US3887630A
Expired / Lapsed
US
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Isomerization of alkyl aromatic hydrocarbons
Assignee: Union Oil Company of California
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Filing: 1974-02-04
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Granted: 1975-06-03
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Expires: 1994-02-04
Abstract
Abstract Alkyl aromatic hydrocarbons are isomerized using a unique stabilized hydrogen Y zeolite catalyst prepared by a sequence of (1) partial ammonium ion exchange of sodium Y zeolite, (2) steam calcination of the partially exchanged zeolite, preferably at relatively high temperatures, (3) further ammonium ion exchange to reduce the sodium content to a very low level, and (4) a second calcination at relatively low temperatures.
Inventors
- 👤 John W Ward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:48
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/22; C07C5/27; C07C5/2702; C07C5/2708; B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/08; B01J29/084; C07C5/2724
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
42 words
A PROCESS FOR THE ISOMERIZATION OF ALKYL AROMATIC HYDROCARBONS WHICH COMPRISES SUBJECTING SUCH HYDROCARBON, OR NON-EQUILIBRIUM MIXTURES THEREOF, TO ISOMERIZATION CONDITIONS IN CONTACT WITH A CATALYST COMPRISING AS ITS ESSENTIAL ACTIVE INGREDIENT A HYDROTHERMALLY STABLE Y ZEOLITE PREPARED BY THE STEPS OF:
Claim 2
Dependent Claim
42 words
A PROCESS FOR THE ISOMERIZATION OF ALKYL AROMATIC HYDROCARBONS WHICH COMPRISES SUBJECTING SUCH HYDROCARBON, OR NON-EQUILIBRIUM MIXTURES THEREOF, TO ISOMERIZATION CONDITIONS IN CONTACT WITH A CATALYST COMPRISING AS ITS ESSENTIAL ACTIVE INGREDIENT A HYDROTHERMALLY STABLE Y ZEOLITE PREPARED BY THE STEPS OF:
Claim 3
Dependent Claim
35 words
SUBJECTING AN AMMONIUM-SODIUM Y ZEOLITE CONTAINING BETWEEN ABOUT 1-5 WEIGHT-PERCENT NA2O TO CALCINATION IN THE PRESENCE OF STREAM AT TEMPERATURES ABOVE ABOUT 900*F BUT BELOW THE TEMPERATURE AT WHICH APPRECIABLE THERMAL DESTRUCTION OF CRYSTALLINITY OCCURS;
Claim 4
Dependent Claim
35 words
SUBJECTING AN AMMONIUM-SODIUM Y ZEOLITE CONTAINING BETWEEN ABOUT 1-5 WEIGHT-PERCENT NA2O TO CALCINATION IN THE PRESENCE OF STREAM AT TEMPERATURES ABOVE ABOUT 900*F BUT BELOW THE TEMPERATURE AT WHICH APPRECIABLE THERMAL DESTRUCTION OF CRYSTALLINITY OCCURS;
Claim 5
Dependent Claim
42 words
A process for the isomerization of alkyl aromatic hydrocarbons which comprises subjecting such hydrocarbon, or non-equilibrium mixtures thereof, to isomerization conditions in contact with a catalyst comprising as its essential active ingredient a hydrothermally stable Y zeolite prepared by the steps of:
Claim 6
Dependent Claim
42 words
A process for the isomerization of alkyl aromatic hydrocarbons which comprises subjecting such hydrocarbon, or non-equilibrium mixtures thereof, to isomerization conditions in contact with a catalyst comprising as its essential active ingredient a hydrothermally stable Y zeolite prepared by the steps of:
Claim 7
Dependent Claim
35 words
subjecting an ammonium-sodium Y zeolite containing between about 1-5 weight-percent Na2O to calcination in the presence of steam at temperatures above about 900*F but below the temperature at which appreciable thermal destruction of crystallinity occurs;
Claim 8
Dependent Claim
35 words
subjecting an ammonium-sodium Y zeolite containing between about 1-5 weight-percent Na2O to calcination in the presence of steam at temperatures above about 900*F but below the temperature at which appreciable thermal destruction of crystallinity occurs;
Claim 9
Dependent Claim
61 words
subjecting an ammonium-sodium Y zeolite containing between about 1.5 and 4 weight-percent sodium as Na2O to calcination at a temperature between about 1,100* and 1,500*F in contact with at least about one psi of water vapor pressure, and continuing said calcination for a time sufficient to reduce the unit cell size of said zeolite to between about 24.30 and 24.64 A;
Claim 10
Dependent Claim
61 words
subjecting an ammonium-sodium Y zeolite containing between about 1.5 and 4 weight-percent sodium as Na2O to calcination at a temperature between about 1,100* and 1,500*F in contact with at least about one psi of water vapor pressure, and continuing said calcination for a time sufficient to reduce the unit cell size of said zeolite to between about 24.30 and 24.64 A;
Claim 11
Dependent Claim
25 words
subjecting the resulting product to further ammonium ion exchange to replace at least about 50 percent of the zeolitic sodium ions with ammonium ions; and
Claim 12
Dependent Claim
25 words
subjecting the resulting product to further ammonium ion exchange to replace at least about 50 percent of the zeolitic sodium ions with ammonium ions; and
Claim 13
Dependent Claim
21 words
A process as defined in claim 1 wherein step (3) is carried out at a temperature between about 800* and 1,025*F.
Claim 14
Dependent Claim
25 words
subjecting the resulting product to further ammonium ion exchange to replace at least about 25 percent of the zeolitic sodium ions with ammonium ions; and
Claim 15
Dependent Claim
25 words
subjecting the resulting product to further ammonium ion exchange to replace at least about 25 percent of the zeolitic sodium ions with ammonium ions; and
Claim 16
Dependent Claim
25 words
SUBJECTING THE RESULTING PRODUCT TO FURTHER AMMONIUM ION EXCHANGE TO REPLACE AT LEAST ABOUT 25 PERCENT OF THE ZEOLITIC SODIUM IONS WITH AMMONIUM IONS; AND
Claim 17
Dependent Claim
25 words
SUBJECTING THE RESULTING PRODUCT TO FURTHER AMMONIUM ION EXCHANGE TO REPLACE AT LEAST ABOUT 25 PERCENT OF THE ZEOLITIC SODIUM IONS WITH AMMONIUM IONS; AND
Claim 18
Dependent Claim
22 words
CALCINING THE RESULTING PRODUCT AT A TEMPERATURE BETWEEN ABOUT 700* AND 1,200*F FOR A TIME SUFFICIENT TO EFFECT DEAMMONIATION WITHOUT SUBSTANTIAL DEHYDROXYLATION.
Claim 19
Dependent Claim
22 words
CALCINING THE RESULTING PRODUCT AT A TEMPERATURE BETWEEN ABOUT 700* AND 1,200*F FOR A TIME SUFFICIENT TO EFFECT DEAMMONIATION WITHOUT SUBSTANTIAL DEHYDROXYLATION.
Claim 20
Dependent Claim
22 words
calcining the resulting product at a temperature between about 700* and 1,200*F for a time sufficient to effect deammoniation without substantial dehydroxylation.
Claim 21
Dependent Claim
22 words
calcining the resulting product at a temperature between about 700* and 1,200*F for a time sufficient to effect deammoniation without substantial dehydroxylation.
Claim 22
Dependent Claim
32 words
calcining the exchanged product from step (2) at a temperature between about 700* and 1,200*F for a time sufficient to effect deammoniation without substantial dehydroxylation or further shrinkage in unit cell size.
Claim 23
Dependent Claim
32 words
calcining the exchanged product from step (2) at a temperature between about 700* and 1,200*F for a time sufficient to effect deammoniation without substantial dehydroxylation or further shrinkage in unit cell size.
Claim 24
Dependent Claim
18 words
A process as defined in claim 1 wherein said alkyl aromatic hydrocarbon comprises at least one xylene isomer.
Claim 25
Dependent Claim
21 words
A process as defined in claim 3 wherein step (3) is carried out at a temperature between about 800* and 1,025*F.
Claim 26
Dependent Claim
34 words
A process as defined in claim 1 wherein said contacting is carried out in the presence of added hydrogen, and said catalyst contains a catalytically effective proportion of at least one Group VIII metal.
Claim 27
Dependent Claim
42 words
A process for the isomerization of alkyl aromatic hydrocarbons which comprises subjecting such hydrocarbon, or non-equilibrium mixtures thereof, to isomerization conditions in contact with a catalyst comprising as its essential active ingredient a hydrothermally stable Y zeolite prepared by the steps of:
Claim 28
Dependent Claim
42 words
A process for the isomerization of alkyl aromatic hydrocarbons which comprises subjecting such hydrocarbon, or non-equilibrium mixtures thereof, to isomerization conditions in contact with a catalyst comprising as its essential active ingredient a hydrothermally stable Y zeolite prepared by the steps of:
Claim 29
Dependent Claim
21 words
A process as defined in claim 6 wherein step (3) is carried out at a temperature between about 800* and 1,025*F.
Claim 30
Dependent Claim
18 words
A process as defined in claim 6 wherein said alkyl aromatic hydrocarbon comprises at least one xylene isomer.
Claim 31
Dependent Claim
21 words
A process as defined in claim 8 wherein step (3) is carried out at a temperature between about 800* and 1,025*F.
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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |