US2632779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of paraxylene
Assignee: Standard Oil Development Co
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Filing: 1950-05-29
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Granted: 1953-03-24
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Expires: 1970-05-29
Abstract
No abstract record available.
Inventors
- 👤 Reuben F Pfennig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:24
CPC Classifications
C; C07; C07C; C07C15/00; C07C15/02; C07C15/067; C07C15/08; C07C5/00; C07C5/22; C07C5/27; C07C5/2729; C07C5/2732; C07C5/2735
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
199 words
A METHOD FOR PRODUCING PARAXYLENE FROM A FEED STOCK FRACTION CONSISTING OF C8 AROMATIC HYDROCARBONS CONTAINING METAXYLENE FROM WHICH AS MUCH PARAXYLENE HAS BEEN REMOVED AS CAN BE SEPARATED BY CHILLING TO A LOW TEMPERATURE TO CRYSTALLIZE THE PARAXYLENE AS CRYSTALS AND SEPARATING THE PARAXYLENE CRYSTALS THEREFROM WHICH COMPRISES CONTACTING SAID FEED STOCK FRACTION WITH A CATALYST SELECTED FROM THE OXIDES AND SULFIDES OF THE METALS FROM GROUP VI OF THE PERIODIC TABLE AT A TEMPERATURE IN THE RANGE BETWEEN 800* AND 1150* F. IN THE PRESENCE OF 50 TO 2500 CUBIC FEET OF HYDROGEN PER BARRAL OF SAID FEED MIXTURE AND A PRESSURE IN THE RANGE OF 50 TO 500 P.S.I.G. AND AT A SPACE VELOCITY OF 1 TO 5 VOLUMES OF FEED PER VOLUME OF CATALYST PER HOUR TO FORM A PRODUCT COMPRISING SUBSTANTIAL QUANTITIES OF PARAXYLENE, REMOVING FROM SAID PRODUCT FRACTIONS BOILING BELOW AND ABOVE THE BOILING POINT OF SAID FEED MIXTURE, CHILLING SAID PRODUCT FROM WHICH FRACTIONS BOILING BELOW AND ABOVE THE SAID FEED MIXTURE HAVE BEEN REMOVED TO A TEMPERATURE SUFFICIENTLY LOW TO FORM A SLURRY OF PARAXYLENE CRYSTALS, SEPARATING SAID SLURRY INTO A FILTER CAKE OF PARAXYLENE CRYSTALS AND A MOTHER LIQUOR AND
Claim 2
Independent Claim
199 words
A METHOD FOR PRODUCING PARAXYLENE FROM A FEED STOCK FRACTION CONSISTING OF C8 AROMATIC HYDROCARBONS CONTAINING METAXYLENE FROM WHICH AS MUCH PARAXYLENE HAS BEEN REMOVED AS CAN BE SEPARATED BY CHILLING TO A LOW TEMPERATURE TO CRYSTALLIZE THE PARAXYLENE AS CRYSTALS AND SEPARATING THE PARAXYLENE CRYSTALS THEREFROM WHICH COMPRISES CONTACTING SAID FEED STOCK FRACTION WITH A CATALYST SELECTED FROM THE OXIDES AND SULFIDES OF THE METALS FROM GROUP VI OF THE PERIODIC TABLE AT A TEMPERATURE IN THE RANGE BETWEEN 800* AND 1150* F. IN THE PRESENCE OF 50 TO 2500 CUBIC FEET OF HYDROGEN PER BARRAL OF SAID FEED MIXTURE AND A PRESSURE IN THE RANGE OF 50 TO 500 P.S.I.G. AND AT A SPACE VELOCITY OF 1 TO 5 VOLUMES OF FEED PER VOLUME OF CATALYST PER HOUR TO FORM A PRODUCT COMPRISING SUBSTANTIAL QUANTITIES OF PARAXYLENE, REMOVING FROM SAID PRODUCT FRACTIONS BOILING BELOW AND ABOVE THE BOILING POINT OF SAID FEED MIXTURE, CHILLING SAID PRODUCT FROM WHICH FRACTIONS BOILING BELOW AND ABOVE THE SAID FEED MIXTURE HAVE BEEN REMOVED TO A TEMPERATURE SUFFICIENTLY LOW TO FORM A SLURRY OF PARAXYLENE CRYSTALS, SEPARATING SAID SLURRY INTO A FILTER CAKE OF PARAXYLENE CRYSTALS AND A MOTHER LIQUOR AND
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) | 1956-03-23 | 1956-09-22 | 1957-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-03-23 | 1960-09-22 | 1961-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-03-23 | 1964-09-22 | 1965-03-24 | $7700.00 | Window Closed / Lapsed |