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US3531376A
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Purification of acetone by extractive distillation and rectification with simultaneous alkali-containing acetone solution contact and halogen impurity side stream removal
Assignee: Mitsubishi Chemical Corp
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Filing: 1968-12-23
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Granted: 1970-09-29
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Expires: 1988-12-23
Abstract
No abstract record available.
Inventors
- 👤 Shigehiko Minoda
- 👤 Tokuzo Shimizu
- 👤 Takeyoshi Matsumoto
- 👤 Toshihiro Maeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:17
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/78; C07C45/81; C07C45/82; B; B01; B01D; B01D3/00; B01D3/14; B01D3/143; B01D3/146; C07C45/83; Y; Y10; Y10S; Y10S203/00; Y10S203/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2238016A
Cited
US2669541A
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US2906676A
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US2971894A
Cited
US3265592A
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US3330741A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-09-28 | 1974-03-30 | 1974-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-28 | 1978-03-30 | 1978-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-28 | 1982-03-30 | 1982-09-29 | $7700.00 | Window Closed / Lapsed |