Patent US4247726A successfully refreshed from Google Patents.
US4247726A
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Para-xylene process and catalyst
Assignee: Shell USA Inc
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Filing: 1980-02-21
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Granted: 1981-01-27
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Expires: 2000-02-21
Abstract
Abstract Isobutylene is selectively converted to para-xylene over a coupling catalyst consisting essentially of a neutral or weakly acidic support impregnated with a non-halogen containing water soluble rhenium compound and an alkali metal hydroxide or stannate and then reduced with hydrogen at elevated temperatures.
Inventors
- 👤 Lynn H. Slaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:45
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/76; C07C2521/00; C07C2521/02; C07C2521/04; C07C2521/06; C07C2521/08; C07C2523/00; C07C2523/02; C07C2523/04; C07C2523/14; C07C2523/16; C07C2523/32; C07C2523/36; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/52
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
51 words
A process for the selective conversion of isobuytlene to para-xylene which comprises reacting isobutylene over a coupling catalyst consisting essentially of a neutral or weakly acidic support impregnated with a non-halogen containing water soluble rhenium compound and an alkali metal hydroxide or stannate and then reduced with hydrogen at elevated temperatures.
Claim 2
Dependent Claim
51 words
A process for the selective conversion of isobuytlene to para-xylene which comprises reacting isobutylene over a coupling catalyst consisting essentially of a neutral or weakly acidic support impregnated with a non-halogen containing water soluble rhenium compound and an alkali metal hydroxide or stannate and then reduced with hydrogen at elevated temperatures.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein said catalyst is on a silica or alumina support.
Claim 4
Dependent Claim
22 words
The process of claim 2 wherein said alkali metal hydroxide or stannate is sodium hydroxide, sodium stannate, potassium hydroxide or potassium stannate.
Claim 5
Dependent Claim
17 words
The process of claim 3 wherein said reaction is conducted at temperatures between 450° and 550° C.
Claim 6
Dependent Claim
14 words
The process of claim 4 wherein said water soluble rhenium compound is ammonium perrhenate.
Claim 7
Dependent Claim
14 words
The process of claim 4 wherein said water soluble rhenium compound is rhenium heptaoxide.
Claim 8
Dependent Claim
15 words
The process of claim 5 wherein said alkali metal hydroxide or stannate is sodium hydroxide.
Claim 9
Dependent Claim
15 words
The process of claim 5 wherein said alkali metal hydroxide or stannate is sodium stannate.
Claim 10
Dependent Claim
15 words
The process of claim 6 wherein said alkali metal hydroxide or stannate is sodium hydroxide.
Claim 11
Dependent Claim
15 words
The process of claim 6 wherein said alkali metal hydroxide or stannate is sodium stannate.
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) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |