Patent US3792105A successfully refreshed from Google Patents.
US3792105A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of isoprene
Assignee: Shell USA Inc
•
Filing: 1972-10-11
•
Granted: 1974-02-12
•
Expires: 1992-10-11
Abstract
Abstract A PROCESS FOT THE REMOVAL OF ALLENES AND OTHER COMPOUNDS HINDERING THE POLYMERIZATION OF ISOPRENE FROM AN ISOPRENE-CONTAINING C5 HYDROCARBON FRACTION COMPRISES CONTACTING SAID FRACTION WITH FINELY DISPERSED METALLIC SODIUM AT A TEMPERATURE IN THE RANGE BETWEEN 58 AND 62*C.
Inventors
- 👤 R Siegmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:58
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/14833; C07C7/14841; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |