Patent EP0198948A2 successfully refreshed from Google Patents.
EP0198948A2
Expired / Lapsed
EP
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Catalytic combustor for combustion of lower hydrocarbon fuel
Assignee: Nippon Shokubai Co Ltd
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Filing: 1985-09-19
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Granted: —
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Expires: 2005-09-19
Abstract
Abstract A method for the combustion of a lower hydrocarbon fuel by the use of a catalyst system provided, relative to the flow of a flammable mixed gas comprising said lower hydrocarbon having 1 to 4 carbon atoms and molecular oxygen, on the inlet side thereof with a front-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of palladium and platinum and an active component formed of palladium, platinum, and nickel oxides and on the outlet side thereof with a rear-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of platinum and an active component formed of platinum and palladium, which method comprises feeding said flammable mixed gas to said catalyst system, allowing at least part of said lower hydrocarbon in said mixed gas to undergo catalytic combustion in said catalyst system, and enabling the temperature of resultant combustion gas to rise to a level enough to induce secondary combustion.
Inventors
- 👤 Makoto Horiuchi
- 👤 Tetsuji Ono
- 👤 Kazuo Tsuchitani
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 19:11
CPC Classifications
F; F23; F23C; F23C13/00
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
173 words
A method for the combustion of a lower hydrocarbon fuel by the use of a catalyst system provided, relative to the flow of a flammable mixed gas comprising said lower hydrocarbon having 1 to 4 carbon atoms and molecular oxygen, on the inlet side thereof with a front-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of palladium and platinum and an active component formed of palladium, platinum, and nickel oxides and on the outlet side thereof with a rear-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of platinum and an active component formed of platinum and palladium, which method comprises feeding said flammable mixed gas to said catalyst system, allowing at least part of said lower hydrocarbon in said mixed gas to undergo catalytic combustion in said catalyst system, and enabling the temperature of resultant combustion gas to rise to a level enough to induce secondary combustion.
Claim 2
Independent Claim
173 words
A method for the combustion of a lower hydrocarbon fuel by the use of a catalyst system provided, relative to the flow of a flammable mixed gas comprising said lower hydrocarbon having 1 to 4 carbon atoms and molecular oxygen, on the inlet side thereof with a front-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of palladium and platinum and an active component formed of palladium, platinum, and nickel oxides and on the outlet side thereof with a rear-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of platinum and an active component formed of platinum and palladium, which method comprises feeding said flammable mixed gas to said catalyst system, allowing at least part of said lower hydrocarbon in said mixed gas to undergo catalytic combustion in said catalyst system, and enabling the temperature of resultant combustion gas to rise to a level enough to induce secondary combustion.
Claim 3
Dependent Claim
39 words
A method according to Claim 1, wherein said active component is deposited as dispersed on refractory carrier monoliths coated with at least one refractory metal oxide selected from the group consisting of alumina, silica-alumina, magnesia, titania, zirconia and silica-magnesia.
Claim 4
Dependent Claim
102 words
A method according to Claim 2, wherein the amounts of said active components of said catalyst used for said front-stage catalyst bed are 0.5 to 15% by weight of palladium and 0.1 to 10% by weight of platinum and, where nickel is also contained, 0.1 to 20% by weight of nickel as NiO respectively based on a completed catalyst and the amounts of said active components of said catalyst used for said rear-stage catalyst bed are 0.1 to 15% by weight of platinum and, where palladium is also contained, 0.1 to 15% by weight of palladium respectively based on a completed catalyst..
Claim 5
Dependent Claim
39 words
A method according to Claim 3, wherein the amount of platinum in sai active components of said catalyst for said front-stage catalyst bed in the range of 0.01 to 1 part by weight per part by weight of palladium.
Claim 6
Dependent Claim
37 words
A method according to Claim 2, Wherein the amount of said refractory metal oxide used for_coating said carrier monoliths is in the range of 5 to 50% by weight based on the amount of a completed catalyst.
Claim 7
Dependent Claim
40 words
A method according to Claim 2, wherein the coating layer formed of said refractory metal oxide is stabilized with the oxide of at least one metal selected from the group consisting of silicon, alkaline earth metals, and rare earth metals.
Claim 8
Dependent Claim
38 words
A method according to Claim 6, wherein the amount of said stabilizing metal oxide to be added is in the range of 2 to 20% by weight based on the amount of said refractory metal oxide for coating.
Claim 9
Dependent Claim
26 words
A method according to Claim 2, wherein said refractory metal oxide is at least one member selected from the group consisting of alumina, titania, and zirconia.
Claim 10
Dependent Claim
13 words
A method according to Claim 2, wherein said refractory metal oxide is alumina.
Claim 11
Dependent Claim
19 words
A method according to Claim 6, wherein said stabilizing metal oxide is the oxide of a rare earth metal.
Claim 12
Dependent Claim
25 words
A method according to Claim 10, wherein said rare earth metal is selected from the group consisting of lanthanum, yttrium, cerium, samarium, neodymium, and praseodymium.
Claim 13
Dependent Claim
19 words
A method according to Claim 6, wherein said stabilizing metal oxide is the oxide of an alkaline earth metal.
Claim 14
Dependent Claim
23 words
A method according to Claim 12, wherein said alkaline earth metal is selected from the group consisting of magnesium, calcium, strontium, and barium.
Claim 15
Dependent Claim
26 words
A method according to Claim 1, wherein said platinum as an active component possesses an average particle diameter in the range of 0.01 to 5 microns.
Claim 16
Dependent Claim
31 words
A method according to Claim 6, wherein said stabilizing metal oxide is the oxide of at least one metal selected from the group consisting of lanthanum, cerium, neodymium, praseodymium, and silicon.
Claim 17
Dependent Claim
19 words
A method according to Claim 1, wherein said temperature enough to induce secondary combustion is not less than 750°C.
Claim 18
Dependent Claim
32 words
A method according to Claim 16, wherein said lower hydrocarbon is added as secondary fuel to said combustion gas whose temperature has been elevated to said temperature enough to induce secondary combustion.
Claim 19
Dependent Claim
12 words
A method according to Claim 1, wherein said lower hydrocarbon is methane.
Claim 20
Dependent Claim
66 words
A method according to Claim 1, wherein an intermediate-stage catalyst bed packed with a catalyst containing at least one active component selected from the group consisting of an active component formed of palladium and nickel oxides , an active component formed of platinum, and an active component formed of palladium, platinum, and nickel oxides is interposd between said front-stage catalyst bed and said rear-stage catalyst bed.
Claim 21
Dependent Claim
38 words
A method according to Claim 19, wherein said active component is deposited as dispersed on refractory carrier monoliths coated with at least one refractory metal oxide selected from the group consisting of alumina, silica-alumina, magnesia, titania,zirconia and silica-magnesia.
Claim 22
Dependent Claim
47 words
A method according to Claim 20, wherein the amounts of said active components are 0.5 to 15% by weight of palladium, 0.1 to 10% by weight of platinum, and 0.1 to 20% by weight of nickel as NiO respectively based on the amount of a completed catalyst.
Claim 23
Dependent Claim
35 words
A method according to Claim 20, wherein the amount of said refractory metal oxide used for coating said carrier monoliths is in the range of 5 to 50% by weight based on a completed catalyst.
Claim 24
Dependent Claim
41 words
A method ccording to Claim 20, wherein the coaling layer formed of a said refractory metal oxide is stabilized with the oxide of at least one metal selected from the group consisting of silicon, alkaline earth metals, and rare earth metals.
Claim 25
Dependent Claim
39 words
24 . A method according to Claim 23, wherein-the amount of said stabilizing metal oxide to be added is in the range of 2 to 20% by weight based on the amount of said refractory metal oxide for coating.
Claim 26
Dependent Claim
26 words
A method according to Claim 20, wherein said refractory metal oxide is at least one member selected from the group consisting of alumina, titania, and zirconia.
Claim 27
Dependent Claim
19 words
A method according to Claim 19, wherein said temperature enough to induce secondary combustion is not less than 750°C.
Claim 28
Dependent Claim
32 words
A method according to Claim 26, wherein said lower hydrocarbon is added as secondary fuel to said combustion gas whose temperature has been elevated to said temperature enough to induce secondary combustion.
Claim 29
Dependent Claim
158 words
A catalyst system for the combustion of a lower hydrocarbon. which is provided,relative to the flow of a flammable mixed gas consisting of said lower hydrocarbon having 1 to 4 carbon atoms and molecular oxygen, on the inlet side thereof with a front-stage catalyst bed packed with a catalyst containing one active component selected from the group consisting of an active component formed of palladium and platinum and an active component formed of and nickel oxides and on the outlet rear-stage catalyst bed packed with a active component selected from the vactive component formed of platinum formed of platinum and palladium. system according to Claim 28, wherein catalyst bed packed with a catalyst active component selected from the group consisting of an active component formed of palladium and nickel oxides, an active component formed of platinum, an active component formed of palladium, platinum, and nickel oxides is interposd between said front-stage catalyst bed and said rear-stage catalyst bed.
References Cited (Backward Citations)
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