US3872213A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing harmful components from exhaust gases
Assignee: Kobe Steel Ltd
•
Filing: 1972-08-30
•
Granted: 1975-03-18
•
Expires: 1992-08-30
Abstract
Abstract The present invention is concerned with a new method for removing harmful components such as nitrogen oxides, hydrocarbons and carbon monoxide from exhaust gases, especially automobile exhaust gases, by passing the exhaust gases entrained with oxygen through a catalyst bed which selectively oxidizes hydrogen, then passing the treated gases through a catalyst bed which selectively reduces the nitrogen oxides in the gases, and finally passing the gases into a catalyst bed which oxidizes the carbon monoxide and hydrocarbons in the gases.
Inventors
- 👤 Shigeru Haseba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:47
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9459; B01D53/9404; B01D53/9409; B01D53/9413; B01D53/944; B01D2255/00; B01D2255/10; B01D2255/102; B01D2255/1021; B01D2255/1023; B01D2255/20; B01D2255/207; B01D2255/20753; B01D2255/20761; B01D2255/20784; Y; Y02; Y02A; Y02A50/00; Y02A50/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
181 words
A METHOD FOR THE CATALYTIC CONVERSION OF HARMFUL COMPONENTS IN EXHAUST GASES CONTAINING NITROGEN OXIDES, CARBON MONOXIDES, HYDROGEN AND HYDROCARBONS, WHICH COMPRISES: CHARGING OXYGEN OR AN OXYGEN CONTAINING GAS INTO SAID EXHAUST GASES IN AMOUNTS SUFFICIENT TO COMPLETELY OXIDIZE SAID HYDROGEN COMPONENT BYT LESS THAN HALF THE TOTAL QUANTITY OF OXYGEN NEEDED TO OXIDIZE BOTH THE HYDROGEN AND CARBON MONOXIDE COMPONENTS IN SAID EXHAUST GASES; INTRODUCING SAID OXYGEN CONTAINING EXHAUST GASES INTO AN OXIDIZING CATALYST BED AT A TEMPERATURE OF 50* - 300=C SUFFICIENT TO OXIDIZE SAID HYDROGEN IN THE EXHAUST GASES AND TO REMOVE ALL OF SAID OXYGEN FROM SAID EXHAUST GASES; INTRODUCING THE EXHAST GASES ISSUING FROM SAID OXIDIXING CATALYST BED INTO A NITROGEN OXIDE REDUCING CATALYST BED AT A TEMPERATURE ABOVE 300*C TO REDUCE THE NITROGEN OXIDES PRESENT IN THE EXHAUST GASES; ADMIXING THE EXHAUST GASES ISSUING FROM SAID REDUCING CATALYST BED WITH ADDITIONAL OXYGEN OR OXYGEN CONTAINING GAS; AND INTRUDICING SAID ADMIXTURE INTO A SECOND OXIDIZING CATALYST BED AT A TEMPERATURE OF 100* - 700*C TO OXIDIZE ANY REMAINING CARBON MONOXIDE AND HYDROCARBONS IN SAID EXHAUST GASES.
Claim 2
Independent Claim
181 words
A METHOD FOR THE CATALYTIC CONVERSION OF HARMFUL COMPONENTS IN EXHAUST GASES CONTAINING NITROGEN OXIDES, CARBON MONOXIDES, HYDROGEN AND HYDROCARBONS, WHICH COMPRISES: CHARGING OXYGEN OR AN OXYGEN CONTAINING GAS INTO SAID EXHAUST GASES IN AMOUNTS SUFFICIENT TO COMPLETELY OXIDIZE SAID HYDROGEN COMPONENT BYT LESS THAN HALF THE TOTAL QUANTITY OF OXYGEN NEEDED TO OXIDIZE BOTH THE HYDROGEN AND CARBON MONOXIDE COMPONENTS IN SAID EXHAUST GASES; INTRODUCING SAID OXYGEN CONTAINING EXHAUST GASES INTO AN OXIDIZING CATALYST BED AT A TEMPERATURE OF 50* - 300=C SUFFICIENT TO OXIDIZE SAID HYDROGEN IN THE EXHAUST GASES AND TO REMOVE ALL OF SAID OXYGEN FROM SAID EXHAUST GASES; INTRODUCING THE EXHAST GASES ISSUING FROM SAID OXIDIXING CATALYST BED INTO A NITROGEN OXIDE REDUCING CATALYST BED AT A TEMPERATURE ABOVE 300*C TO REDUCE THE NITROGEN OXIDES PRESENT IN THE EXHAUST GASES; ADMIXING THE EXHAUST GASES ISSUING FROM SAID REDUCING CATALYST BED WITH ADDITIONAL OXYGEN OR OXYGEN CONTAINING GAS; AND INTRUDICING SAID ADMIXTURE INTO A SECOND OXIDIZING CATALYST BED AT A TEMPERATURE OF 100* - 700*C TO OXIDIZE ANY REMAINING CARBON MONOXIDE AND HYDROCARBONS IN SAID EXHAUST GASES.
Claim 3
Dependent Claim
30 words
The method of claim 1, wherein the heat generated in said oxidizing catalyst bed by the reaction of hydrogen and oxygen is transferred into said nitrogen oxide reducing catalyst bed.
Claim 4
Dependent Claim
35 words
The method of claim 1, wherein the catalytic material for oxidizing hydrogen in said oxidizing catalyst bed is substantially the same as that used for reducing nitrogen oxides in said nitrogen oxide reducing catalyst bed.
Claim 5
Dependent Claim
29 words
The method of claim 1, wherein a supported catalyst selected from the group consisting of copper chromite, palladium, and nickel is employed in said nitrogen oxide reducing catalyst bed.
Claim 6
Dependent Claim
17 words
The method of claim 1, wherein a supported platinum catalyst is employed in said oxidizing catalyst bed.
Claim 7
Dependent Claim
31 words
The method of claim 1, wherein at least one supported catalyst selected from the group consisting of copper chromite, platinum, palladium, and nickel is employed in said second oxidizing catalyst bed.
Claim 8
Dependent Claim
19 words
The method of claim 1 wherein from 40- 70% CO conversion to CO2 occurs in the oxidizing bed steps.
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) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |