US3557020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hci or hbr vapor carbonization of vegetable material in the manufacture of activated carbon
Assignee: National Institute of Advanced Industrial Science and Technology
•
Filing: 1968-01-11
•
Granted: 1971-01-19
•
Expires: 1988-01-11
Abstract
Abstract WOOD OR OTHER VEGETABLE MATERIAL HAVING A NON-UNIFORM SHAPE SUCH AS SHAPELESS PARTICLE POWDER, FLAKY POWDER, CHIP AND THE OTHERS IS CARBONIZED IN AN ACIDIC ATMOSPHERE CONTAINING VAPOR OR GAS OF HYDROCHLORIC OR HYDROBROMIC ACID OR ITS ANHYDRIDE FOR 10 MINUTES TO 10 HOURS AT A TEMPERATURE OF 80-1200* C. TO OBTAIN ACTIVATED CARBON OF SUPERIOR ADSORPTION ACTIVITY IN VERY HIGH YIELDS. IF DESIRED, THE ACTIVATED CARBON SO OBTAINED IS HEATED FURTHER IN AN ATMOSPHERE CONTAINING AN OXIDIZING GAS SUCH AS STEAM, CARBON DIOXIDE GAS OR AIR, OR IN AN INERT ATMOSPHERE TO IMPROVE THE ADSORPTION ACTIVITY OF SAID CARBON.
Inventors
- 👤 Akio Shindo
- 👤 Isao Souma
- 👤 Yoichiro Nakanishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:54
CPC Classifications
C; C01; C01B; C01B32/00; C01B32/30; C01B32/312; C01B32/336
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |