US3813852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of recovering fluorine from waste gases
Assignee: Elkem ASA
•
Filing: 1973-03-19
•
Granted: 1974-06-04
•
Expires: 1993-03-19
Abstract
Abstract Fluorine from waste gases is recovered by contacting the gases with aluminum oxide in the presence of steam. The steam increases the adsorption rate of the aluminum oxide thereby improving fluorine recovery.
Inventors
- 👤 F Steineke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:30
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/48; C01F7/50; B; B01; B01D; B01D53/00; B01D53/02; B01D53/06; B01D53/10; B01D53/12; B01D53/34; B01D53/46; B01D53/68
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
14 words
The method of claim 1 wherein the minimum temperature during the contacting is 100*C.
Claim 2
Dependent Claim
14 words
The method of claim 1 wherein the maximum temperature during the contacting is 600*C.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the maximum temperature during the contacting is 500*C.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein the maximum temperature during the contacting is 300*C.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein the water content does not exceed 25%.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein at least part of the water is supplied as moisture in the aluminum oxide.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein at least part of the water is supplied by mixing dry fluorine-containing gases with moist fluorine-containing gases.
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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |