US6122909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalytic reduction of emissions from internal combustion engines
Assignee: Lynntech Power Systems Ltd
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Filing: 1998-09-29
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Granted: 2000-09-26
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Expires: 2018-09-29
Abstract
Abstract An apparatus for treating an exhaust gas stream from cold startup through continuous operating conditions of an internal combustion engine includes an oxidizing catalyst bed disposed in an exhaust pipe and a reducing catalyst bed disposed in the exhaust pipe downstream from the oxidizing catalyst bed. The oxidizing catalyst bed has one or more oxidizing catalysts and the reducing catalyst bed has one or more reducing catalysts. A method is provided for treating an exhaust gas stream both during cold start and during continuous operating conditions of an internal combustion engine by passing the stream through an oxidizing catalyst bed having one or more oxidizing catalysts at a light off temperature; a reducing catalyst bed having one or more reducing catalysts and providing hydrogen into the reducing catalyst bed to condition the reducing catalyst; and introducing hydrogen into the internal combustion engine during cold startup.
Inventors
- 👤 Oliver J. Murphy
- 👤 Craig C. Andrews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:34
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/2006; F01N3/2046; F01N13/00; F01N13/009; F01N3/206; F02; F02M; F02M25/00; F02M25/10; F02M25/12; F01N2610/00; F01N2610/04; F01N2610/08; F01N3/24; F01N3/30; F01N3/32; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y10; Y10S; Y10S123/00; Y10S123/12
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
154 words
An apparatus for treating exhaust from an internal combustion engine in communication with an exhaust pipe, comprising: an oxidizing catalyst bed disposed in the exhaust pipe; a reducing catalyst bed disposed in the exhaust pipe downstream from the oxidizing catalyst bed; a source of hydrogen having a first control valve providing fluid communication with the oxidizing catalyst bed, a second control valve providing fluid communication with the reducing catalyst bed, and a third control valve providing fluid communication with the internal combustion engine; a source of oxygen having a control valve providing fluid communication with the oxidizing catalyst bed; and a control system for conditioning the oxidizing catalyst bed prior to receiving significant amounts of exhaust having a component selected from hydrocarbons, carbon monoxide, and combinations thereof, conditioning the reducing catalyst bed prior to receiving significant amounts of exhaust having NO x , and providing hydrogen to the internal combustion engine during cold start.
Claim 2
Independent Claim
154 words
An apparatus for treating exhaust from an internal combustion engine in communication with an exhaust pipe, comprising: an oxidizing catalyst bed disposed in the exhaust pipe; a reducing catalyst bed disposed in the exhaust pipe downstream from the oxidizing catalyst bed; a source of hydrogen having a first control valve providing fluid communication with the oxidizing catalyst bed, a second control valve providing fluid communication with the reducing catalyst bed, and a third control valve providing fluid communication with the internal combustion engine; a source of oxygen having a control valve providing fluid communication with the oxidizing catalyst bed; and a control system for conditioning the oxidizing catalyst bed prior to receiving significant amounts of exhaust having a component selected from hydrocarbons, carbon monoxide, and combinations thereof, conditioning the reducing catalyst bed prior to receiving significant amounts of exhaust having NO x , and providing hydrogen to the internal combustion engine during cold start.
Claim 3
Dependent Claim
29 words
The system of claim 1, wherein the oxidizing catalyst bed is conditioned during a cold start ignition by opening the first hydrogen control valve and the oxygen control valve.
Claim 4
Dependent Claim
19 words
The system of claim 1, wherein the reducing catalyst bed is conditioned by opening the second hydrogen control valve.
Claim 5
Dependent Claim
18 words
The system of claim 2, wherein the oxidizing catalyst bed is conditioned until reaching a light off temperature.
Claim 6
Dependent Claim
22 words
The system of claim 1, wherein the reducing catalyst is conditioned selectively continuous or discontinuous throughout operation of the internal combustion engine.
Claim 7
Dependent Claim
20 words
The system of claim 1, wherein the oxidizing catalyst bed is selected from a two-way catalyst and a three-way catalyst.
Claim 8
Dependent Claim
22 words
The system of claim 1, further comprising hydrogen delivery ports in communication with one or more regions of the reducing catalyst bed.
Claim 9
Dependent Claim
17 words
The system of claim 1, wherein the reducing catalyst bed includes essentially no catalyst for oxidizing nitrogen.
Claim 10
Dependent Claim
14 words
The system of claim 1, wherein the source of hydrogen includes an on-board electrolyzer.
Claim 11
Dependent Claim
27 words
The system of claim 9, wherein the on-board electrolyzer has an anode for producing oxygen, and wherein the anode is in fluid communication with the oxygen source.
Claim 12
Dependent Claim
20 words
The system of claim 1, wherein the third control valve provides hydrogen to the internal combustion engine during cold start.
Claim 13
Independent Claim
85 words
A method for preventing and treating exhaust gas from an internal combustion engine, comprising: supplying hydrogen fuel to an internal combustion engine during cold start; passing the exhaust gas over one or more oxidizing catalysts and then over one or more reducing catalysts; oxidizing one or more oxidizable components in the exhaust gas over the one or more oxidizing catalysts; providing hydrogen gas to the one or more reducing catalysts; and reducing one or more reducible components in the exhaust gas over the reducing catalysts.
Claim 14
Independent Claim
85 words
A method for preventing and treating exhaust gas from an internal combustion engine, comprising: supplying hydrogen fuel to an internal combustion engine during cold start; passing the exhaust gas over one or more oxidizing catalysts and then over one or more reducing catalysts; oxidizing one or more oxidizable components in the exhaust gas over the one or more oxidizing catalysts; providing hydrogen gas to the one or more reducing catalysts; and reducing one or more reducible components in the exhaust gas over the reducing catalysts.
Claim 15
Dependent Claim
22 words
The method of claim 12, wherein the one or more reducing catalysts are selected from Pt, Ru, Pt-alloys, Ru-alloys and combinations thereof.
Claim 16
Dependent Claim
36 words
The method of claim 12, wherein the one or more reducible components comprises a nitrogen oxide, and wherein the nitrogen oxide is reduced to nitrogen gas and water vapor at the one or more reducing catalysts.
Claim 17
Dependent Claim
32 words
The method of claim 12, wherein the one or more oxidizable components are selected from hydrocarbons, carbon monoxide and combinations thereof and the one or more reducible components includes a nitrogen oxide.
Claim 18
Dependent Claim
24 words
The method of claim 12, wherein the internal combustion engine burns a fuel selected from gasoline, diesel, natural gas and methanol after cold startup.
Claim 19
Dependent Claim
43 words
The method of claim 16, further comprising: providing hydrogen and oxygen to the one or more oxidizing catalysts at a time selected from before the internal combustion engine is started and before the exhaust gas stream contacts the one or more oxidizing catalysts.
Claim 20
Dependent Claim
27 words
The method of claim 17, further comprising: heating the one or more oxidizing catalysts by exothermic catalytic combination of hydrogen and oxygen up to a light-off temperature.
Claim 21
Dependent Claim
24 words
The method of claim 17, wherein the hydrogen is substantially continuously provided to the one or more reducing catalysts after the engine warm-up period.
Claim 22
Dependent Claim
23 words
The method of claim 12, wherein the hydrogen is provided to the one or more reducing catalysts only after an engine warm-up period.
Claim 23
Dependent Claim
24 words
The method of claim 20, wherein the hydrogen is substantially continuously provided to the one or more reducing catalysts after the engine warm-up period.
Claim 24
Dependent Claim
35 words
The method of claim 12, wherein the hydrogen is provided to the one or more reducing catalysts before an engine warm-up period to condition the one or more reducing catalysts prior to introducing nitrogen oxides.
Claim 25
Dependent Claim
23 words
The method of claim 12, further comprising electrolytically producing the hydrogen at a rate proportional to the load on the internal combustion engine.
Claim 26
Dependent Claim
19 words
The method of claim 23, further comprising: storing a portion of the produced hydrogen in a hydrogen storage vessel.
Claim 27
Dependent Claim
23 words
the method of claim 24, wherein the hydrogen provided to the one or more oxidizing catalysts is supplied from the hydrogen storage vessel.
Claim 28
Dependent Claim
24 words
The method of claim 25, further comprising: stopping hydrogen to the one or more oxidizing catalysts after the oxidizing catalysts reach a light-off temperature.
Claim 29
Dependent Claim
23 words
The method of claim 23, further comprising: starting the electrolyzer and providing hydrogen to the reducing catalysts only after an engine warm-up period.
Claim 30
Dependent Claim
24 words
The method of claim 27, wherein the hydrogen is substantially continuously provided to the one or more reducing catalysts after the engine warm-up period.
Claim 31
Dependent Claim
23 words
The method of claim 27, wherein the hydrogen is discontinuously provided to the one or more reducing catalysts after the engine warm-up period.
Claim 32
Dependent Claim
27 words
The method of claim 12, further comprising: heating the one or more oxidizing catalysts by exothermic catalytic combination of hydrogen and oxygen up to a light-off temperature.
Claim 33
Dependent Claim
28 words
the method of claim 12, further comprising: providing hydrogen to the one or more reducing catalysts before the exhaust gas stream contacts the one or more reducing catalysts.
Claim 34
Dependent Claim
23 words
The method of claim 12, wherein the hydrogen is provided into the internal combustion engine for about one minute or more following startup.
Claim 35
Dependent Claim
24 words
The method of claim 12, wherein the hydrogen is provided into the internal combustion engine for between about 30 seconds and about one minute.
Claim 36
Dependent Claim
23 words
The method of claim 12, wherein the hydrogen is provided into the internal combustion engine for between about 10 and about 15 seconds.
Claim 37
Dependent Claim
26 words
The method of claim 12, wherein the one or more reducing catalysts are disposed on a support material selected from alumina, silica, zeolite, and titanium dioxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-09-26 | 2004-03-27 | 2004-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-09-26 | 2008-03-27 | 2008-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-09-26 | 2012-03-27 | 2012-09-26 | $7700.00 | Window Closed / Lapsed |