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Patent US4225463A successfully refreshed from Google Patents.
US4225463A
Expired / Lapsed
US
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Porous carbon support materials useful in chromatography and their preparation
Assignee: Merck Patent GmbH
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Filing: 1979-01-23
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Granted: 1980-09-30
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Expires: 1999-01-23
Abstract
Abstract A process for preparing porous carbon support materials comprises treating activated carbon or coke, having a particle size of about 5 to about 50 μm, a specific surface area of about 10 to 1,000 m 2 /g, a hardness of at least about 95% attrition resistance, with solvent or solvents, and then heat treating the activated carbon or coke at a temperature of about 2,400-3,000° C. under an inert, gas atmosphere; said solvent or solvents affecting the mineral and organic impurities in the activated carbon or coke such that after said subsequent heat treatment, substantially all of said impurities are removed. A hard, mechanically stable, porous carbon support material consisting essentially of highly purified activated carbon, highly purified coke or a mixture thereof, said support material having a carbon content of at least 99%, a specific surface area of about 1 to about 5 m 2 /g and a particle size of about 5 to about 50 μm, may be prepared in this way.
Inventors
- 👤 Klaus Unger
- 👤 Heinz Gotz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:18
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/20; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/378
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
A process for preparing porous carbon support materials useful in chromatography, which comprises treating activated carbon or coke, having a particle size of about 5 to about 50 μm, a specific surface area of about 10 to about 1,000 m 2 /g, and a hardness of at least about 95% attrition resistance, with a solvent or solvents, and then heat treating the activated carbon or coke at a temperature of about 2,400°-3,000° C. under an inert, gas atmosphere; said solvent or solvents affecting the mineral and/or organic impurities in the activated carbon or coke, such that, after said subsequent heat treatment, substantially all of said impurities are removed.
Claim 2
Dependent Claim
108 words
A process for preparing porous carbon support materials useful in chromatography, which comprises treating activated carbon or coke, having a particle size of about 5 to about 50 μm, a specific surface area of about 10 to about 1,000 m 2 /g, and a hardness of at least about 95% attrition resistance, with a solvent or solvents, and then heat treating the activated carbon or coke at a temperature of about 2,400°-3,000° C. under an inert, gas atmosphere; said solvent or solvents affecting the mineral and/or organic impurities in the activated carbon or coke, such that, after said subsequent heat treatment, substantially all of said impurities are removed.
Claim 3
Dependent Claim
31 words
The process of claim 1, wherein the solvent treatment comprises extracting the activated carbon or coke with an aqueous acid or acids and then repeatedly evaporating after addition of hydrofluoric acid.
Claim 4
Dependent Claim
43 words
The process of claim 2, wherein the solvent treatment comprises extracting the activated carbon or coke 3-5 times with about 20% hydrochloric acid for a total of about 72 hours, and then evaporating to dryness about 3 times after addition of hydrofluoric acid.
Claim 5
Dependent Claim
64 words
A hard, mechanically stable, porous carbon support material useful in chromatography consisting essentially of highly purified activated carbon, highly purified coke, or a mixture thereof, said support material having a carbon content of at least 99%, a specific surface area of about 1 to about 5 m 2 /g a particle size of about 5 to about 50 μm and a graphitzed carbon surface.
Claim 6
Dependent Claim
64 words
A hard, mechanically stable, porous carbon support material useful in chromatography consisting essentially of highly purified activated carbon, highly purified coke, or a mixture thereof, said support material having a carbon content of at least 99%, a specific surface area of about 1 to about 5 m 2 /g a particle size of about 5 to about 50 μm and a graphitzed carbon surface.
Claim 7
Dependent Claim
40 words
The porous carbon support material of claim 1 having a carbon content of at least 99%, a specific surface area of about 1 to about 5 m 2 /g and a particle size of about 5 to about 50 μm.
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) | 1983-09-30 | 1984-03-31 | 1984-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-30 | 1988-03-31 | 1988-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-30 | 1992-03-31 | 1992-09-30 | $7700.00 | Window Closed / Lapsed |