Patent US4404177A successfully refreshed from Google Patents.
US4404177A
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Method for producing graphite crystals
Assignee: Mobil Oil AS
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Filing: 1981-11-12
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Granted: 1983-09-13
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Expires: 2001-11-12
Abstract
Abstract A process for continuously or semi-continuously producing and collecting highly oriented graphite crystals by diffusing carbon atoms through a heated Group VIII metal artifact such that they precipitate as graphite on a surface of the artifact. Diffusion of carbon atoms through the artifact is driven by maintaining a temperature differential across the artifact.
Inventors
- 👤 Francis J. Derbyshire
- 👤 Darrell D. Whitehurst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:04
CPC Classifications
C; C30; C30B; C30B1/00; C01; C01B; C01B32/00; C01B32/20; C01B32/205; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C23; C23C; C23C16/00; C23C16/22; C23C16/26; C30B29/00; C30B29/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
123 words
An improved process for continuously or semi-continuously producing highly oriented graphite crystals, said process comprising: (A) introducing a source of carbon atoms to a first surface of an artifact comprising a Group VIII metal or mixture of Group VIII metals, said first surface being maintained at a temperature of from about 700° C. to 1800° C., (B) maintaining a temperature differential of at least 100° C. across said artifact such that carbon atoms diffuse through said artifact to a generally opposite solid second surface of said artifact, said second surface being maintained at a temperature of from about 500° C. to 1250° C.; and (C) collecting graphite crystals which form on said second surface from carbon atoms which have diffused through said artifact.
Claim 2
Dependent Claim
123 words
An improved process for continuously or semi-continuously producing highly oriented graphite crystals, said process comprising: (A) introducing a source of carbon atoms to a first surface of an artifact comprising a Group VIII metal or mixture of Group VIII metals, said first surface being maintained at a temperature of from about 700° C. to 1800° C., (B) maintaining a temperature differential of at least 100° C. across said artifact such that carbon atoms diffuse through said artifact to a generally opposite solid second surface of said artifact, said second surface being maintained at a temperature of from about 500° C. to 1250° C.; and (C) collecting graphite crystals which form on said second surface from carbon atoms which have diffused through said artifact.
Claim 3
Dependent Claim
33 words
The process of claim 1 wherein said first surface has a temperature between about 900° C. and 1250° C.; and said second surface has a temperature between about 600° C. and 1000° C.
Claim 4
Dependent Claim
13 words
The process of claim 2 wherein said artifact is in the solid state.
Claim 5
Dependent Claim
17 words
The process of claim 2 wherein the first surface of said artifact is in the molten state.
Claim 6
Dependent Claim
21 words
The process of claim 2 wherein said Group VIII metal is selected from the group consisting of cobalt, nickel and iron.
Claim 7
Dependent Claim
12 words
The process of claim 5 wherein said Group VIII metal is cobalt.
Claim 8
Dependent Claim
12 words
The process of claim 5 wherein said Group VIII metal is nickel.
Claim 9
Dependent Claim
20 words
The process of claim 2 wherein the graphite is collected by mechanical scraping of said second surface of the artifact.
Claim 10
Dependent Claim
12 words
The process of claim 1 wherein the carbon source is elemental carbon.
Claim 11
Dependent Claim
12 words
The process of claim 1 wherein the carbon source is a hydrocarbon.
Claim 12
Dependent Claim
15 words
The process of claim 1 wherein the carbon source is a non-hydrocarbon carbon containing compound.
Claim 13
Dependent Claim
25 words
The process of claim 2 wherein said temperature differential is attained by continuously heating one surface of the artifact and continuously cooling an opposite surface.
Claim 14
Dependent Claim
16 words
The process of claim 12 wherein a temperature differential of at least 200° C. is maintained.
References Cited (Backward Citations)
US3274097A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-12 | 1987-03-14 | 1987-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-12 | 1991-03-14 | 1991-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-12 | 1995-03-14 | 1995-09-13 | $7700.00 | Window Closed / Lapsed |