US4944991A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formation of alumina impregnated carbon fiber mats
Assignee: Electric Power Research Institute
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Filing: 1988-07-08
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Granted: 1990-07-31
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Expires: 2008-07-08
Abstract
Abstract A process for the formation of alumina containing carbon fiber mats is provided. The process comprises dispersing an alumina precursor solution in the mat, converting the precursor to an insoluble hydroxide precipitate and hydrolizing the precipitate to form alumina nodules dispersed throughout the mat. Also provided is an alumina containing carbon fiber mat comprising carbon fibers and nodules of alumina, which are substantially uniformly dispersed throughout the mat, and a sodium sulfur cell having a sulfur compartment containing such a mat.
Inventors
- 👤 Bradley R. Karas
- 👤 Robert W. Powers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:02
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/64; H01M4/66; H01M4/663; H01M10/00; H01M10/36; H01M10/39; H01M10/3909; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257; Y10T428/30; Y10T442/00; Y10T442/20; Y10T442/2033
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
48 words
A process for the formation of an alumina containing carbon fiber mat comprising: a. dispersing an alumina precursor solution in said mat; b. converting said dispersed alumina precursor to an insoluble hydroxide precipitate; and c. pyrolizing said aluminum hydroxide precipitate to form alumina nodules dispersed throughout said mat.
Claim 2
Dependent Claim
48 words
A process for the formation of an alumina containing carbon fiber mat comprising: a. dispersing an alumina precursor solution in said mat; b. converting said dispersed alumina precursor to an insoluble hydroxide precipitate; and c. pyrolizing said aluminum hydroxide precipitate to form alumina nodules dispersed throughout said mat.
Claim 3
Dependent Claim
15 words
The process according to claim 1 wherein said alumina nodules are adhered to said mat.
Claim 4
Dependent Claim
14 words
The process according to claim 1 wherein said alumina precursor is an aluminum salt.
Claim 5
Dependent Claim
26 words
The process according to claim 3 wherein said aluminum salt is selected from the group consisting of aluminum sulfate, aluminum nitrate, aluminum acetate and aluminum formate.
Claim 6
Dependent Claim
13 words
The process according to claim 3 wherein said aluminum salt is aluminum sulfate.
Claim 7
Dependent Claim
14 words
The process according to claim 1 wherein said alumina precursor is an aluminum alkoxide.
Claim 8
Dependent Claim
21 words
The process according to claim 6 wherein said aluminum alkoxide is diluted with an organic solvent before dispersion in said mat.
Claim 9
Dependent Claim
13 words
The process according to claim 6 wherein said aluminum alkoxide is aluminum sec-butoxide.
Claim 10
Dependent Claim
13 words
The process according to claim 6 wherein said aluminum alkoxide is aluminum iso-propoxide.
Claim 11
Dependent Claim
23 words
The process according to claim 3 wherein said aluminum salt is converted to said insoluble hydroxide by the addition of a cationic hydroxide.
Claim 12
Dependent Claim
13 words
The process according to claim 10 wherein said cationic hydroxide is ammonium hydroxide.
Claim 13
Dependent Claim
18 words
The process according to claim 6 wherein said aluminum alkoxide is converted to said insoluble hydroxide by heating.
Claim 14
Dependent Claim
15 words
The process according to claim 12 wherein said heating is performed by contact with steam.
Claim 15
Dependent Claim
19 words
The process according to claim 1 additionally comprising the step of drying said mat after precipitating said aluminum hydroxide.
Claim 16
Dependent Claim
20 words
The process according to claim 1 wherein step (a) is performed by submerging said mat in said alumina precursor solution.
Claim 17
Dependent Claim
24 words
The process according to claim 14 additionally comprising the step of applying a vacuum to said mat after submersion in said alumina precursor solution.
Claim 18
Dependent Claim
15 words
An alumina containing carbon fiber mat formed by the process of claims 1 or 12.
Claim 19
Dependent Claim
41 words
An alumina containing carbon fiber mat comprising carbon fibers and nodules of alumina, said nodules being formed by dispersing an aluminum hydroxide throughout said mat, precipitating said aluminum hydroxide and pyrolizing said aluminum hydroxide to form alumina nodules within said mat.
Claim 20
Dependent Claim
41 words
An alumina containing carbon fiber mat comprising carbon fibers and nodules of alumina, said nodules being formed by dispersing an aluminum hydroxide throughout said mat, precipitating said aluminum hydroxide and pyrolizing said aluminum hydroxide to form alumina nodules within said mat.
Claim 21
Dependent Claim
19 words
A carbon mat comprising carbon fibers and nodules of alumina, said nodules being substantially uniformly dispersed throughout said mat.
Claim 22
Dependent Claim
19 words
A carbon mat comprising carbon fibers and nodules of alumina, said nodules being substantially uniformly dispersed throughout said mat.
Claim 23
Dependent Claim
19 words
The carbon mat according to claim 19 wherein said nodules are between about 10 and 300 microns in diameter.
Claim 24
Dependent Claim
15 words
The carbon mat according to claim 20 wherein said nodules adhere to said carbon fibers.
Claim 25
Dependent Claim
26 words
A sodium sulfur cell having a sulfur compartment containing a mat, said mat comprising carbon fibers and nodules of alumina dispersed substantially uniformly among said fibers.
Claim 26
Dependent Claim
26 words
A sodium sulfur cell having a sulfur compartment containing a mat, said mat comprising carbon fibers and nodules of alumina dispersed substantially uniformly among said fibers.
Claim 27
Dependent Claim
12 words
The cell of claim 22 wherein said nodules adhere to said fibers.
Claim 28
Dependent Claim
20 words
The cell of claim 23 wherein said nodules fall in the range of about 10 to 300 microns in diameter.
Claim 29
Dependent Claim
21 words
The cell of claim 24 having an electrical resistivity substantially equivalent to a sulfur cell not containing a carbon fiber mat.
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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) | 1993-07-30 | 1994-01-29 | 1994-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-30 | 1998-01-29 | 1998-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-30 | 2002-01-29 | 2002-07-31 | $7700.00 | Window Closed / Lapsed |