US3856873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Xylene isomerization
Assignee: Mobil Oil AS
•
Filing: 1973-09-13
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Granted: 1974-12-24
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Expires: 1993-09-13
Abstract
Abstract Mixtures of C8 aromatic hydrocarbons are contacted in vapor phase with acid zeolite ZSM-5. The xylene content is thereby isomerized and the ethyl benzene content of the charge is converted in a manner which results in net increase of aromatic rings.
Inventors
- 👤 G Burress
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:57
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/22; C07C5/27; C07C5/2729; C07C5/2732; C07C5/2737; C07C5/2767; C07C5/277; C07C5/2775
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
IN A PROCESS FOR CONVERSION OF A MIXTURE OF AROMATIC COMPOUNDS HAVING EIGHT CARBON ATOMS SAID MIXTURE CONTAINING ETHYL BENZENE AND XYLENES, TO ISOMERIZE XYLENES CONTAINED IN SAID MIXTURE AND CONVERT AT LEAST PART OF ETHYL BENZENE SO CONTAINED TO XYLENE OR TO COMPOUNDS READILY SEPARABLY BY DISTILLATION FROM EIGHT CARBON ATOMS AROMATICS; THE IMPROVEMENT WHICH COMPRISES CONTACTING SUCH MIXTURE OF EIGHT CARBON ATOM AROMATIC COMPOUNDS WITH A CATALYST WHICH COMPRISES ACID ZEOLITE OF THE ZSM-5 TYPE, ACID ZEOLITE ZSM-12 OR ACID ZEOLITE ZSM2-21 IN VAPOR PHASE AND IN THE ABSENCE OF ADDED HYDROGEN AT A TEMPERATURE OF ABOUT 500*F. TO ABOUT 1,000*F.
Claim 2
Dependent Claim
103 words
IN A PROCESS FOR CONVERSION OF A MIXTURE OF AROMATIC COMPOUNDS HAVING EIGHT CARBON ATOMS SAID MIXTURE CONTAINING ETHYL BENZENE AND XYLENES, TO ISOMERIZE XYLENES CONTAINED IN SAID MIXTURE AND CONVERT AT LEAST PART OF ETHYL BENZENE SO CONTAINED TO XYLENE OR TO COMPOUNDS READILY SEPARABLY BY DISTILLATION FROM EIGHT CARBON ATOMS AROMATICS; THE IMPROVEMENT WHICH COMPRISES CONTACTING SUCH MIXTURE OF EIGHT CARBON ATOM AROMATIC COMPOUNDS WITH A CATALYST WHICH COMPRISES ACID ZEOLITE OF THE ZSM-5 TYPE, ACID ZEOLITE ZSM-12 OR ACID ZEOLITE ZSM2-21 IN VAPOR PHASE AND IN THE ABSENCE OF ADDED HYDROGEN AT A TEMPERATURE OF ABOUT 500*F. TO ABOUT 1,000*F.
References Cited (Backward Citations)
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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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |