US3767378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of rutile and iron from ilmenite
Assignee: United States Department of the Interior
•
Filing: 1972-01-05
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Granted: 1973-10-23
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Expires: 1992-01-05
Abstract
Abstract Ilmenite is treated with a reducing agent to selectively reduce iron oxide to metallic iron. The product is then treated with carbon monoxide in the presence of ammonium polysulfide solution to form iron carbonyl, which is removed by volatilization leaving rutile. The iron carbonyl is then decomposed to produce metallic iron.
Inventors
- 👤 A Cochran
- 👤 A Starliper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:17
CPC Classifications
C; C21; C21B; C21B13/00; C21B13/006; C01; C01G; C01G49/00; C01G49/16; C22; C22B; C22B34/00; C22B34/10; C22B34/12; C22B34/1204; Y; Y02; Y02P; Y02P10/00; Y02P10/10; Y02P10/134
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
23 words
The method of claim 1 in which the reduction is preceded by an oxidation step to convert any ferrous iron to ferric iron.
Claim 2
Dependent Claim
13 words
The method of claim 1 in which the reduction is accomplished with hydrogen.
Claim 3
Dependent Claim
13 words
The method of claim 1 in which the reduction is accomplished with coke.
Claim 4
Dependent Claim
19 words
The method of claim 1 in which the carbonyl is decomposed at a temperature of about 280* to 350*C.
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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) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |