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US4375575A
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Dialkylbenzene isomerization process
Assignee: Shell USA Inc
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Filing: 1982-03-05
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Granted: 1983-03-01
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Expires: 2002-03-05
Abstract
Abstract Dialkylbenzene is isomerized by contact at 350° C.-600° C. with a novel siliceous composition prepared by impregnating porous silica with aluminum hydride and subsequently heating the impregnated silica to a temperature of from about 300° C. to about 900° C. in a non-oxidizing environment.
Inventors
- 👤 Lynn H. Slaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:45
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/02; C07D307/04; C07D307/06; C07D307/08; B; B01; B01J; B01J21/00; B01J21/12; C07C; C07C2/00; C07C2/02; C07C2/04; C07C2/06; C07C2/08; C07C2/26; C07C2/30; C07C2/54; C07C2/64; C07C2/66; C07C209/00; C07C209/04; C07C209/14; C07C209/18; C07C5/00; C07C5/22; C07C5/27; C07C5/2729; C07C5/2732; C07C5/2756; C07C5/2759; C07C6/00; C07C6/08; C07C6/12; C07C6/126; C07C2521/00; C07C2521/06; C07C2521/08; C07C2531/00; C07C2531/02; C07C2531/12; C07C2531/14; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
72 words
A process for isomerizing dialkylbenzenes which comprises contacting at about 350° to about 600° C. the dialkylbenzene with a catalyst prepared by a process which comprises impregnating a substantially dehydrated amorphorous silica gel with aluminum hydride dissolved in an anhydrous, non-hydroxyl containing organic solvent, drying the impregnated silica to remove the solvent and subsequently heating the impregnated silica at a temperature of about 300° to about 900° C. in a non-oxidizing atmosphere.
Claim 2
Dependent Claim
72 words
A process for isomerizing dialkylbenzenes which comprises contacting at about 350° to about 600° C. the dialkylbenzene with a catalyst prepared by a process which comprises impregnating a substantially dehydrated amorphorous silica gel with aluminum hydride dissolved in an anhydrous, non-hydroxyl containing organic solvent, drying the impregnated silica to remove the solvent and subsequently heating the impregnated silica at a temperature of about 300° to about 900° C. in a non-oxidizing atmosphere.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the impregnated silica is subsequently heated to a temperature of about 450° C. to about 750° C.
Claim 4
Dependent Claim
28 words
The process of claim 1 wherein the impregnated silica before heating contains from about 0.01 to about 35 percent by weight of aluminum hydride measured as aluminum metal.
Claim 5
Dependent Claim
28 words
The process of claim 1 wherein the impregnated silica before heating contains from about 0.1 to about 25 percent by weight of aluminum hydride measured as the metal.
Claim 6
Dependent Claim
28 words
The process of claim 1 wherein the impregnated silica before heating contains from about 1 to about 10 percent by weight of aluminum hydride measured as the metal.
Claim 7
Dependent Claim
25 words
The process of claim 5 wherein the aluminum hydride is AlH 3 .1/3(CH 3 CH 2 ) 2 O dissolved in tetrahydrofuran or diethyl ether.
Claim 8
Dependent Claim
28 words
The process of claim 2 wherein the impregnated silica before heating contains from about 0.01 to about 35 percent by weight of aluminum hydride measured as the metal.
Claim 9
Dependent Claim
28 words
The process of claim 2 wherein the impregnated silica before heating contains from about 0.1 to about 25 percent by weight of aluminum hydride measured as the metal.
Claim 10
Dependent Claim
28 words
The process of claim 2 wherein the impregnated silica before heating contains from about 1 to about 10 percent by weight of aluminum hydride measured as the metal.
Claim 11
Dependent Claim
25 words
The process of claim 9 wherein the aluminum hydride is AlH 3 .1/3(CH 3 CH 2 ) 2 O dissolved in tetrahydrofuran or diethyl ether.
Claim 12
Dependent Claim
17 words
The process of claim 1 wherein the temperature ranges from about 400° C. to about 550° C.
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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) | 1986-02-28 | 1986-08-30 | 1987-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-28 | 1990-08-30 | 1991-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-28 | 1994-08-30 | 1995-03-01 | $7700.00 | Window Closed / Lapsed |