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US2434424A
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Plural stage extractive distillation with inverse solvents
Assignee: Shell Development Co
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Filing: 1942-03-10
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Granted: 1948-01-13
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Expires: 1962-03-10
Abstract
No abstract record available.
Inventors
- 👤 Rupert C Morris
- 👤 Theodore W Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:09
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/05; C07C7/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1882978A
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US1884241A
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US1948777A
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US1912349A
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US2123642A
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US2109157A
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US2220016A
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US2113965A
Cited
US2246982A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-01-12 | 1951-07-14 | 1952-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-01-12 | 1955-07-14 | 1956-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-01-12 | 1959-07-14 | 1960-01-13 | $7700.00 | Window Closed / Lapsed |