a raw material.
- catalyst C1 an exhaust gas purification catalyst
- Example 2 Production of catalyst C2 (comparative example)> A slurry was prepared by mixing 45 g of alumina, 50 g of CZ oxide, 8.5 g of barium sulfate, an aqueous palladium nitrate solution containing 0.5 g of palladium, and 2 g of citric acid.
- this slurry is referred to as “slurry S3”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S3 was used instead of the slurry S1.
- this catalyst is referred to as “catalyst C2”.
- the ratio of the barium mass to the sum of the alumina mass and the barium mass in the first catalyst layer 20A was 10% by mass.
- Example 3 Production of catalyst C3 (comparative example)> A slurry was prepared by mixing 49.5 g of alumina, 50 g of ZC oxide, 0.93 g of barium acetate, an aqueous rhodium nitrate solution containing 0.5 g of rhodium, and 2 g of citric acid.
- this slurry is referred to as “slurry S4”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S4 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C3”.
- Example 4 Production of catalyst C4 (comparative example)> A slurry was prepared by mixing 49.5 g of alumina, 50 g of ZC oxide, 0.85 g of barium sulfate, an aqueous rhodium nitrate solution containing 0.5 g of rhodium, and 2 g of citric acid.
- this slurry is referred to as “slurry S5”.
- a catalyst for exhaust gas purification was produced in the same manner as the catalyst C1, except that the slurry S3 was used instead of the slurry S1, and the slurry S5 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C4”.
- the ratio of the barium mass to the sum of the alumina mass and the barium mass in the first catalyst layer 20A was 10% by mass. Further, the ratio of the mass of barium to the sum of the mass of alumina and the mass of barium in the second catalyst layer 20B was 1.0% by mass.
- Table 1 below summarizes data relating to the catalysts C1 to C4.
- the column “amount of noble metal” describes the mass (g / L) of the noble metal per unit volume of the substrate.
- the column “introduction form” describes the introduction form of the alkaline earth metal element.
- the mass (g / L) of the alkaline earth metal element per unit volume of the substrate is described.
- mass ratio the mass ratio of the alkaline earth metal element to the noble metal is described.
- the correlation coefficients ⁇ Al, Ba of both the catalyst layers 20A and 20B were both large positive values close to 1. That is, in the catalyst C1, it was found that the alkaline earth metal element was relatively uniformly distributed in both the catalyst layers 20A and 20B.
- the correlation coefficient ⁇ Al, Ba of at least one of the catalyst layers 20A and 20B was a relatively small value. That is, in the catalysts C2 to C4, it was found that the alkaline earth metal element was distributed relatively unevenly in at least one of the catalyst layers 20A and 20B.
- E is a combined value of each exhaust gas emission amount in the JC08 mode
- E C is a measured value of each exhaust gas emission amount in the JC08C mode
- E H is a measured value of each exhaust gas emission amount in the JC08H mode. It is.
- the combined values of the exhaust gas emissions obtained in this way are summarized in Table 1 above.
- the catalyst C1 as compared to catalysts C2 to C4 had better HC, CO and NO x purification performance. That is, it became clear that excellent exhaust gas purification performance can be achieved by using alumina doped with an alkaline earth metal element for both the first catalyst layer 20A and the second catalyst layer 20B.
- Example 5 Production of catalyst C5> Exhaust gas in the same manner as in the catalyst C1, except that the slurry S2 is used instead of the slurry S1 as the material of the first catalyst layer 20A and the slurry S1 is used instead of the slurry S2 as the material of the second catalyst layer 20B. A purification catalyst was produced. Hereinafter, this catalyst is referred to as “catalyst C5”.
- Example 6 Production of catalyst C6> A slurry was prepared in the same manner as the slurry S1, except that a dinitrodiamine platinum nitrate aqueous solution containing 0.5 g of platinum was used instead of the palladium nitrate aqueous solution containing 0.5 g of palladium.
- this slurry is referred to as “slurry S6”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S6 was used instead of the slurry S1.
- this catalyst is referred to as “catalyst C6”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S7 was used instead of the slurry S1.
- this catalyst is referred to as “catalyst C7”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S8 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C8”.
- Example 9 Production of catalyst C9> Alumina doped with 20% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA3”.
- a slurry was prepared in the same manner as the slurry S1, except that 250 g of Ba alumina BA3 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S9”.
- Alumina doped with 0.1% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA4”.
- a slurry was prepared in the same manner as the slurry S2, except that 50 g of Ba alumina BA4 was used instead of 50 g of Ba alumina BA2.
- this slurry is referred to as “slurry S10”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S9 was used instead of the slurry S1, and the slurry S10 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C9”.
- Example 10 Production of catalyst C10> A slurry was prepared in the same manner as the slurry S1, except that 50 g of Ba alumina BA3 was used instead of 50 g of Ba alumina BA1. Hereinafter, this slurry is referred to as “slurry S11”.
- Alumina doped with 18% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA5”.
- catalyst C10 the catalyst for exhaust gas purification was manufactured in the same manner as the catalyst C1 except that the slurry S11 was used instead of the slurry S1 and the slurry S12 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C10”.
- Example 11 Production of catalyst C11> An exhaust gas purifying catalyst was produced in the same manner as the catalyst C10 except that the slurry S2 was used instead of the slurry S12. Hereinafter, this catalyst is referred to as “catalyst C11”.
- Example 12 Production of catalyst C12> A slurry was prepared in the same manner as the slurry S2, except that 50 g of Ba alumina BA1 was used instead of 50 g of Ba alumina BA2. Hereinafter, this slurry is referred to as “slurry S13”.
- Exhaust gas purification catalyst was produced in the same manner as catalyst C10 except that slurry S13 was used instead of slurry S12. Hereinafter, this catalyst is referred to as “catalyst C12”.
- Example 13 Production of catalyst C13> Alumina doped with 21% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA6”.
- a slurry was prepared in the same manner as the slurry S1, except that 250 g of Ba alumina BA6 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S14”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S14 was used instead of the slurry S1, and the slurry S15 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C13”.
- Example 14 Production of catalyst C14> An alumina doped with 10% by mass of strontium was prepared. Hereinafter, this is referred to as “Sr alumina SA1”.
- a slurry was prepared in the same manner as the slurry S1, except that 50 g of Sr alumina SA1 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S16”.
- a slurry was prepared in the same manner as the slurry S2, except that 50 g of Sr alumina SA2 was used instead of 50 g of Ba alumina BA2.
- this slurry is referred to as “slurry S17”.
- catalyst C14 the catalyst for exhaust gas purification was manufactured in the same manner as the catalyst C1 except that the slurry S16 was used instead of the slurry S1 and the slurry S17 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C14”.
- Example 15 Production of catalyst C15> Alumina doped with 10% by mass of calcium was prepared. Hereinafter, this is referred to as “Ca alumina CA1”.
- a slurry was prepared in the same manner as the slurry S1, except that 50 g of Ca alumina CA1 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S18”.
- Alumina doped with 1.0% by mass of calcium was prepared. Hereinafter, this is referred to as “Ca alumina CA2”.
- a slurry was prepared in the same manner as the slurry S2, except that 50 g of Ca alumina CA2 was used instead of 50 g of Ba alumina BA2.
- this slurry is referred to as “slurry S19”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S18 was used instead of the slurry S1, and the slurry S19 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C15”.
- Example 16 Production of catalyst C16> An alumina doped with 10% by mass of magnesium was prepared. Hereinafter, this is referred to as “Mg alumina MA1”.
- a slurry was prepared in the same manner as the slurry S1, except that 50 g of Mg alumina MA1 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S20”.
- Alumina doped with 1.0% by mass of magnesium was prepared. Hereinafter, this is referred to as “Mg alumina MA2”.
- a slurry was prepared in the same manner as the slurry S2, except that 50 g of Mg alumina MA2 was used instead of 50 g of Ba alumina BA2.
- this slurry is referred to as “slurry S21”.
- an exhaust gas purification catalyst was produced in the same manner as the catalyst C1, except that the slurry S20 was used instead of the slurry S1, and the slurry S21 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C16”.
- Example 17 Production of catalyst C17> A composite oxide of cerium oxide, zirconium oxide, yttrium oxide and praseodymium oxide was prepared. In this composite oxide, the molar ratio of cerium element, zirconium element, yttrium element, and praseodymium element was 6: 2: 1: 1. Hereinafter, this composite oxide is referred to as “CZYP oxide”.
- a slurry was prepared in the same manner as Slurry S1, except that 50 g of CZYP oxide was used instead of 50 g of CZ oxide.
- this slurry is referred to as “slurry S22”.
- a composite oxide of zirconium oxide, cerium oxide, lanthanum oxide and neodymium oxide was prepared.
- the molar ratio of zirconium element, cerium element, lanthanum element, and neodymium element was 7: 1: 1: 1.
- this composite oxide is referred to as “ZCLN oxide”.
- a slurry was prepared in the same manner as the slurry S2, except that 50 g of ZCLN oxide was used instead of 50 g of ZC oxide.
- this slurry is referred to as “slurry S23”.
- the catalyst for exhaust gas purification was manufactured in the same manner as the catalyst C1 except that the slurry S22 was used instead of the slurry S1 and the slurry S23 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C17”.
- Example 18 Production of catalyst C18 (comparative example)> Alumina doped with 22% by mass of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA8”.
- a slurry was prepared in the same manner as the slurry S1, except that 50 g of Ba alumina BA8 was used instead of 50 g of Ba alumina BA1.
- this slurry is referred to as “slurry S24”.
- slurry S25 a slurry was prepared in the same manner as the slurry S2, except that 50 g of Ba alumina BA8 was used instead of 50 g of Ba alumina BA2.
- this slurry is referred to as “slurry S25”.
- Example 19 Production of catalyst C19 (comparative example)> Alumina doped with 23% by weight of barium was prepared. Hereinafter, this is referred to as “Ba alumina BA9”.
- Example 20 Production of catalyst C20> A slurry was prepared in the same manner as the slurry S1, except that the addition of citric acid was omitted. Hereinafter, this slurry is referred to as “slurry S27”.
- a catalyst for exhaust gas purification was produced in the same manner as the catalyst C1, except that the slurry S27 was used instead of the slurry S1, and the slurry S28 was used instead of the slurry S2.
- this catalyst is referred to as “catalyst C20”.
- Figure 3 is a graph showing an example of the relationship between the ratio R and NO x emissions as described above. As shown in Tables 2 to 6 and FIG. 3, by setting the ratio R to less than 1, excellent exhaust gas purification performance could be achieved. Moreover, it turned out that the especially outstanding exhaust gas purification performance can be achieved by making ratio R into 0.001 or more and less than one. In addition, a comparison between the catalyst C1 and the catalyst C17 revealed that an excellent exhaust gas purification performance can be achieved by further introducing a rare earth element other than cerium.
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Abstract
Description
第2触媒層20Bは、ロジウムと、アルカリ土類金属元素がドープされたアルミナとを含んでいる。
第2触媒層20Bが含んでいる全貴金属の合計質量に対する第2触媒層20Bが含んでいる全アルカリ土類金属元素の合計質量の比(以下、第2質量比ともいう)は、第1触媒層20Aが含んでいる全貴金属の合計質量に対する第1触媒層20Aが含んでいる全アルカリ土類金属元素の合計質量の比(以下、第1質量比ともいう)と比較してより小さい。このような構成を採用すると、優れた排ガス浄化性能を達成することができる。
以上のようにして、排ガス浄化用触媒1を得る。
10質量%のバリウムをドープしたアルミナを準備した。以下、これを「BaアルミナBA1」と呼ぶ。
45gのアルミナと、50gのCZ酸化物と、8.5gの硫酸バリウムと、0.5gのパラジウムを含んだ硝酸パラジウム水溶液と、2gのクエン酸とを混合し、スラリーを調製した。以下、このスラリーを「スラリーS3」と呼ぶ。
49.5gのアルミナと、50gのZC酸化物と、0.93gの酢酸バリウムと、0.5gのロジウムを含んだ硝酸ロジウム水溶液と、2gのクエン酸とを混合し、スラリーを調製した。以下、このスラリーを「スラリーS4」と呼ぶ。
49.5gのアルミナと、50gのZC酸化物と、0.85gの硫酸バリウムと、0.5gのロジウムを含んだ硝酸ロジウム水溶液と、2gのクエン酸とを混合し、スラリーを調製した。以下、このスラリーを「スラリーS5」と呼ぶ。
触媒C1について、上述した相関係数ρAl,AE(AE=Ba)を、以下のようにして求めた。なお、相関係数ρAl,Baは、第1触媒層20A及び第2触媒層20Bの各々について求めた。
触媒C1乃至C4の各々について、排ガス浄化性能の評価を行った。
第1触媒層20Aの材料としてスラリーS1の代わりにスラリーS2を使用すると共に、第2触媒層20Bの材料としてスラリーS2の代わりにスラリーS1を使用したこと以外は、触媒C1と同様にして、排ガス浄化用触媒を製造した。以下、この触媒を「触媒C5」と呼ぶ。
0.5gのパラジウムを含んだ硝酸パラジウム水溶液の代わりに、0.5gの白金を含んだジニトロジアミン白金硝酸水溶液を使用したこと以外は、スラリーS1と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS6」と呼ぶ。
0.5gのパラジウムを含んだ硝酸パラジウム水溶液の代わりに、0.25gのパラジウムを含んだ硝酸パラジウム水溶液と0.25gの白金を含んだジニトロジアミン白金硝酸水溶液との混合溶液を使用したこと以外は、スラリーS1と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS7」と呼ぶ。
0.5gのロジウムを含んだ硝酸ロジウム水溶液の代わりに、0.25gのロジウムを含んだ硝酸ロジウム水溶液と0.25gの白金を含んだジニトロジアミン白金硝酸水溶液との混合溶液を使用したこと以外は、スラリーS2と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS8」と呼ぶ。
20質量%のバリウムをドープしたアルミナを準備した。以下、これを「BaアルミナBA3」と呼ぶ。
50gのBaアルミナBA1の代わりに50gのBaアルミナBA3を使用したこと以外は、スラリーS1と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS11」と呼ぶ。
スラリーS12の代わりにスラリーS2を使用したこと以外は、触媒C10と同様にして、排ガス浄化用触媒を製造した。以下、この触媒を「触媒C11」と呼ぶ。
50gのBaアルミナBA2の代わりに50gのBaアルミナBA1を使用したこと以外は、スラリーS2と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS13」と呼ぶ。
21質量%のバリウムをドープしたアルミナを準備した。以下、これを「BaアルミナBA6」と呼ぶ。
10質量%のストロンチウムをドープしたアルミナを準備した。以下、これを「SrアルミナSA1」と呼ぶ。
10質量%のカルシウムをドープしたアルミナを準備した。以下、これを「CaアルミナCA1」と呼ぶ。
10質量%のマグネシウムをドープしたアルミナを準備した。以下、これを「MgアルミナMA1」と呼ぶ。
セリウム酸化物とジルコニウム酸化物とイットリウム酸化物とプラセオジム酸化物との複合酸化物を準備した。この複合酸化物では、セリウム元素とジルコニウム元素とイットリウム元素とプラセオジム元素とのモル比は、6:2:1:1とした。以下、この複合酸化物を「CZYP酸化物」と呼ぶ。
22質量%のバリウムをドープしたアルミナを準備した。以下、これを「BaアルミナBA8」と呼ぶ。
23質量%のバリウムをドープしたアルミナを準備した。以下、これを「BaアルミナBA9」と呼ぶ。
クエン酸の添加を省略したこと以外は、スラリーS1と同様にして、スラリーを調製した。以下、このスラリーを「スラリーS27」と呼ぶ。
触媒C5乃至C20の各々について、先に触媒C1乃至C4について述べたのと同様の方法により、触媒層におけるアルカリ土類金属元素の分散性の評価を行った。その結果を、上記表5及び表6に示す。
触媒C5乃至C20の各々について、先に触媒C1乃至C4について述べたのと同様の方法により、排ガス浄化性能の評価を行った。その結果を、触媒C1に関する結果と併せて、上記表2乃至表4及び表6並びに図3に示す。
表2乃至表6並びに図3に示すように、比率Rを1未満とすることにより、優れた排ガス浄化性能を達成することができた。また、比率Rを0.001以上且つ1未満とすることにより、特に優れた排ガス浄化性能を達成できることが分かった。加えて、触媒C1と触媒C17との比較により、セリウム以外の希土類元素を更に導入することにより、際立って優れた排ガス浄化性能を達成できることが明らかとなった。
Claims (10)
- 基材と、
前記基材と向き合い、パラジウム及び白金からなる群より選ばれる少なくとも1つの貴金属と、アルカリ土類金属元素がドープされたアルミナとを含んだ第1触媒層であって、前記第1触媒層が含んでいる全貴金属の合計質量に対する前記第1触媒層が含んでいるパラジウム及び白金の合計質量の比は第1値であり、前記第1触媒層は、ロジウムを含んでいないか、又は、前記第1触媒層が含んでいる全貴金属の合計質量に対する前記第1触媒層が含んでいるロジウムの質量の比が第2値となるようにロジウムを更に含み、前記第1触媒層が含んでいる全貴金属の合計質量に対する前記第1触媒層が含んでいる全アルカリ土類金属元素の合計質量の比は第3値である第1触媒層と、
前記第1触媒層を間に挟んで前記基材と向き合っているか又は前記基材と前記第1触媒層との間に介在している第2触媒層であって、前記第2触媒層は、ロジウムと、アルカリ土類金属元素がドープされたアルミナとを含み、前記第2触媒層が含んでいる全貴金属の合計質量に対する前記第2触媒層が含んでいるロジウムの質量の比は前記第2値よりも大きく、前記第2触媒層は、パラジウム及び白金を含んでいないか、又は、前記第2触媒層が含んでいる全貴金属の合計質量に対する前記貴金属が含んでいるパラジウム及び白金の合計質量の比が前記第1値よりも小さいようにパラジウム及び白金の少なくとも一方を更に含み、前記第2触媒層が含んでいる全貴金属の合計質量に対する前記第2触媒層が含んでいる全アルカリ土類金属元素の合計質量の比は前記第3値よりも小さい第2触媒層と
を具備した排ガス浄化用触媒。 - 前記第1及び第2触媒層の双方は、下記式(1)により表される相関係数ρAl,AEが0.61以上である請求項1に記載の排ガス浄化用触媒。
iは1乃至175の自然数であり、
IAl,iは、前記第1触媒層又は前記第2触媒層を厚み方向に175等分して得られる面と前記第1触媒層又は前記第2触媒層の主面に垂直な直線との175個の交点のうちi番目の交点において、電子線マイクロアナライザを用いて測定したアルミニウムの特性X線強度であり、
IAl,avは、下記式(5)により与えられる前記IAl,iの相加平均値であり、
IAE,avは、下記式(6)により与えられる前記IAE,iの相加平均値である。
- 前記第2触媒層は、前記第1触媒層を間に挟んで前記基材と向き合っている請求項1又は2に記載の排ガス浄化用触媒。
- 前記第2触媒層は、前記基材と前記第1触媒層との間に介在している請求項1又は2に記載の排ガス浄化用触媒。
- 前記第2触媒層は白金を更に含んでいる請求項1乃至4の何れか1項に記載の排ガス浄化用触媒。
- 前記第2触媒層が含んでいる全貴金属の合計質量に対する前記第2触媒層が含んでいる全アルカリ土類金属元素の合計質量の比は第4値であり、前記第4値の前記第3値に対する比率は0.001乃至0.9の範囲内にある請求項1乃至5の何れか1項に記載の排ガス浄化用触媒。
- 前記第1及び第2触媒層の各々において、前記アルカリ土類金属元素のドープ量は、前記アルカリ土類金属元素がドープされたアルミナの質量を基準として0.1質量%乃至20質量%の範囲内にある請求項1乃至6の何れか1項に記載の排ガス浄化用触媒。
- 前記第1触媒層は、貴金属としてパラジウム及び白金の少なくとも一方のみを含み、前記第2触媒層は、貴金属としてロジウムのみ又はロジウム及び白金のみを含んだ請求項1乃至7の何れか1項に記載の排ガス浄化用触媒。
- 前記第1触媒層が含んでいる前記アルカリ土類金属元素及び前記第2触媒層が含んでいる前記アルカリ土類金属元素の少なくとも一方はバリウムである請求項1乃至8の何れか1項に記載の排ガス浄化用触媒。
- 前記第1触媒層は、パラジウム及び白金からなる群より選ばれる少なくとも1つの貴金属と、アルカリ土類金属元素がドープされたアルミナと、クエン酸とを含んだ第1スラリーを用いて形成され、前記第2触媒層は、ロジウムと、アルカリ土類金属元素がドープされたアルミナと、クエン酸とを含んだ第2スラリーを用いて形成される請求項1乃至9の何れか1項に記載の排ガス浄化用触媒。
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WO (1) | WO2010137657A1 (ja) |
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US20140147358A1 (en) * | 2012-11-12 | 2014-05-29 | Basf Se | Oxidation Catalyst And Method For Its Preparation |
JP2014200715A (ja) * | 2013-04-02 | 2014-10-27 | 株式会社キャタラー | 排ガス浄化用触媒 |
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1993017968A1 (en) * | 1992-03-12 | 1993-09-16 | Vista Chemical Company | Preparation of stabilized alumina having enhanced resistance to loss of surface area at high temperatures |
JPH11207183A (ja) | 1997-11-20 | 1999-08-03 | Daihatsu Motor Co Ltd | 排気ガス浄化用触媒 |
JP2001506177A (ja) * | 1996-02-21 | 2001-05-15 | エイエスイーシー・マニュファクチュアリング | 排気転化触媒のための高度に分散した実質的に均一な混合した金属―酸化物複合担体 |
JP2008290065A (ja) * | 2007-04-27 | 2008-12-04 | Mazda Motor Corp | 排気ガス浄化用触媒およびその製造方法 |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE69435061T2 (de) * | 1993-06-25 | 2008-12-18 | Basf Catalysts Llc | Katalysatorzusammensetzung |
US5948723A (en) * | 1996-09-04 | 1999-09-07 | Engelhard Corporation | Layered catalyst composite |
DE69728341T2 (de) * | 1996-10-07 | 2004-12-30 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Verbundoxid, Verbundoxidträger und Katalysator |
US6348430B1 (en) * | 1997-06-20 | 2002-02-19 | Degussa Ag | Exhaust gas treatment catalyst for internal combustion engines with two catalytically active layers on a carrier structure |
KR100326747B1 (ko) * | 1998-03-09 | 2002-03-13 | 하나와 요시카즈 | 산소 과잉 배기 가스의 정화 장치 |
US20020048542A1 (en) * | 1999-04-02 | 2002-04-25 | Michel Deeba | Catalytic trap and methods of making and using the same |
US6294140B1 (en) * | 1999-04-23 | 2001-09-25 | Degussa Ag | Layered noble metal-containing exhaust gas catalyst and its preparation |
US6764665B2 (en) * | 2001-10-26 | 2004-07-20 | Engelhard Corporation | Layered catalyst composite |
KR100781670B1 (ko) * | 2006-08-16 | 2007-12-03 | 희성촉매 주식회사 | 극소량의 로듐 또는 로듐을 포함하지 않는 내연기관배기가스 정화용 촉매 |
US7550124B2 (en) * | 2006-08-21 | 2009-06-23 | Basf Catalysts Llc | Layered catalyst composite |
US7517510B2 (en) * | 2006-08-21 | 2009-04-14 | Basf Catalysts Llc | Layered catalyst composite |
US20080044330A1 (en) * | 2006-08-21 | 2008-02-21 | Shau-Lin Franklin Chen | Layered catalyst composite |
US7754171B2 (en) * | 2007-02-02 | 2010-07-13 | Basf Corporation | Multilayered catalyst compositions |
US8007750B2 (en) * | 2007-07-19 | 2011-08-30 | Basf Corporation | Multilayered catalyst compositions |
DE102007046158B4 (de) * | 2007-09-27 | 2014-02-13 | Umicore Ag & Co. Kg | Verwendung eines katalytisch aktiven Partikelfilters zur Entfernung von Partikeln aus dem Abgas von mit überwiegend stöchiometrischem Luft/Kraftstoff-Gemisch betriebenen Verbrennungsmotoren |
JP5323093B2 (ja) * | 2008-12-19 | 2013-10-23 | 株式会社キャタラー | 排ガス浄化用触媒 |
-
2010
- 2010-05-27 JP JP2011516056A patent/JP5337875B2/ja active Active
- 2010-05-27 EP EP10780611.9A patent/EP2436441B1/en active Active
- 2010-05-27 WO PCT/JP2010/059016 patent/WO2010137657A1/ja active Application Filing
- 2010-05-27 CN CN201080022779.7A patent/CN102448606B/zh active Active
-
2011
- 2011-11-22 US US13/301,859 patent/US8580706B2/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1993017968A1 (en) * | 1992-03-12 | 1993-09-16 | Vista Chemical Company | Preparation of stabilized alumina having enhanced resistance to loss of surface area at high temperatures |
JP2001506177A (ja) * | 1996-02-21 | 2001-05-15 | エイエスイーシー・マニュファクチュアリング | 排気転化触媒のための高度に分散した実質的に均一な混合した金属―酸化物複合担体 |
JPH11207183A (ja) | 1997-11-20 | 1999-08-03 | Daihatsu Motor Co Ltd | 排気ガス浄化用触媒 |
JP2008290065A (ja) * | 2007-04-27 | 2008-12-04 | Mazda Motor Corp | 排気ガス浄化用触媒およびその製造方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2436441A4 |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2013065421A1 (ja) * | 2011-10-31 | 2015-04-02 | エヌ・イーケムキャット株式会社 | 排気ガス浄化用触媒 |
EP2774671A4 (en) * | 2011-10-31 | 2015-07-08 | N E Chemcat Corp | EMISSION CONTROL CATALYST |
US20140147358A1 (en) * | 2012-11-12 | 2014-05-29 | Basf Se | Oxidation Catalyst And Method For Its Preparation |
JP2014200715A (ja) * | 2013-04-02 | 2014-10-27 | 株式会社キャタラー | 排ガス浄化用触媒 |
JP2018508337A (ja) * | 2015-01-19 | 2018-03-29 | 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Umicore AG & Co.KG | 経時劣化安定性が改善された二重層三元触媒 |
JP2017124347A (ja) * | 2016-01-12 | 2017-07-20 | マツダ株式会社 | パティキュレートフィルタ |
WO2017146175A1 (ja) * | 2016-02-25 | 2017-08-31 | 株式会社キャタラー | 排ガス浄化触媒及びその製造方法 |
JPWO2017146175A1 (ja) * | 2016-02-25 | 2018-11-29 | 株式会社キャタラー | 排ガス浄化触媒及びその製造方法 |
JP2021531956A (ja) * | 2018-07-27 | 2021-11-25 | ジョンソン、マッセイ、パブリック、リミテッド、カンパニーJohnson Matthey Public Limited Company | 改良されたtwc触媒を含有する高ドーパント担体 |
US11794170B2 (en) | 2018-07-27 | 2023-10-24 | Johnson Matthey Public Limited Company | TWC catalysts containing high dopant support |
WO2020067000A1 (ja) * | 2018-09-28 | 2020-04-02 | ユミコア日本触媒株式会社 | 排ガス浄化触媒、排ガスの浄化方法、及び排ガス浄化触媒の製造方法 |
US11446639B2 (en) | 2018-09-28 | 2022-09-20 | Umicore Shokubai Japan Co., Ltd. | Exhaust gas purification catalyst, exhaust gas purification method, and production method for exhaust gas purification catalyst |
Also Published As
Publication number | Publication date |
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JPWO2010137657A1 (ja) | 2012-11-15 |
EP2436441B1 (en) | 2017-06-14 |
CN102448606B (zh) | 2014-03-26 |
EP2436441A1 (en) | 2012-04-04 |
CN102448606A (zh) | 2012-05-09 |
US8580706B2 (en) | 2013-11-12 |
EP2436441A4 (en) | 2013-07-31 |
US20120065058A1 (en) | 2012-03-15 |
JP5337875B2 (ja) | 2013-11-06 |
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