US3728273A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of recovering chromium and barium values from waste barium chromate
Assignee: Honeywell International Inc
•
Filing: 1971-09-27
•
Granted: 1973-04-17
•
Expires: 1991-09-27
Abstract
Abstract RECOVERY OF CHROMINUM VALUES AND A RE-USABLE BARIUM CARBONATE COMPOSITON FROM BARIUM CHROMATE WASTE TREATMENT SLUDGES, BY DIGESTION IN AN AQUEOUS MEDIUM WITH AT LEAST 100% STOICHIOMETIC EXCESS OF SODIUM CARBONATE, AT TEMPERATURE BETWEEN 80 AND 250*C. A SOLUTION OF SODIUM CHROMATE "YELLOW LIQUID" IS SEPRARATED FROM THE SOLID BARIUM CARBONATE, A PORTION OF WHICH IS DISSOLVED IN NITRIC ACID AT A PH OF 4.5 TO 5.5 AS A MEANS OF PURGING INSOLUBLE IMPURITIES. THE SEPARATED BARIUM NITRATE IS RECOMBINED WITH THE BALANCE OF THE BARIUM CARBONATE TO PROVIDE THE RE-USABLE BARIUM CARBONATE COMPOSITION.
Inventors
- 👤 C Bruen
- 👤 C Wamser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:22
CPC Classifications
C; C01; C01G; C01G37/00; C01G37/14; C01F; C01F11/00; C01F11/18; C01F11/186; C01F11/188
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |