Patent US4458022A successfully refreshed from Google Patents.
US4458022A
Expired / Lapsed
US
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Process for manufacturing molecular sieving carbon
Assignee: Kuraray Chemical Co Ltd
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Filing: 1983-05-17
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Granted: 1984-07-03
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Expires: 2003-05-17
Abstract
Abstract A process for manufacturing molecular sieving carbon is disclosed, wherein pelletized charcoal made of coconut shell charcoal powder and coal tar is washed with dilute mineral acid solution, then a specified amount of coal tar is added, penetrated therein, followed by heat treatment under a particular range of temperature, and cooling in inert gas.
Inventors
- 👤 Takushi Ohsaki
- 👤 Susumu Abe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:39
CPC Classifications
C; C01; C01B; C01B32/00; C01B32/30; C01B32/306
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
A process for manufacturing molecular sieving carbon comprising the steps of: (a) adding coal tar pitch, coal tar, or a combination thereof to powdered coconut shell charcoal as a binder, (b) pelletizing said mixture and carbonizing the same at about 750° C.-900° C., (c) immersing the pellets in a dilute mineral acid solution, (d) drying the adequately washed pellets, (e) adding about 1-3% coal tar pitch, coal tar, or a combination thereof to the pellets, (f) heating the pellets to about 200° C.-400° C., (g) heating the pellets to about 950° C.-1000° C. for about 10-60 minutes, and (h) cooling the pellets in an inert gas.
Claim 2
Dependent Claim
106 words
A process for manufacturing molecular sieving carbon comprising the steps of: (a) adding coal tar pitch, coal tar, or a combination thereof to powdered coconut shell charcoal as a binder, (b) pelletizing said mixture and carbonizing the same at about 750° C.-900° C., (c) immersing the pellets in a dilute mineral acid solution, (d) drying the adequately washed pellets, (e) adding about 1-3% coal tar pitch, coal tar, or a combination thereof to the pellets, (f) heating the pellets to about 200° C.-400° C., (g) heating the pellets to about 950° C.-1000° C. for about 10-60 minutes, and (h) cooling the pellets in an inert gas.
Claim 3
Dependent Claim
29 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the rate of temperature increase between steps (f) and (g) of claim 1 is held substantially constant.
Claim 4
Dependent Claim
30 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the heat treatment described in step (g) of claim 1 is between about 950° C. and 970° C.
Claim 5
Dependent Claim
28 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the heat treatment described in step (g) of claim 1 is maintained for about 20-30 minutes.
Claim 6
Dependent Claim
28 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the cooling temperature used in step (h) of claim 1 is about 300° C. or less.
Claim 7
Dependent Claim
30 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the dilute mineral acid solution used in step (c) of claim 1 is about 0.4 to 0.6N HCL.
Claim 8
Dependent Claim
27 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the heating described in step (f) of claim 1 is effectuated in a rotary kiln.
Claim 9
Dependent Claim
27 words
A process for manufacturing molecular sieving carbon according to claim 1 wherein the heating described in step (g) of claim 1 is effectuated in an electric furnace.
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) | 1987-07-03 | 1988-01-02 | 1988-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-03 | 1992-01-02 | 1992-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-03 | 1996-01-02 | 1996-07-03 | $7700.00 | Window Closed / Lapsed |