EP0396085A2
Expired / Lapsed
EP
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Catalyst for purification of exhaust gases
Assignee: Toyota Motor Corp
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Filing: 1990-04-30
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Granted: —
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Expires: 2010-04-30
Abstract
Abstract A catalyst used for purifying exhaust gases resulting from the combustion of a lean fuel-air mixture mixture comprises a porous support material having a framework formed by MO2, where M is silicon or a metal, AlO2 and PO2, and at least one base metal and at least one metal of the platinum group which are carried on the support material. The catalyst exhibits a high level of NOx conversion for a long time even at a high temperature owing to the high heat resistance and durability of the support material, and the cooperative action of the two kinds of metals, i.e. the promotion of the catalytic action of the base metal (e.g. copper) by the metal of the platinum group (e.g. palladium) serving as a cocatalyst.
Inventors
- 👤 Yoshihide Watanabe
- 👤 Mareo Kimura
- 👤 Shinichi Matsumoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 05:48
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J27/00; B01J27/14; B01J27/185; B01J27/1856; B01J27/186; B01J29/00; B01J29/82; B01J29/84; B01J29/85; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
67 words
A catalyst for purifying exhaust gases comprising: a porous support material having a framework comprising MO₂, where M is an element selected from silicon and a metal selected from the group consisting of Mg, Mn, Zn, Co, Fe, and Ti, AlO₂ and PO₂; and catalytically active elements comprising at least one base metal and at least one metal of the platinum group, carried on said support material.
Claim 2
Dependent Claim
67 words
A catalyst for purifying exhaust gases comprising: a porous support material having a framework comprising MO₂, where M is an element selected from silicon and a metal selected from the group consisting of Mg, Mn, Zn, Co, Fe, and Ti, AlO₂ and PO₂; and catalytically active elements comprising at least one base metal and at least one metal of the platinum group, carried on said support material.
Claim 3
Dependent Claim
15 words
The catalyst as set forth in claim 1, wherein said support material comprises crystalline silicoaluminophosphate.
Claim 4
Dependent Claim
15 words
The catalyst as set forth in claim 1, wherein said support material comprises crystalline metalloaluminophosphate.
Claim 5
Dependent Claim
23 words
The catalyst as set forth in claim 1, wherein said support material has uniformly sized pores with a nominal diameter exceeding 3 Å.
Claim 6
Dependent Claim
18 words
The catalyst as set forth in claim 4, wherein said nominal diameter is Between 5 and 10 Å.
Claim 7
Dependent Claim
53 words
The catalyst as set forth in claim 1, wherein said support material is of the chemical composition represented mainly by the empirical formula: (Si x Al y P z )O₂ where x + y + z = 1, 0.01 ≦ x < 0.8, and 0.01 ≦ z, when it is an anhydrous compound.
Claim 8
Dependent Claim
22 words
The catalyst as set forth in claim 1, wherein said at least one base metal is selected from the 3d transition metals.
Claim 9
Dependent Claim
32 words
The catalyst as set forth in claim 1, wherein said at least one metal of the platinum group is selected from the group consisting of Pd, Pt, Rh, Ir, Ru and Re.
Claim 10
Dependent Claim
23 words
The catalyst as set forth in claim 1, wherein said base metal is copper, while said metal of the platinum group is palladium.
Claim 11
Dependent Claim
28 words
The catalyst as set forth in claim 9, wherein said support material carries said palladium in an amount ranging from 10 to 50% by weight of said copper.
Claim 12
Dependent Claim
36 words
The catalyst as set forth in claim 1, wherein said base metal and said metal of the platinum group are so located on said support material as to be capable of performing a cooperative catalytic action.
Claim 13
Dependent Claim
31 words
The catalyst as set forth in claim 11, wherein said base metal and said metal of the platinum group form a mixture in which they exist alternately in a random pattern.
Claim 14
Dependent Claim
39 words
The catalyst as set forth in claim 11, wherein said base metal and said metal of the platinum group form a two-layer structure in which particles of one of said metals cover the surfaces of particles of the other.
References Cited (Backward Citations)
No citation records indexed.
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