Patent US2508922A successfully refreshed from Google Patents.
US2508922A
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Separation of dienes
Assignee: Shell Development Co
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Filing: 1948-05-17
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Granted: 1950-05-23
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Expires: 1968-05-17
Abstract
No abstract record available.
Inventors
- 👤 Jr Daniel B Luten
- 👤 Kenneth W Hedberg
- 👤 Benedictis Aldo De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:10
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/005; C07C7/148; C07C7/177; C10; C10G; C10G50/00; C10G53/00; C10G53/02; C10G7/00; C07C2601/00; C07C2601/06; C07C2601/10; Y; Y10; Y10S; Y10S585/00; Y10S585/929; Y10S585/94; Y10S585/947
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
137 words
A PROCESS FOR THE SEPARATION OF ISOPRENE AND CYLCOPENTADIENE FROM A HYDROCARBON MIXTURE CONTAINING THE SAID ISOPRENE AND CYCLOPENTADIENE WHICH COMPRISES DIMERIZING THE SAID MIXTURE TO CONVERT THE CYCLOPENTADIENE TO DICYCLOPENTADIENE, SEPARATING OUT A MONOMERIC FRACTION COMPRISING ISOPRENE AND A DIMERIZED FRACTION, HEATING THE DIMERIZED FRACTION AT A TEMPERATURE OF BETWEEN ABOUT 150*C. TO ABOUT 450* C. FOR A SHORT TIME TO CONVERT THE DICYCLOPENTADIENE TO CYCLOPENTADIENE, SEPARATING OUT OF THE PYROLYZED MIXTURE (1) CYCLOPENTADIENE, AND (2) THE UNAFFECTED DIMER, HEATING THE UNAFFECTED DIMER FRACTION AT A TEMPERATURE ABOVE ABOUT 500*C. WHEREBY THE LIMONENE AND CO-DIMERS OF ISOPRENE AND CYCLOPENTADIENE FORMED IN THE INITIAL DIMERIZATION STEP ARE CONVERTED TO MONOMERIC ISOPRENE AND CYCLOPENTADIENE, SEPARATING OUT A FRACTION COMPRISING THE MONOMERIC ISOPRENE AND CYCLOPENTADIENE FROM THE PYROLYZED MIXTURE AND RECYCLING THE SAID FRACTION TO THE INITIAL DIMERIZATION STEP.
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) | 1953-05-22 | 1953-11-21 | 1954-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-05-22 | 1957-11-21 | 1958-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-05-22 | 1961-11-21 | 1962-05-23 | $7700.00 | Window Closed / Lapsed |