US4902838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Isomerization of saturated fluorohydrocarbons
Assignee: EIDP Inc
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Filing: 1988-12-28
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Granted: 1990-02-20
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Expires: 2008-12-28
Abstract
Abstract A process for isomerizing saturated C 2 to C 6 fluorohydrocarbons having lesser thermodynamic stability to fluorohydrocarbons having greater thermodynamic stability comprising contacting in the gaseous phase at a temperature from about 200° C. to about 475° C. at least one C 2 to C 6 saturated fluorohydrocarbon with a catalyst composition comprising an aluminum fluoride.
Inventors
- 👤 Leo E. Manzer
- 👤 V. N. Mallikarjuna Rao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:49
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/35; C07C17/358
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
56 words
A process for isomerizing saturated C 2 to C 6 fluorohydrocarbons having lesser thermodynamic stability to fluorohydrocarbons having greater thermodynamic stability comprising; contacting in the gaseous phase at a temperature from about 200° C. to about 475° C. at least one C 2 to C 6 saturated fluorohydrocarbon with a catalyst composition comprising an aluminum fluoride.
Claim 2
Dependent Claim
56 words
A process for isomerizing saturated C 2 to C 6 fluorohydrocarbons having lesser thermodynamic stability to fluorohydrocarbons having greater thermodynamic stability comprising; contacting in the gaseous phase at a temperature from about 200° C. to about 475° C. at least one C 2 to C 6 saturated fluorohydrocarbon with a catalyst composition comprising an aluminum fluoride.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein the saturated fluorohydrocarbon having lesser thermodynamic stability is selected from at least one of 1,1,2,2-tetrafluoroethane, 1,1,2-trifluoroethane and 1,2-difluoroethane.
Claim 4
Dependent Claim
15 words
The process of claim 2 wherein the saturated fluorohydrocarbon having lesser thermodynamic stability is 1,1,2,2-tetrafluoroethane.
Claim 5
Dependent Claim
27 words
The process of claim 1 wherein the isomer of the saturated fluorohydrocarbon having greater thermodynamic stability is selected from at least one of 1,1,1,2-tetrafluoroethane, 1,1,1-trifluoroethane and 1,1-difluoroethane.
Claim 6
Dependent Claim
18 words
The process of claim 4 wherein the isomer of the saturated fluorohydrocarbon having greater thermodynamic stability is 1,1,1,2-tetrafluoroethane.
Claim 7
Dependent Claim
21 words
The process of claim 1 wherein the aluminum fluoride is selected from at least one of AlF 3 and fluorided alumina.
Claim 8
Dependent Claim
41 words
The process of claim 6 wherein the fluorided alumina is a high fluorine-content composition comprising aluminum, oxygen, and fluorine in such proportions that the total fluorine content of the catalyst composition taken as AlF 3 is at least 50 weight percent.
Claim 9
Dependent Claim
61 words
The process of claim 1 wherein the catalyst composition comprises up to 50% by weight of at least one metal on a support consisting essentially of aluminum, oxygen, and fluorine in such proportions that the fluorine content of the catalyst composition corresponds to an AlF 3 content of at least 50% by weight of the catalyst composition exclusive of the metal.
Claim 10
Dependent Claim
17 words
The process of claim 1 wherein the temperature is from about 300° C. to about 450° C.
Claim 11
Dependent Claim
17 words
The process of claim 1 wherein the temperature is from about 350° C. to about 450° C.
Claim 12
Dependent Claim
52 words
The process of claim 1 wherein the catalyst composition is treated with a vaporizable fluorine-containing fluorinating compound at a temperature from about 200° C. to about 450° C. until the fluorine content of the catalyst composition corresponds to an AlF 3 content of at least 50% by weight of the catalyst composition.
Claim 13
Dependent Claim
17 words
The process of claim 1 wherein the contacting is conducted in the presence of an oxygen-containing gas.
References Cited (Backward Citations)
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US3398202A
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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) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |