Patent US2455803A successfully refreshed from Google Patents.
US2455803A
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Extractive distillation process
Assignee: Shell Development Co
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Filing: 1944-02-11
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Granted: 1948-12-07
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Expires: 1964-02-11
Abstract
No abstract record available.
Inventors
- 👤 Gino J Pierotti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:09
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)
US2434796A
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US1474216A
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US2162963A
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US2366360A
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US2396302A
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US2290636A
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US2325329A
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US2350584A
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US2360861A
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US2360859A
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US2357028A
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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) | 1951-12-07 | 1952-06-07 | 1952-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-12-07 | 1956-06-07 | 1956-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-12-07 | 1960-06-07 | 1960-12-07 | $7700.00 | Window Closed / Lapsed |