Patent US3575711A successfully refreshed from Google Patents.
US3575711A
Expired / Lapsed
US
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Process for pickling and regenerating
Assignee: Individual
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Filing: 1968-12-26
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Granted: 1971-04-20
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Expires: 1988-12-26
Abstract
Abstract A PROCESS FOR PICKLING IRON AND STEEL ARTICLES AND FOR REGENERATING USED PICKLE LIQUOR FOR RE-USE IN WHICH THE ARTICLES ARE PICKLED IN HOT AQUEOUS SULPHURIC ACID BATH, THE BATH IS ACTIVELY AGITATED BY AIR INJECTION TO PROMOTE EFFICIENT HEATING AND MAINTAIN UNIFORM CONDITIONS THROUGHOUT THE BATH. USED SOLUTION CONTAINING 8% TO 12% BY WEIGHT DISSOLVED IRON IS REMOVED FROM THE BATH AND COOLED TO PRECIPITATE DISSOLVED IRON AS FES04 7H20. IRONFREE SOLUTION IS RETURNED TO THE BATH.
Inventors
- 👤 David Krofchak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:55
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/36; C01; C01G; C01G49/00; C01G49/14; C23G1/02; C23G1/08; C23G1/081
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) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |