US4013760A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of isotropic pyrolytic carbon particles
Assignee: Hobeg Hochtemperaturreaktor Brennelement GmbH
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Filing: 1974-07-11
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Granted: 1977-03-22
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Expires: 1994-07-11
Abstract
Abstract Graphite or carbon molded articles of high isotropy and high heat conductivity, especially useful for high temperature reactor fuel elements are prepared by pressing a mixture of a binder and a powdery carbon filler which consists partially or wholly of pyrolytically produced isotropic carbon with subsequent heat treatment of the pressed article. There is used as the filler an isotropic pyrolytic carbon made by depositing a hydrocarbon on a carbon granulate and then grinding to a particle size of less than 100 μm.
Inventors
- 👤 Hans Huschka
- 👤 Franz-Josef Herrmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:00
CPC Classifications
G; G21; G21C; G21C21/00; G21C21/02; C; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/528; C04B35/532; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
64 words
A process of producing isotropic pyrolytic carbon particles of high heat conductivity comprising pyrolyzing a hydrocarbon gas on isotropic carbon granulates to form a deposit of isotropic pyrolytic carbon on the isotropic carbon granulates having a particle size above 100μm and then grinding to form an isotropic carbon powder having a particle size below 100μm and an average particle size larger than 5 μm.
Claim 2
Dependent Claim
64 words
A process of producing isotropic pyrolytic carbon particles of high heat conductivity comprising pyrolyzing a hydrocarbon gas on isotropic carbon granulates to form a deposit of isotropic pyrolytic carbon on the isotropic carbon granulates having a particle size above 100μm and then grinding to form an isotropic carbon powder having a particle size below 100μm and an average particle size larger than 5 μm.
Claim 3
Dependent Claim
22 words
A process according to claim 1, wherein the ground powder particles have an average particle size of between 15 and 60 μm.
Claim 4
Dependent Claim
15 words
A process according to claim 2, wherein the average particle size is about 30 μm.
Claim 5
Dependent Claim
15 words
A process according to claim 1, wherein the hydrocarbon gas is methane, propylene or acetylene.
Claim 6
Dependent Claim
53 words
A process according to claim 1, wherein the depositing is carried out in a fludized bed and there are included the steps after grinding of separating coarse particles having a particle size above 100 μm and returning the coarse particles to the fluidized bed as granulates for deposition of isotropic, pyrolytic carbon thereon.
Claim 7
Dependent Claim
26 words
A process according to claim 5 wherein the isotropic carbon powder having a particle size below 100 μm is annealed at a temperature above 2000° C.
Claim 8
Dependent Claim
18 words
A process according to claim 6, wherein the annealing is at a temperature of up to 2500° C.
Claim 9
Dependent Claim
25 words
A process according to claim 1 wherein the isotropic carbon powder having a particle size below 100μm is annealed at a temperature above 2000° C.
Claim 10
Dependent Claim
18 words
A process according to claim 8 wherein the annealing is at a temperature of up to 2500° C.
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) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |