Patent US3203760A successfully refreshed from Google Patents.
US3203760A
Expired / Lapsed
US
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Process for preparing silica gel
Assignee: WR Grace and Co
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Filing: 1962-12-17
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Granted: 1965-08-31
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Expires: 1982-12-17
Abstract
No abstract record available.
Inventors
- 👤 Milton E Winyall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:47
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/152; C01B33/154; C01B33/18; C01B33/181; C01B33/187; C01P; C01P2004/00; C01P2004/51; C01P2004/60; C01P2004/61; C01P2006/00; C01P2006/12; C01P2006/14; C01P2006/80
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
144 words
A PROCESS FOR PREPARING A SILICA GEL WHEREIN ABOUT 80% OF THE PARTICLES HAVE A PARTICLE SIZE BELOW 80 MICRONS AAND A SURFACE AREA OF ABOUT 100 TO 250 M.2/G. WHICH COMPRISES THE STEPS OF: (A) DILUTING A SODIUM SILICATE SOLUTION TO ABOUT 6* BE., (B) ADJUSTING THE PH OF THE SOLUTION TO ABOUT 2.9 TO 3.5 WITH A MINERAL ACID SELECTED FROM THE GROUP CONSISTING OF HYDROCHLORIC, NITRIC AND SULFURIC ACIDS, (C) AGING THE RESULTING SOL, (D) SPRAY DRYING SAID SOL IN A SPRAY DRIER OPERATED AT AN INLET TEMPERATURE OF ABOUT 900*F. AND AN OUTLET TEMPERATURE OF ABOUT 300*F., (E) WASHING THE RESULTING PARTICLES WITH A SOLUTION OF SULFURIC ACID IN ABOUT AT 6% CONCENTRATION, FOLLOWED BY A WATER WASH AND A WASH WITH A SOLUTION OF AMMONIUM SULFATE IN A CONCENTRATION OF ABOUT 2%, (F) DRYING AND RECOVERING THE PRODUCT SILICA.
Claim 2
Dependent Claim
144 words
A PROCESS FOR PREPARING A SILICA GEL WHEREIN ABOUT 80% OF THE PARTICLES HAVE A PARTICLE SIZE BELOW 80 MICRONS AAND A SURFACE AREA OF ABOUT 100 TO 250 M.2/G. WHICH COMPRISES THE STEPS OF: (A) DILUTING A SODIUM SILICATE SOLUTION TO ABOUT 6* BE., (B) ADJUSTING THE PH OF THE SOLUTION TO ABOUT 2.9 TO 3.5 WITH A MINERAL ACID SELECTED FROM THE GROUP CONSISTING OF HYDROCHLORIC, NITRIC AND SULFURIC ACIDS, (C) AGING THE RESULTING SOL, (D) SPRAY DRYING SAID SOL IN A SPRAY DRIER OPERATED AT AN INLET TEMPERATURE OF ABOUT 900*F. AND AN OUTLET TEMPERATURE OF ABOUT 300*F., (E) WASHING THE RESULTING PARTICLES WITH A SOLUTION OF SULFURIC ACID IN ABOUT AT 6% CONCENTRATION, FOLLOWED BY A WATER WASH AND A WASH WITH A SOLUTION OF AMMONIUM SULFATE IN A CONCENTRATION OF ABOUT 2%, (F) DRYING AND RECOVERING THE PRODUCT SILICA.
References Cited (Backward Citations)
US1748315A
Cited
US1843576A
Cited
US1900859A
Cited
US2699376A
Cited
US2871099A
Cited
US3041140A
Cited
US3070426A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-08-30 | 1969-03-01 | 1969-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-30 | 1973-03-01 | 1973-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-30 | 1977-03-01 | 1977-08-31 | $7700.00 | Window Closed / Lapsed |