US4157316A
Expired / Lapsed
US
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Polyfunctional catalysts
Assignee: BASF Catalysts LLC
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Filing: 1977-09-16
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Granted: 1979-06-05
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Expires: 1997-09-16
Abstract
Abstract This invention provides polyfunctional catalysts comprising a composite of platinum and one or more of rhodium, ruthenium and iridium, a substantially larger quantity of one or more base metal oxides in which the metal is selected from the group consisting of metals having an atomic number from 25 to 28 and rhenium, and an alumina support, which composite is made and then deposited on a suitable carrier. In a preferred embodiment, the catalysts contain 1-20 weight percent of said base metal oxide, typically nickel oxide; 0.05-0.5 weight percent platinum; and 0.002-0.3 weight percent rhodium, and an alumina support deposited on a monolith or other carrier. The improved catalysts are especially applicable for purifying exhaust gases from combustion processes, and in particular those from internal combustion engines. These polyfunctional catalysts have in a single formulation, the ability to accomplish four objectives - to oxidize carbon monoxide and unburned hydrocarbons while reducing nitrogen oxides, thereby converting those contaminants found in the exhaust of internal combustion engines into carbon dioxide, water and elemental nitrogen, but without producing significant amounts of hydrogen sulfide, sulfur trioxide or sulfuric acid. Such chemical conversions take place over the catalyst when the ratio of air to fuel supplied to the catalyst is controlled to nearly stoichiometric conditions, thereby maintaining the exhaust feed gases within a narrow compositional range, sometimes called a "window," in which the catalyst can substantially convert the contaminants.
Inventors
- 👤 Charles E. Thompson
- 👤 John J. Mooney
- 👤 Carl D. Keith
- 👤 William A. Mannion
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:23
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/56; B01J23/70; B01J23/89; B01J37/00; B01J37/02; B01J37/0238; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
252 words
A catalyst suitable for simultaneously oxidizing gaseous hydrocarbons and carbon monoxide and reducing nitrogen oxides, consisting essentially of (a) a support consisting essentially of alumina; (b) platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus at least one of rhodium, ruthenium, iridium and mixtures thereof, and alloys of said platinum group metals; (c) a base metal oxide component, the base metal being selected from the group consisting of metals having an atomic number from 25 to 28 and rhenium, and mixtures thereof, said base metal oxide being present in a weight ratio of said platinum group metal component of at least 2 to 1 and; (d) a carrier on which said support, composited with both said platinum group metal component and said base metal oxide component are deposited; (e) said catalyst being prepared by combining said platinum group metal component, said base metal oxide component, and said support by impregnating said support in particulate form with the following compounds in aqueous solution: a compound of said base metal, a compound of platinum; and one or more of a compound of rhodium, a compound of ruthenium, or a compound of iridium; the resulting impregnated support being deposited on said carrier by contacting said carrier with an aqueous dispersion of particles of said impregnated support, and heating said impregnated support at a temperature sufficiently high to provide on said carrier a composite of said platinum group metal component, said base metal oxide component and said support.
Claim 2
Dependent Claim
252 words
A catalyst suitable for simultaneously oxidizing gaseous hydrocarbons and carbon monoxide and reducing nitrogen oxides, consisting essentially of (a) a support consisting essentially of alumina; (b) platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus at least one of rhodium, ruthenium, iridium and mixtures thereof, and alloys of said platinum group metals; (c) a base metal oxide component, the base metal being selected from the group consisting of metals having an atomic number from 25 to 28 and rhenium, and mixtures thereof, said base metal oxide being present in a weight ratio of said platinum group metal component of at least 2 to 1 and; (d) a carrier on which said support, composited with both said platinum group metal component and said base metal oxide component are deposited; (e) said catalyst being prepared by combining said platinum group metal component, said base metal oxide component, and said support by impregnating said support in particulate form with the following compounds in aqueous solution: a compound of said base metal, a compound of platinum; and one or more of a compound of rhodium, a compound of ruthenium, or a compound of iridium; the resulting impregnated support being deposited on said carrier by contacting said carrier with an aqueous dispersion of particles of said impregnated support, and heating said impregnated support at a temperature sufficiently high to provide on said carrier a composite of said platinum group metal component, said base metal oxide component and said support.
Claim 3
Dependent Claim
19 words
The catalyst of claim 1 wherein said platinum group metal consists essentially of platinum and rhodium, and optionally, palladium.
Claim 4
Dependent Claim
10 words
The catalyst of claim 1 wherein the carrier is monolithic.
Claim 5
Dependent Claim
15 words
The catalyst of claim 1 wherein the base metal oxide consists essentially of nickel oxide.
Claim 6
Dependent Claim
19 words
The catalyst of claim 4 wherein the platinum group metal consists essentially of platinum and rhodium, and optionally palladium.
Claim 7
Dependent Claim
48 words
The catalyst of claim 5 wherein platinum is 0.05 to 0.5 weight percent and rhodium is 0.002 to 0.3 weight percent of the catalyst, the amount of platinum is at least equal to the amount of rhodium, and the nickel oxide is 1 to 20% of the catalyst.
Claim 8
Dependent Claim
10 words
The catalyst of claim 6 wherein the carrier is monolithic.
Claim 9
Dependent Claim
15 words
The catalyst of claim 7 wherein the support consists essentially of alumina stabilized by ceria.
Claim 10
Dependent Claim
333 words
A catalyst suitable for simultaneously oxidizing gaseous hydroncarbons and carbon monoxide and reducing nitrogen oxides, consisting essentially of (a) a support consisting essentially of alumina: (b) a platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus at least one of rhodium, ruthenium, iridium, and mixtures and alloys thereof, said platinum group metal component being deposited on said support by mixing said support in particulate form with compounds of said platinum group metals in solution in an aqueous medium, said compounds of said platinum group metals essentially including a compound of platinum and at least one of a compound of rhodium, a compound of ruthenium and a compound of iridium, said support and aqueous medium being present in amounts such that essentially all of said aqueous medium is absorbed by said support, and fixing said platinum group metal on said support; (c) a base metal oxide component, the base metal being selected from the group consisting of metals having an atomic number from 25 to 28 and rhenium, and mixtures thereof, said base metal oxide component being present in a weight ratio to said platinum group metals of at least 2 to 1 and being deposited on said support by mixing said support in particulate form with an aqueous solution containing a compound of said base metal, said support and aqueous solution being present in amounts such that essentially all of said aqueous solution is absorbed by said support, and fixing said base metal as an oxide on said support; (d) a carrier on which said support, composited with both said platinum group metal component, and said base metal oxide component are deposited as defined hereinbelow; (e) said catalyst being made by contacting said carrier with an aqueous dispersion of particles of said impregnated support and heating said impregnated support at a temperature sufficiently high to provide on said carrier a composite of said platinum group metal component, said base metal oxide component and said support.
Claim 11
Dependent Claim
333 words
A catalyst suitable for simultaneously oxidizing gaseous hydroncarbons and carbon monoxide and reducing nitrogen oxides, consisting essentially of (a) a support consisting essentially of alumina: (b) a platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus at least one of rhodium, ruthenium, iridium, and mixtures and alloys thereof, said platinum group metal component being deposited on said support by mixing said support in particulate form with compounds of said platinum group metals in solution in an aqueous medium, said compounds of said platinum group metals essentially including a compound of platinum and at least one of a compound of rhodium, a compound of ruthenium and a compound of iridium, said support and aqueous medium being present in amounts such that essentially all of said aqueous medium is absorbed by said support, and fixing said platinum group metal on said support; (c) a base metal oxide component, the base metal being selected from the group consisting of metals having an atomic number from 25 to 28 and rhenium, and mixtures thereof, said base metal oxide component being present in a weight ratio to said platinum group metals of at least 2 to 1 and being deposited on said support by mixing said support in particulate form with an aqueous solution containing a compound of said base metal, said support and aqueous solution being present in amounts such that essentially all of said aqueous solution is absorbed by said support, and fixing said base metal as an oxide on said support; (d) a carrier on which said support, composited with both said platinum group metal component, and said base metal oxide component are deposited as defined hereinbelow; (e) said catalyst being made by contacting said carrier with an aqueous dispersion of particles of said impregnated support and heating said impregnated support at a temperature sufficiently high to provide on said carrier a composite of said platinum group metal component, said base metal oxide component and said support.
Claim 12
Dependent Claim
27 words
A catalyst of claim 9 in which said fixings of said platinum group metals and said base metal are conducted in the absence of unabsorbed aqueous medium.
Claim 13
Dependent Claim
306 words
A catalyst for simultaneously oxidizing gaseous hydrocarbons and carbon monoxide and reducing nitrogen oxides consisting essentially of (a) a support consisting essentially of alumina; (b) a platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus rhodium, mixtures and alloys thereof, said platinum group metal component being about 0.05 to 0.8 weight percent of the catalyst and the amount of platinum being at least equal to the amount of rhodium, said platinum group metal component being deposited on said support by mixing said support in particulate form with a compound of platinum and a compound of rhodium in solution in an aqueous medium, said support and aqueous medium being present in amounts such that essentially all of said aqueous medium is absorbed by said support and fixing said platinum group metal on said support in the absence of unabsorbed aqueous medium; (c) nickel oxide being 1 to 20 weight percent of the catalyst and deposited on said support by mixing said support in particulate form with an aqueous solution containing a compound of nickel, said support and aqueous solution being present in amounts such that essentially all of said aqueous solution is absorbed by said support, and fixing the nickel of said nickel compound as nickel oxide on said support in the absence of unabsorbed aqueous medium; and (d) a monolithic carrier on which a composite of said support, composited with both said platinum group metal component and said nickel oxide are deposited as defined hereinbelow; (e) said catalyst being prepared by comminuting said support containing said platinum group metal component and said nickel oxide in an aqueous medium to provide an aqueous slurry, and contacting the resulting slurry with said carrier and heating said slurry at a temperature sufficient by high to provide on said carrier said composite.
Claim 14
Dependent Claim
306 words
A catalyst for simultaneously oxidizing gaseous hydrocarbons and carbon monoxide and reducing nitrogen oxides consisting essentially of (a) a support consisting essentially of alumina; (b) a platinum group metal component, the platinum group metal being selected from the group consisting of platinum plus rhodium, mixtures and alloys thereof, said platinum group metal component being about 0.05 to 0.8 weight percent of the catalyst and the amount of platinum being at least equal to the amount of rhodium, said platinum group metal component being deposited on said support by mixing said support in particulate form with a compound of platinum and a compound of rhodium in solution in an aqueous medium, said support and aqueous medium being present in amounts such that essentially all of said aqueous medium is absorbed by said support and fixing said platinum group metal on said support in the absence of unabsorbed aqueous medium; (c) nickel oxide being 1 to 20 weight percent of the catalyst and deposited on said support by mixing said support in particulate form with an aqueous solution containing a compound of nickel, said support and aqueous solution being present in amounts such that essentially all of said aqueous solution is absorbed by said support, and fixing the nickel of said nickel compound as nickel oxide on said support in the absence of unabsorbed aqueous medium; and (d) a monolithic carrier on which a composite of said support, composited with both said platinum group metal component and said nickel oxide are deposited as defined hereinbelow; (e) said catalyst being prepared by comminuting said support containing said platinum group metal component and said nickel oxide in an aqueous medium to provide an aqueous slurry, and contacting the resulting slurry with said carrier and heating said slurry at a temperature sufficient by high to provide on said carrier said composite.
Claim 15
Dependent Claim
15 words
The catalyst of claim 11 wherein said support consists essentially of alumina stabilized by ceria.
Claim 16
Dependent Claim
14 words
The catalyst of claim 1 wherein said support consists essentially of alumina and ceria.
Claim 17
Dependent Claim
26 words
The catalyst of claim 1 wherein said impregnated support is heated on said carrier to drive off free water and then is calcined on said carrier.
Claim 18
Dependent Claim
54 words
The catalyst of claim 1 wherein the step of impregnating said support with said compounds in aqueous solution is followed by a step of drying and calcining the resulting impregnated support prior to the steps of forming said aqueous dispersion of particles of said impregnated support and contacting said carrier with said aqueous dispersion.
Claim 19
Dependent Claim
72 words
The catalyst of claim 15 wherein the base metal oxide consists essentially of nickel oxide, the platinum group metal consists essentially of platinum and rhodium, and optionally palladium, platinum is 0.05 to 0.5 weight percent and rhodium is 0.002 to 0.3 weight percent of the catalyst, the amount of platinum is at least equal to the amount of rhodium, and the nickel oxide is 1 to 20 weight percent of the catalyst.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-04 | 1982-12-04 | 1983-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-04 | 1986-12-04 | 1987-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-04 | 1990-12-04 | 1991-06-05 | $7700.00 | Window Closed / Lapsed |