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US3428575A
Expired / Lapsed
US
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Alkali on a support promoted by iron or iron and antimony in sulfur dioxide removal
Assignee: Shell USA Inc
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Filing: 1967-05-15
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Granted: 1969-02-18
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Expires: 1987-05-15
Abstract
No abstract record available.
Inventors
- 👤 Franciscus W Pijpers
- 👤 Maria M J J Starmans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:33
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/508; C; C01; C01B; C01B17/00; C01B17/48; C01B17/50; C01B17/60
Claims Analysis
Total Claims: 0
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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) | 1972-02-18 | 1972-08-19 | 1973-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-18 | 1976-08-19 | 1977-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-18 | 1980-08-19 | 1981-02-18 | $7700.00 | Window Closed / Lapsed |