Patent US3243262A successfully refreshed from Google Patents.
US3243262A
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Process for preparing microspheroidal silica
Assignee: WR Grace and Co
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Filing: 1963-02-18
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Granted: 1966-03-29
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Expires: 1983-02-18
Abstract
No abstract record available.
Inventors
- 👤 Carr Brownell
- 👤 Hanson L Guidry
- 👤 James R Hyde
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:51
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/152; C01B33/154
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
129 words
A PROCESS FOR PREPARING MICROSPHEROIDAL SILICA HAVING A SURFACE AREA OF ABOUT 300 TO 1000M.2/G. AND A PORE VOLUME OF ABOUT 0.5 TO 1.25 CC./G., WHICH COMPRISES (A) DILUTING A SODIUM SILICATE SOLUTION TO A SILICA CONTENT OF ABOUT 3 TO 8%, (B) REACTING THE SILICATE IN THE SOLUTION WITH CARBON DIOXIDE TO FORM A SILICA GEL, (C) AGING THE GELLED SILICATE IN THE REACTION MIXTURE AT A TEMPERATURE OF AT LEAST 100*F. FOR A PERIOD OF ABOUT 30 MINUTES TO 2 HOURS, (D) ADDING SULFURIC ACID TO THE REACTION MIXTURE CONTAINING THE AGED SILICA GEL IN A QUANTITY SUFFICIENT TO ADJUST THE PH TO ABOUT 4.5 TO 8.0, (E) SPRAY DRYING THE REACTION MIXTURE, (F) WASHING TO REMOVE SOLUBLE IMPURITIES, (G) AND DRYING AND RECOVERING THE PRODUCT SILICA.
Claim 2
Dependent Claim
129 words
A PROCESS FOR PREPARING MICROSPHEROIDAL SILICA HAVING A SURFACE AREA OF ABOUT 300 TO 1000M.2/G. AND A PORE VOLUME OF ABOUT 0.5 TO 1.25 CC./G., WHICH COMPRISES (A) DILUTING A SODIUM SILICATE SOLUTION TO A SILICA CONTENT OF ABOUT 3 TO 8%, (B) REACTING THE SILICATE IN THE SOLUTION WITH CARBON DIOXIDE TO FORM A SILICA GEL, (C) AGING THE GELLED SILICATE IN THE REACTION MIXTURE AT A TEMPERATURE OF AT LEAST 100*F. FOR A PERIOD OF ABOUT 30 MINUTES TO 2 HOURS, (D) ADDING SULFURIC ACID TO THE REACTION MIXTURE CONTAINING THE AGED SILICA GEL IN A QUANTITY SUFFICIENT TO ADJUST THE PH TO ABOUT 4.5 TO 8.0, (E) SPRAY DRYING THE REACTION MIXTURE, (F) WASHING TO REMOVE SOLUBLE IMPURITIES, (G) AND DRYING AND RECOVERING THE PRODUCT SILICA.
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) | 1969-03-28 | 1969-09-27 | 1970-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-28 | 1973-09-27 | 1974-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-28 | 1977-09-27 | 1978-03-29 | $7700.00 | Window Closed / Lapsed |