US2839475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of silica-containing catalysts of high pore diameter
Assignee: Wyeth Holdings LLC
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Filing: 1955-04-08
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Granted: 1958-06-17
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Expires: 1975-04-08
Abstract
No abstract record available.
Inventors
- 👤 William B Innes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:08
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/12; C; C10; C10G; C10G11/00; C10G11/02; C10G11/04; Y; Y10; Y10S; Y10S502/00; Y10S502/50; Y10S502/503; Y10S502/504
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
79 words
A METHOD OF PRODUCING SILICA GEL CATALYSTS OF HIGH PORE DIAMETER AND HIGH PORE VOLUME HAVING GOOD ATTRITION RESISTANCE WHICH COMPRISES FORMING A HYDRATED SILICA GEL CAPABLE OF HARDENING TO A DRIED GEL OF HIGH PORE VOLUME BY ACIDIFYING AN AQUEOUS SOLUTION OF COMMERCIAL ALKALI METAL SILICATE AT A TEMPERATURE BETWEEN ABOUT 60* AND 90*C. DURING A TIME OF ABOUT 20-35 MINUTES, IMPREGNATING THE RESULTING GEL WITH AN ACTIVATING METAL OXIDE, AND DRYING AND HARDENING THE RESULTING ACTIVATED GEL.
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) | 1961-06-16 | 1961-12-16 | 1962-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-06-16 | 1965-12-16 | 1966-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-06-16 | 1969-12-16 | 1970-06-17 | $7700.00 | Window Closed / Lapsed |