Patent US2885261A successfully refreshed from Google Patents.
US2885261A
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US
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Improved process of removing zinc contaminants from sodium aluminate liquors
Assignee: Kaiser Aluminum and Chemical Corp
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Filing: 1956-07-02
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Granted: 1959-05-05
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Expires: 1976-07-02
Abstract
No abstract record available.
Inventors
- 👤 Adams Earl Walter
- 👤 Robert L Jeansonne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:08
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/20; C22B3/44; C22B3/46; C01; C01F; C01F7/00; C01F7/02; C01F7/46; C01F7/47; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
IN A CONTINOUS WET CAUSTIC ALUMINATE PROCESS FOR THE PRODUCTION OF ALUMINOUS ORES CONTAINING CAUSTIC-SOLUBLE ALUMINA AND CAUSTIC SOLUBLE ZINC IMPURITIES WHICH CONTAMINATE THE ULTIMATE ALUMINA PRODUCT, WHEREIN THE ORE IS DIGESTED IN CIRCULATING CAUSTIC ALUMINATE LIQUOR TO EXTRACT ALUMINA, AND ALUMINA IS RECOVERED FROM THE LIQUOR BY PRECIPITATION, THE IMPROVEMENT WHICH COMPRISES PRECIPTATING THE DISSOLVED ZINC FROM THE CAUSTIC ALUMINATE LIQUOR BY ADDING SODIUM SULPHIDE TO ABOUT A HALF OF THE CIRCULATING LIQUOR IN AMOUNTS SUFFICIENT TO PROVIDE A CONCENTRATION OF AT LEAST OF SODIUM SULPHIDE BASED ON THE TOTAL LIQUOR VOLUME, WITH THE UNTREATED PORTION OF SAID LIQUOR AND REMOVING THE INSOLUBLE ZINC SULPHIDE FORMED FROM THE LIQUOR PRIOR TO ALUMINA PRECIPITATION.
Claim 2
Dependent Claim
114 words
IN A CONTINOUS WET CAUSTIC ALUMINATE PROCESS FOR THE PRODUCTION OF ALUMINOUS ORES CONTAINING CAUSTIC-SOLUBLE ALUMINA AND CAUSTIC SOLUBLE ZINC IMPURITIES WHICH CONTAMINATE THE ULTIMATE ALUMINA PRODUCT, WHEREIN THE ORE IS DIGESTED IN CIRCULATING CAUSTIC ALUMINATE LIQUOR TO EXTRACT ALUMINA, AND ALUMINA IS RECOVERED FROM THE LIQUOR BY PRECIPITATION, THE IMPROVEMENT WHICH COMPRISES PRECIPTATING THE DISSOLVED ZINC FROM THE CAUSTIC ALUMINATE LIQUOR BY ADDING SODIUM SULPHIDE TO ABOUT A HALF OF THE CIRCULATING LIQUOR IN AMOUNTS SUFFICIENT TO PROVIDE A CONCENTRATION OF AT LEAST OF SODIUM SULPHIDE BASED ON THE TOTAL LIQUOR VOLUME, WITH THE UNTREATED PORTION OF SAID LIQUOR AND REMOVING THE INSOLUBLE ZINC SULPHIDE FORMED FROM THE LIQUOR PRIOR TO ALUMINA PRECIPITATION.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-05-04 | 1962-11-03 | 1963-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-05-04 | 1966-11-03 | 1967-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-05-04 | 1970-11-03 | 1971-05-05 | $7700.00 | Window Closed / Lapsed |