US2969349A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of polymerization catalyst
Assignee: Phillips Petroleum Co
•
Filing: 1957-10-09
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Granted: 1961-01-24
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Expires: 1977-10-09
Abstract
No abstract record available.
Inventors
- 👤 Frederick L Stoller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:20
CPC Classifications
C; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
125 words
IN A PROCESS IN WHICH ETHYLENE IS CONVERTED TO NORMALLY SOLID POLYMER IN THE PRESENCE OF A CHROMIUM OXIDE CATALYST ACTIVE FOR THIS CONVERSION, THE POLYMERIZATION BEING CONDUCTED IN THE PRESENCE OF A DILUENT PARAFFINIC HYDROCARBON HAVING FROM 3 TO 12 CARBON ATOMS PER MOLECULE AND AN EFFLUENT CONTAINING SAID POLYMER DISSOLVED IN SAID DILUENT AND SAID CATALYST IN SUSPENSION IN SAID SOLUTION IS THEN PASSED TO A CENTRIFUGING ZONE WHEREIN SAID CATALYST IS SEPARATED FROM SAID SOLUTION BY CENTRIFUGATION, THE IMPROVEMENT WHICH COMPRISES PASSING SUPERHEATED VAPOR OF THE SAME DILUENT HYDROCARBON INTO SAID CENTRIFUGING ZONE AND THEREBY MAINTAINING A PRESSURE IN SAID ZONE EXCEEDING THE VAPOR PRESSURE OF SAID SOLUTION AND MAINTAINING SAID CENTRIFUGING ZONE AT A TEMPERATURE IN THE RANGE 200 TO 400*F.
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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) | 1964-01-24 | 1964-07-25 | 1965-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-01-24 | 1968-07-25 | 1969-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-01-24 | 1972-07-25 | 1973-01-24 | $7700.00 | Window Closed / Lapsed |