US4229320A
Expired / Lapsed
US
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Catalyst for making para-xylene
Assignee: Shell USA Inc
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Filing: 1979-01-22
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Granted: 1980-10-21
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Expires: 1999-01-22
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
2026-11-08 01:38
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/16; B01J23/32; B01J23/36; 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: 7
Claim 1
Independent Claim
90 words
A catalytic composition which is prepared by a process which consists essentially of impregnating a neutral or weakly acidic support with an aqueous solution of a non-halogen containing water soluble rhenium compound before or after impregnating the support with an alkali metal hydroxide or stannate, with the proviso that the support is calcined after impregnation with said rhenium compound, and then reducing the impregnated support with hydrogen at elevated temperatures sufficient to reduce the rhenium component to its metallic state while leaving the alkali metal hydroxide or stannate largely unreduced.
Claim 2
Dependent Claim
90 words
A catalytic composition which is prepared by a process which consists essentially of impregnating a neutral or weakly acidic support with an aqueous solution of a non-halogen containing water soluble rhenium compound before or after impregnating the support with an alkali metal hydroxide or stannate, with the proviso that the support is calcined after impregnation with said rhenium compound, and then reducing the impregnated support with hydrogen at elevated temperatures sufficient to reduce the rhenium component to its metallic state while leaving the alkali metal hydroxide or stannate largely unreduced.
Claim 3
Dependent Claim
16 words
The catalytic composition of claim 1 wherein said catalyst is on a silica or alumina support.
Claim 4
Dependent Claim
23 words
The catalytic composition of claim 2 wherein said alkali metal hydroxide or stannate is sodium hydroxide, sodium stannate, potassium hydroxide or potassium stannate.
Claim 5
Dependent Claim
18 words
The catalytic composition of claim 3 wherein said water soluble rhenium compound is ammonium perrhenate or rhenium heptaoxide.
Claim 6
Dependent Claim
17 words
The catalytic composition of claim 4 wherein said alkali metal hydroxide is sodium hydroxide or sodium stannate.
Claim 7
Dependent Claim
26 words
The catalytic composition of claim 11 wherein the support is impregnated with said rhenium compound, calcined and then impregnated with said alkali metal hydroxide or 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) | 1983-10-21 | 1984-04-21 | 1984-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-21 | 1988-04-21 | 1988-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-21 | 1992-04-21 | 1992-10-21 | $7700.00 | Window Closed / Lapsed |