Patent US3681259A successfully refreshed from Google Patents.
US3681259A
Expired / Lapsed
US
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Manufacture of low bulk density-high strength spherical chromia-alumina particles
Assignee: Honeywell UOP LLC
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Filing: 1969-12-29
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Granted: 1972-08-01
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Expires: 1989-12-29
Abstract
Abstract LOW DENSITY CHROMIA-ALUMINA GEL SPHERES OF IMPROVED CRUSHING STRENGHT ARE PREPARED BY THE OIL-DROP METHOD UTILIZING A DROPPING MIXTURE COMPRISING A CHROMIA-ALUMINA SOL AND HEXAMETHYLENETERAMINE, SAID DROPPING MIXTURE HAVING A METALS/CHLORIDE WEIGHT RATIO OF FROM ABOUT 1:1 TO ABOUT 1.5:1, A HEXAMETHYLENETETRAMINE/CHLORIDE MOLE RATIO OF FROM ABOUT 1.1:4 TO ABOUT 1.65:4 AND A CHROMIUMALUMINUM METALS CONTENT OF FROM ABOUT 7 TO ABOUT 10 WEIGHT PERCENT. AFTER DROPPING, THE SPHERS ARE PRESSURE AGED AT A TEMPRATURE OF FROM ABOUT 240* TO ABOUT 500* F. FOR A PERIOD OF FROM ABOUT 1 TO ABOUT 5 HOURS, AND ARE THEN WASHED, DRIED AND CALCINED.
Inventors
- 👤 Kenneth D Vesely
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:45
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/16; B01J23/24; B01J23/26; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/944; B01J2/00; B01J2/02; B01J2/06; B01J2/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |