US4565683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of carbon filaments
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1984-07-06
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Granted: 1986-01-21
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Expires: 2004-07-06
Abstract
Abstract Disclosed is a method for producing carbon filaments by dissociating a carbon-containing gas at a temperature to about 800° C. in the presence of iron monoxide. The iron monoxide can be produced by treating a sample of substantially pure iron with steam at a temperature from about 540° C.
Inventors
- 👤 David J. C. Yates
- 👤 Rees T. Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:03
CPC Classifications
C; C01; C01G; C01G49/00; C01G49/02; C01G49/04; B; B82; B82Y; B82Y30/00; D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/127; D01F9/1273; D01F9/1275; D01F9/1278; C01P; C01P2002/00; C01P2002/80; C01P2004/00; C01P2004/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
156 words
A method for producing carbon filaments, which method comprises: (a) heating a metallic iron composition, comprised of at least about 95 wt. % iron, to a temperature of at least about 540° C., which iron composition is in a form selected from tube, sheet, rod, foil, and gauze; (b) contacting the heated iron composition with steam for an amount of time which will convert all, or a portion of, the iron composition to FeO, but no greater than the time at which FeO begins to convert to Fe 3 O 4 ; and (c) contacting the resulting iron monoxide with one or more carbon-containing gases at a temperature from the dissociation temperature of the gas to about 800° C., wherein the iron composition is substantially free of: (aa) elements which form protective oxides at the temperature employed in step (a) above; and (bb) metal components which are volatile at the temperature employed in step (a) above.
Claim 2
Independent Claim
156 words
A method for producing carbon filaments, which method comprises: (a) heating a metallic iron composition, comprised of at least about 95 wt. % iron, to a temperature of at least about 540° C., which iron composition is in a form selected from tube, sheet, rod, foil, and gauze; (b) contacting the heated iron composition with steam for an amount of time which will convert all, or a portion of, the iron composition to FeO, but no greater than the time at which FeO begins to convert to Fe 3 O 4 ; and (c) contacting the resulting iron monoxide with one or more carbon-containing gases at a temperature from the dissociation temperature of the gas to about 800° C., wherein the iron composition is substantially free of: (aa) elements which form protective oxides at the temperature employed in step (a) above; and (bb) metal components which are volatile at the temperature employed in step (a) above.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein the carbon-containing gas is selected from the group consisting of carbon monoxide, acetylenes, olefins and paraffins.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein the carbon-containing gas is selected from the group consisting of the C 2 to C 4 paraffins.
Claim 5
Dependent Claim
21 words
The method of claim 1 wherein the temperature employed in step (a) is from about 700° C. to about 800° C.
References Cited (Backward Citations)
GB1469930A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-20 | 1989-07-22 | 1990-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-20 | 1993-07-22 | 1994-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-20 | 1997-07-22 | 1998-01-21 | $7700.00 | Window Closed / Lapsed |