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US3070426A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing low surface area silica

Assignee: WR Grace and Co
•
Filing: 1959-08-11
•
Granted: 1962-12-25
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Expires: 1979-08-11
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Abstract

No abstract record available.

Inventors

  • 👤 Milton E Winyall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 00:50
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.

References Cited (Backward Citations)

US1077950A Cited
US1739305A Cited
US1665264A Cited
US1819354A Cited
US1843576A Cited
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GB745822A Cited
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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

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