Patent US2768145A successfully refreshed from Google Patents.
US2768145A
Expired / Lapsed
US
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Method of manufacturing silica alumina catalyst
Assignee: WR Grace and Co
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Filing: 1951-01-12
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Granted: 1956-10-23
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Expires: 1971-01-12
Abstract
No abstract record available.
Inventors
- 👤 Thomas O Tongue
- 👤 Leon L Baral
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:54
CPC Classifications
B; B01; B01J; B01J21/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
90 words
A METHOD OF PREPARING MICROSPHEROIDAL SILICAALUMINA CATALYSTS COMPRISING FORMING AN AQUEOUS ACIDREACTING SLURRY OF SILICA HYDROGEL, ADDING ALUMINUM SULFATE TO SAID SLURRY OF IMPREGNATE THE HYDROGEL PARTICLES THEREWITH, ADDING AQUEOUS AMMONIA TO SAID SLURRY TO PRECIPITATE HYDRATED ALUMINA, DEWATERING THE RESULTING SILICAALUMINA COMPOSITE, RE-SLURRYING SAID COMPOSITE, SPRAY DRYING THE RE-SLURRIED MATERIAL WITHOUT FURTHER WASHING TO A MOISTURE CONTENT OF ABOUT 3 TO 4%, WASHING THE SPRAY DRIED MATERIAL TO REMOVE SOLUBLE SALTS THEREFROM, AND CALCINING THE SALT-FREE MATERIAL TO FORM A CATALYST OF SILICA-ALUMINA MICROSPHERES HAVING AN ENHANCED ATTRITION RESISTANCE.
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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) | 1959-10-23 | 1960-04-23 | 1960-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-10-23 | 1964-04-23 | 1964-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-10-23 | 1968-04-23 | 1968-10-23 | $7700.00 | Window Closed / Lapsed |