US2921839A
Expired / Lapsed
US
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Silica precipitation method
Assignee: Columbia Southern Chemical Corp
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Filing: 1955-12-23
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Granted: 1960-01-19
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Expires: 1975-12-23
Abstract
No abstract record available.
Inventors
- 👤 Hartien S Ritter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:49
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; C01B33/187; C01B33/16; C01B33/166; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/50; C01P2004/60; C01P2004/61
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
117 words
A METHOD OF PRODUCING FINELY DIVIDED GRANULAR SILICA OF SUBSTANTIALLY UNIFORM PARTICLE SIZE WHICH COMPRISES, ADDING AN AQUEOUS ALKALI METAL SILICATE SOLUTION TO A NEUTRAL WATER-IMMISCIBLE LIQUID, AGITATING THE MIXTURE OF SILICATE SOLUTION AND WATER-IMMISCIBLE LIQUID TO DISPERSE SAID SILICATE SOLUTION IN DROPLETS OF SUBSTANTIALLY UNIFORM PARTICLE SIZE UNIFORMLY THROUGHTOUT SAID LIQUID, AND THEREAFTER, WHILE CONTINUING SAID AGITATION, INTRODUCING A WATER-SOLUBLE ACID CAPABLE OF PRECIPITATING SILICA FROM SAID SILICATE SOLUTION INTO SAID AGITATED DISPERSION TO PROVIDE FOR A REACTION BETWEEN SAID ACID AND SAID AQUEOUS ALKALI METAL SILICATE DROPLETS AT THE INTERFACE BETWEEN SAID DROPLETS AND SAID WATER-IMMISCIBLE LIQUID, DISCONTINUING SAID AGITATION, SEPARATING SAID WATER-IMMISCIBLE LIQUID AND RECOVERING SAID GRANULAR PARTICLES OF SILICA FORMED BY SAID REACTION.
Claim 2
Independent Claim
117 words
A METHOD OF PRODUCING FINELY DIVIDED GRANULAR SILICA OF SUBSTANTIALLY UNIFORM PARTICLE SIZE WHICH COMPRISES, ADDING AN AQUEOUS ALKALI METAL SILICATE SOLUTION TO A NEUTRAL WATER-IMMISCIBLE LIQUID, AGITATING THE MIXTURE OF SILICATE SOLUTION AND WATER-IMMISCIBLE LIQUID TO DISPERSE SAID SILICATE SOLUTION IN DROPLETS OF SUBSTANTIALLY UNIFORM PARTICLE SIZE UNIFORMLY THROUGHTOUT SAID LIQUID, AND THEREAFTER, WHILE CONTINUING SAID AGITATION, INTRODUCING A WATER-SOLUBLE ACID CAPABLE OF PRECIPITATING SILICA FROM SAID SILICATE SOLUTION INTO SAID AGITATED DISPERSION TO PROVIDE FOR A REACTION BETWEEN SAID ACID AND SAID AQUEOUS ALKALI METAL SILICATE DROPLETS AT THE INTERFACE BETWEEN SAID DROPLETS AND SAID WATER-IMMISCIBLE LIQUID, DISCONTINUING SAID AGITATION, SEPARATING SAID WATER-IMMISCIBLE LIQUID AND RECOVERING SAID GRANULAR PARTICLES OF SILICA FORMED BY SAID REACTION.
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) | 1963-01-18 | 1963-07-20 | 1964-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-18 | 1967-07-20 | 1968-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-18 | 1971-07-20 | 1972-01-19 | $7700.00 | Window Closed / Lapsed |