Patent US4046824A successfully refreshed from Google Patents.
US4046824A
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Process for selective hydrogenation of ethylbenzene
Assignee: Chevron USA Inc
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Filing: 1975-12-31
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Granted: 1977-09-06
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Expires: 1995-12-31
Abstract
Abstract An improved process for selective hydrogenation of ethylbenzene which employs a rhodium catalyst and mild reaction conditions, and is especially useful to reduce the concentration of ethylbenzene in mixtures comprising ethylbenzene and at least one xylene isomer.
Inventors
- 👤 Derek L. Ransley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:15
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/02; C07C5/10; C07C7/00; C07C7/148; C07C7/163; C07C2521/00; C07C2521/02; C07C2521/04; C07C2523/00; C07C2523/38; C07C2523/40; C07C2523/46; C07C2601/00; C07C2601/12
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
49 words
A process for selectively hydrogenating ethylbenzene in a C 8 aromatic mixture comprising ethylbenzene and at least one xylene isomer, which comprises heating said mixture with hydrogen in the presence of a catalyst consisting essentially of rhodium until from about 5% to about 60% of said mixture is hydrogenated.
Claim 2
Dependent Claim
49 words
A process for selectively hydrogenating ethylbenzene in a C 8 aromatic mixture comprising ethylbenzene and at least one xylene isomer, which comprises heating said mixture with hydrogen in the presence of a catalyst consisting essentially of rhodium until from about 5% to about 60% of said mixture is hydrogenated.
Claim 3
Dependent Claim
27 words
A process according to claim 1 wherein said heating is carried out at a temperature in the range of from about 20° C. to about 90° C.
Claim 4
Dependent Claim
25 words
A process according to claim 2 wherein said heating is carried out at a hydrogen pressure of from about 0.5 atmospheres to about 15 atmospheres.
Claim 5
Dependent Claim
22 words
A process according to claim 1 wherein said C 8 aromatic mixture comprises approximately equal amounts of ethylbenzene, p-xylene, o-xylene, and meta-xylene.
Claim 6
Dependent Claim
15 words
A process according to claim 1 wherein said rhodium catalyst is supported on an alumina.
Claim 7
Dependent Claim
23 words
A process according to claim 1 wherein said process is carried out at an aromatic conversion of from about 10% to about 30%.
Claim 8
Dependent Claim
23 words
A process according to claim 1 wherein said process is carried out at an aromatic conversion of from about 5% to about 10%.
Claim 9
Dependent Claim
59 words
An improved process for preparing a ethylbenzene reduced C 8 aromatic mixture which comprises heating a C 8 aromatic feed mixture comprising ethylbenzene and at least one xylene isomer with hydrogen in the presence of a rhodium catalyst until from about 5% to about 60% of the feed mixture is hydrogenated, and separating the hydrogenated non-aromatic fraction comprising ethylcyclohexane.
Claim 10
Dependent Claim
59 words
An improved process for preparing a ethylbenzene reduced C 8 aromatic mixture which comprises heating a C 8 aromatic feed mixture comprising ethylbenzene and at least one xylene isomer with hydrogen in the presence of a rhodium catalyst until from about 5% to about 60% of the feed mixture is hydrogenated, and separating the hydrogenated non-aromatic fraction comprising ethylcyclohexane.
Claim 11
Dependent Claim
21 words
A process according to claim 8 wherein said conditions include a temperature of from about 20° C. to about 90° C.
Claim 12
Dependent Claim
14 words
A process according to claim 8 wherein said rhodium catalyst is supported on alumina.
Claim 13
Dependent Claim
23 words
A process according to claim 8 wherein said process is carried out at a aromatic conversion of from about 10% to about 30%.
Claim 14
Dependent Claim
13 words
A process according to claim 8 wherein said separation is effected by distillation.
Claim 15
Dependent Claim
24 words
A process according to claim 1 wherein said heating is carried out at a temperature of from about 30° C. to about 60° C.
Claim 16
Dependent Claim
55 words
A process according to claim 1 wherein said process is carried out in the fluid phase at a temperature of about 40° C., a hydrogen pressure of about 5 atmospheres, a hydrogen-to-hydrocarbon ratio of about 10:1, and a liquid hourly space velocity of hydrocarbon charge of about 3.0 volumes per volume of catalyst per hour.
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) | 1980-09-05 | 1981-03-07 | 1981-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-05 | 1985-03-07 | 1985-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-05 | 1989-03-07 | 1989-09-06 | $7700.00 | Window Closed / Lapsed |