Patent US3070426A successfully refreshed from Google Patents.
US3070426A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing low surface area silica
Assignee: WR Grace and Co
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Filing: 1959-08-11
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Granted: 1962-12-25
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Expires: 1979-08-11
Abstract
No abstract record available.
Inventors
- 👤 Milton E Winyall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:01
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; C01B33/187; C01P; C01P2004/00; C01P2004/51; C01P2004/60; C01P2004/61; C01P2006/00; C01P2006/12; C01P2006/14; C01P2006/16; C01P2006/80
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
A PROCESS FOR PREPARING A SILICA THEREIN GREATER THAN 80% OF THE PARTICULES HAVE A PARTICULE SIZE BELOW 80 MICRONS, AND HAVING A SURFACE AREA OF 10-50M2./G., CONSISTING ESSENTIALY OF SPRAY DRYING AN AQUEOUS SOLUTION OF SODIUM SILICATE HAVING AN SIO2 TO NA2O WEIGHT RATIO OF 1 TO 1 TO 3.4 TO 1 IN A SPRAY DRYER OPERATED AT AN INLET TEMPERATURE OF ABOUT 900*F. AND AN OUTLET TEPERATURE OF ABOUT 300*F., THEREAFTER TREATING THE SPRAY DRIED SILICSTE PARTICULES WITH VIGOROUS AGITATION WITH A QUANTITY OF A 1% SOLUTIONN OF A STRONG MINERAL ACID SELECTED FROM THE GROUP CONSISTING OF SULFURIC, HYDROCHLORIDE AND NITRIC ACIDS SUFFICIENT TO NEUTRALIZED THE SODA IN THE DRIED PARTICLES, WASHING THE TREATED PARTICULES, FIRST WITH WATER AND THEN WITH AN 0.125% AMMONIUM SULFATE SOLUTION,DRYING AND RECOVERING THE PRODUCT SILICA.
Claim 2
Dependent Claim
134 words
A PROCESS FOR PREPARING A SILICA THEREIN GREATER THAN 80% OF THE PARTICULES HAVE A PARTICULE SIZE BELOW 80 MICRONS, AND HAVING A SURFACE AREA OF 10-50M2./G., CONSISTING ESSENTIALY OF SPRAY DRYING AN AQUEOUS SOLUTION OF SODIUM SILICATE HAVING AN SIO2 TO NA2O WEIGHT RATIO OF 1 TO 1 TO 3.4 TO 1 IN A SPRAY DRYER OPERATED AT AN INLET TEMPERATURE OF ABOUT 900*F. AND AN OUTLET TEPERATURE OF ABOUT 300*F., THEREAFTER TREATING THE SPRAY DRIED SILICSTE PARTICULES WITH VIGOROUS AGITATION WITH A QUANTITY OF A 1% SOLUTIONN OF A STRONG MINERAL ACID SELECTED FROM THE GROUP CONSISTING OF SULFURIC, HYDROCHLORIDE AND NITRIC ACIDS SUFFICIENT TO NEUTRALIZED THE SODA IN THE DRIED PARTICLES, WASHING THE TREATED PARTICULES, FIRST WITH WATER AND THEN WITH AN 0.125% AMMONIUM SULFATE SOLUTION,DRYING AND RECOVERING THE PRODUCT SILICA.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-12-24 | 1966-06-25 | 1966-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-12-24 | 1970-06-25 | 1970-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-12-24 | 1974-06-25 | 1974-12-25 | $7700.00 | Window Closed / Lapsed |