US3764561A
Expired / Lapsed
US
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Activated carbon from admixture of coking coal and inorganic potassium salts
Assignee: Takeda Pharmaceutical Co Ltd
•
Filing: 1971-03-09
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Granted: 1973-10-09
•
Expires: 1991-03-09
Abstract
Abstract Coking coal is admixed with a small but critical amount of inorganic potassium salt, followed by subjecting the mixture to a carbonization to produce a coke which is convertible to activated carbon showing a strong absorption capacity in gas phase.
Inventors
- 👤 H Nishino
- 👤 H Kubo
- 👤 H Ichikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:43
CPC Classifications
C; C01; C01B; C01B32/00; C01B32/30; C01B32/312; C01B32/342; C01B32/348
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
43 words
The activated carbon of claim 1, wherein the inorganic potassium salt is a member selected from the class consisting of potassium hydroxide, potassium carbonate, potassium bicarbonate, potassium sulfate, potassium nitrate, potassium chloride, potassium bromide, potassium iodide, potassium permanganate, potassium cyanide and potassium bichromate.
Claim 2
Dependent Claim
14 words
The activated carbon of claim 1, wherein the inorganic potasSium salt is potassium carbonate.
Claim 3
Dependent Claim
14 words
The activated carbon of claim 1, wherein the inorganic potassium salt is potassium sulfate.
Claim 4
Dependent Claim
14 words
The activated carbon of claim 1, wherein the inorganic potassium salt is potassium hydroxide.
Claim 5
Dependent Claim
22 words
The activated carbon of claim 1 wherein said admixture of coking coal and inorganic potassium salt is carbonized at 450* to 700*C.
References Cited (Backward Citations)
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DE500981C
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GB291043A
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DE506522C
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GB588811A
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US2894914A
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US3340316A
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US3329626A
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US3492244A
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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) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |