US4843181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of 1,1,1-trifluorodichloroethane and 1,1,1,2-tetrafluorochloroethane
Assignee: EIDP Inc
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Filing: 1987-10-22
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Granted: 1989-06-27
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Expires: 2007-10-22
Abstract
Abstract An improved gas-phase process for the manufacture of 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane by contacting a suitable tetrahaloethylene and/or pentahaloethane with hydrogen fluoride in the presence of Cr 2 O 3 , prepared by pyrolysis of (NH 4 ) 2 Cr 2 O 7 , the reaction being conducted under controlled conditions whereby the production of pentafluoroethane is minimized.
Inventors
- 👤 William H. Gumprecht
- 👤 Leo E. Manzer
- 👤 V. N. Mallikarjuna Rao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:49
CPC Classifications
C; C07; C07C; C07C19/00; C07C17/00; C07C17/07; C07C17/087; C07C17/093; C07C17/20; C07C17/21
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
122 words
A process for the preparation of 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane by fluorination of a tetrahaloethylene, C 2 Cl 4-x F x , wherein x=0 to 3, and/or pentahaloethane, C 2 HCl 5-x F x , wherein x=0 to 2, comprising contacting in the gaseous phase at effective temperature, mol ratio and contact time, said tetrahaloethylene and/or pentahaloethane with HF and Cr 2 O 3 , said Cr 2 O 3 prepared by pyrolysis of (NH 4 ) 2 Cr 2 O 7 , said contacting producing a product stream containing 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane and pentafluoroethane, wherein the amount of said 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane produced is greater than the amount of pentafluoroethane produced and, thereafter, separating the 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane from the product stream.
Claim 2
Dependent Claim
122 words
A process for the preparation of 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane by fluorination of a tetrahaloethylene, C 2 Cl 4-x F x , wherein x=0 to 3, and/or pentahaloethane, C 2 HCl 5-x F x , wherein x=0 to 2, comprising contacting in the gaseous phase at effective temperature, mol ratio and contact time, said tetrahaloethylene and/or pentahaloethane with HF and Cr 2 O 3 , said Cr 2 O 3 prepared by pyrolysis of (NH 4 ) 2 Cr 2 O 7 , said contacting producing a product stream containing 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane and pentafluoroethane, wherein the amount of said 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane produced is greater than the amount of pentafluoroethane produced and, thereafter, separating the 1,1,1-trifluorodichloroethane and/or 1,1,1,2-tetrafluorochloroethane from the product stream.
Claim 3
Dependent Claim
10 words
The process of claim 1 wherein the tetrahaloethylene is tetrachloroethylene.
Claim 4
Dependent Claim
48 words
The process of claim 1 wherein the HF is contacted with the tetrahaloethylene and/or pentahaloethane at a mol ratio of about 1/1 to about 20/1, at a temperature of about 225° C. to about 400° C., and a contact time of about 0.1 seconds to about 100 seconds.
Claim 5
Dependent Claim
48 words
The process of claim 3 wherein the HF is contacted with the tetrahaloethylene and/or pentahaloethane at a mol ratio of about 3/1 to about 10/1, at a temperature of about 225° C. to about 250° C., and a contact time of about 10 seconds to about 90 seconds.
Claim 6
Dependent Claim
48 words
The process of claim 4 wherein the HF is contacted with the tetrahaloethylene and/or pentahaloethane at a mol ratio of about 4/1 to about 6/1, at a temperature of about 225° C. to about 250° C., and a contact time of about 15 seconds to about 90 seconds.
Claim 7
Dependent Claim
21 words
The process of claim 1 wherein conversion of the tetrahaloethylene and/or pentahaloethane to fluorinated products is between about 30% and 100%.
Claim 8
Dependent Claim
23 words
The process of claim 1 wherein the amount of pentafluoroethane in the product stream is less than 10 area percent by gas chromatography.
Claim 9
Dependent Claim
21 words
The process of claim 1 further comprising the step of recycling at least a portion of starting materials and underfluorinated products.
Claim 10
Dependent Claim
17 words
The process of claim 1 wherein the Cr 2 O 3 contains 100 ppm potassium or less.
Claim 11
Dependent Claim
26 words
The process of claim 1 wherein before the contacting step, the Cr 2 O 3 is given a pretreatment by passing hydrogen fluoride gas over it.
Claim 12
Dependent Claim
26 words
The process of claim 10 wherein the pretreatment is carried out for about 15 to about 300 minutes at about 200° C. to about 450° 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) | 1992-06-26 | 1992-12-26 | 1993-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-26 | 1996-12-26 | 1997-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-26 | 2000-12-26 | 2001-06-27 | $7700.00 | Window Closed / Lapsed |