US3684438A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of phosphoric acid
Assignee: FMC Corp
•
Filing: 1970-11-05
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Granted: 1972-08-15
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Expires: 1990-11-05
Abstract
Abstract A PROCESS FOR PURIFYING WET PHOSPHORIC ACID OR RAFFINATE ACID RESULTING FROM THE PURIFICATION OF WET ACID, SAID PROCESS COMPRISING MIXING SAID IMPURE ACID WITH A BLEND OF METHYL AND ISOPROPYL ALCOHOLS IN ORDER TO PRECIPITATE THE IMPURITIES AND RECOVER THE PURIFIED ACID.
Inventors
- 👤 Robert Joseph Gleason
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:21
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/16; C01B25/18; C01B25/234
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) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |