US3560153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Conversion of ilmenite to rutile utilizing sulfur dioxide
Assignee: Bechtel International Corp
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Filing: 1969-02-27
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Granted: 1971-02-02
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Expires: 1989-02-27
Abstract
Abstract ILMENITE IS CONVERTED TO RUTILE BY HEATING THE ILMENITE IN THE PRESENCE OF SULFUR DIOXIDE AND A REDUCTANT TO SULFIDIZE THE IRON CONTENT FOLLOWED BY LEACHING OF THE SULFIDIZED ILMENITE WITH SULFUROUS ACID. IN A SUBSEQUENT ROASTING STEP, SULFUR DIOXIDE IS RELEASED WHICH CAN BE RECYCLED TO THE SULFIDIZING STEP.
Inventors
- 👤 Nevin K Hiester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:16
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/10; C22B34/12; C22B34/1204
Claims Analysis
Total Claims: 0
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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) | 1974-02-01 | 1974-08-03 | 1975-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-01 | 1978-08-03 | 1979-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-01 | 1982-08-03 | 1983-02-02 | $7700.00 | Window Closed / Lapsed |