Patent US2576464A successfully refreshed from Google Patents.
US2576464A
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Froth flotation of siliceous impurities from cellulose
Assignee: Hercules Powder Co
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Filing: 1949-08-05
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Granted: 1951-11-27
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Expires: 1969-08-05
Abstract
No abstract record available.
Inventors
- 👤 Langmeier Arthur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:42
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/02; Y; Y10; Y10S; Y10S162/00; Y10S162/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
75 words
IN THE PURIFICATION OF A CELLULOSIC MATERIAL CONTAINING SILICEOUS IMPURITIES, THE PROCESS WHICH IN COMBINATION COMPRISES FORMING A DILUTE AQUEOUS SLURRY OF THE CELULOSIC MATERIAL, DISPERSING IN THE SLURRY A CATIONIC SURFACE-ACTIVE FLOTATION AGENT FOR THE SILICEOUS IMPURITIES AND A SURFACE TENSION DEPRESSANT FOR THE WATER, AGITATING AND AERATING THE SYSTEM THUS FORMED, CONTINUOUSLY REMOVING FROTH FROM ON THE SURFACE OF THE SYSTEM DURING AGITATION AND AERATION, AND SEPARATING PURIFIED CELLULOSIC MATERIAL FROM THE SYSTEM.
Claim 2
Dependent Claim
75 words
IN THE PURIFICATION OF A CELLULOSIC MATERIAL CONTAINING SILICEOUS IMPURITIES, THE PROCESS WHICH IN COMBINATION COMPRISES FORMING A DILUTE AQUEOUS SLURRY OF THE CELULOSIC MATERIAL, DISPERSING IN THE SLURRY A CATIONIC SURFACE-ACTIVE FLOTATION AGENT FOR THE SILICEOUS IMPURITIES AND A SURFACE TENSION DEPRESSANT FOR THE WATER, AGITATING AND AERATING THE SYSTEM THUS FORMED, CONTINUOUSLY REMOVING FROTH FROM ON THE SURFACE OF THE SYSTEM DURING AGITATION AND AERATION, AND SEPARATING PURIFIED CELLULOSIC MATERIAL FROM THE SYSTEM.
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) | 1954-11-26 | 1955-05-28 | 1955-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-26 | 1959-05-28 | 1959-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-26 | 1963-05-28 | 1963-11-27 | $7700.00 | Window Closed / Lapsed |