EP0341832B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Treatment of diesel exhaust gas
Assignee: Johnson Matthey Inc
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Filing: 1989-04-12
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Granted: 1996-01-10
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Expires: 2009-04-12
Abstract
Abstract In a process wherein diesel exhaust gas is passed through a filter (3) to remove particulate therefrom before discharge and particulate deposited on the filter is combusted, the improvement which comprises combusting the particulate with a gas containing NO2 which may be catalytically generated in the exhaust system (1).
Inventors
- 👤 Barry John Cooper
- 👤 Hyun Jong Jung
- 👤 James Edmund Thoss
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 16:44
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/44; C09C1/48; C09C1/50; F; F01; F01N; F01N13/00; F01N13/009; F01N3/00; F01N3/02; F01N3/021; F01N3/023; F01N3/0231; F01N3/029; F01N3/08; F01N3/10; F01N3/24; F01N3/28; F01N3/2882; C01; C01P; C01P2004/00; C01P2004/80; C01P2004/82; C01P2004/84; F01N2250/00; F01N2250/02; F01N2330/00; F01N2330/06; F01N2330/12; F02; F02B; F02B3/00; F02B3/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
A process for removing, by combustion, particulate deposited on a filter (3) disposed in a diesel exhaust system, characterised in that exhaust gas containing NO is initially passed without filtering over a catalyst (1) to convert the NO in the exhaust gas to NO₂ prior to filtering to remove particulate and in that the exhaust gas containing NO₂ is then used to combust the particulate trapped on the filter (3), the amount of NO converted to NO₂ being sufficient to enable combustion of particulate trapped on filter (3) to proceed at a temperature less than 400°C.
Claim 2
Dependent Claim
17 words
A process according to Claim 1, characterised in that the gas containing NO₂ also includes water vapor.
Claim 3
Dependent Claim
16 words
A process according to Claim 1, characterised in that the catalyst comprises a platinum group metal.
Claim 4
Dependent Claim
25 words
A process according to any of Claims 1 to 3, characterised in that the catalyst comprises a platinum group metal on a monolithic honeycomb (1).
Claim 5
Dependent Claim
20 words
A process according to any preceding claim, characterised in that the filter (3) includes a catalyst which facilitates particulate combustion.
Claim 6
Dependent Claim
16 words
A process according to Claim 5, characterised in that the filter catalyst comprises a base metal.
Claim 7
Dependent Claim
21 words
A process according to Claim 6, characterised in that the filter catalyst comprises a combination of lanthanum, cesium and vanadium pentoxide.
Claim 8
Independent Claim
67 words
A system for processing diesel exhaust gas, using the process according to any preceding claim, comprising a honeycomb monolith (1) which includes a catalyst for oxidizing NO in the gas to NO₂; means for passing said exhaust gas through said zone so that NO gas is converted to NO₂; and means (3) for filtering particulate positioned downstream of said zone to receive NO₂-containing gas from said zone.
References Cited (Backward Citations)
No citation records indexed.
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