US3887439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of fluorinated dimethyl ethers by extractive distillation
Assignee: Phillips Petroleum Co
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Filing: 1972-09-25
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Granted: 1975-06-03
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Expires: 1992-09-25
Abstract
Abstract A process for the extractive distillation of fluorinated dimethyl ether, dimethyl ether and anhydrous hydrogen fluoride (HF) is described. Trifluoromethyl difluoromethyl ether (F5) can be separated from dimethyl ether (Fo) by extractive distillation in the presence of anhydrous hydrogen fluoride (HF) as a selective solvent with the recovery of trifluoromethyl difluoromethyl ether (F5) in a first effluent product stream and the recovery of dimethyl ether (Fo) and anhydrous hydrogen fluoride (HF) in a second effluent product stream. Bisdifluoromethyl ether (F4) and/or monofluoromethyl difluoromethyl ether (F3) can be separated from dimethyl ether and anhydrous hydrogen fluoride (HF) by extractive distillation in the presence of dimethyl ether (Fo) as a selective solvent with the recovery of bis-difluoromethyl ether (F4) and/or monofluoromethyl difluoromethyl ether (F3) and the recovery of anhydrous hydrogen fluoride (HF) and dimethyl ether (Fo) in a second effluent product stream. The use of anhydrous hydrogen fluoride (HF) and dimethyl ether (Fo) as the extractive solvents and the separation of the components of an electrochemical fluorination reaction is advantageous in that the anhydrous hydrogen fluoride (HF) and dimethyl ether (Fo) effluent stream can be recycled to the electrochemical fluorination reactions.
Inventors
- 👤 William M Hutchinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:27
CPC Classifications
C; C07; C07C; C07C43/00; C07C43/02; C07C43/03; C07C43/04; C07C43/12; C07C43/123
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
85 words
An extractive distillation process comprising: passing a first feedstock stream comprising trifluoromethyl difluoromethyl ether (F5) and dimethyl ether (F0) into a first extractive distillAtion zone; passing a first selective solvent stream comprising anhydrous hydrogen fluoride (HF) into said first extractive distillation zone; separating and withdrawing from said first extractive distillation zone a first overhead effluent stream comprising trifluoromethyl difluoromethyl ether (F5); and separating and withdrawing from said first extractive distillation zone a first bottoms effluent stream comprising dimethyl ether (F0) and anhydrous hydrogen fluoride (HF).
Claim 2
Dependent Claim
85 words
An extractive distillation process comprising: passing a first feedstock stream comprising trifluoromethyl difluoromethyl ether (F5) and dimethyl ether (F0) into a first extractive distillAtion zone; passing a first selective solvent stream comprising anhydrous hydrogen fluoride (HF) into said first extractive distillation zone; separating and withdrawing from said first extractive distillation zone a first overhead effluent stream comprising trifluoromethyl difluoromethyl ether (F5); and separating and withdrawing from said first extractive distillation zone a first bottoms effluent stream comprising dimethyl ether (F0) and anhydrous hydrogen fluoride (HF).
Claim 3
Dependent Claim
85 words
AN EXTRACTIVE DISTILLATION PROCESS COMPRISING: PASSING A FIRST FEEDSTOCK STREAM COMPRISING TRIFLUOROMETHYL DIFLUOROMETHYL ETHER (F5) AND DIMETHYL ETHER (F0) INTO A FIRST EXTRACTIVE DISTILLATION ZONE, PASSING A FIRST SELECTIVE SOLVENT STREAM COMPRISING ANHYDROUS HYDROGEN FLUORIDE (HF) INTO SAID FIRST EXTRACTIVE DISTILLATION ZONE, SEPARATING AND WITHDRAWING FROM SAID FIRST EXTRACTIVE DISTILLATION ZONE A FIRST OVERHEAD EFFLUENT STREAM COMPRISING TRIFLUOROMETHYL DIFLUOROMETHYL ETHER (F5), AND SEPARATING AND WITHDRAWING FROM SAID FIRST EXTRACTIVE DISTILLATION ZONE A FIRST BOTTOMS EFFLUENT STREAM COMPRISING DIMETHYL ETHER (F0) AND ANHYDROUS HYDROGEN FLUORIDE (HF).
Claim 4
Dependent Claim
85 words
AN EXTRACTIVE DISTILLATION PROCESS COMPRISING: PASSING A FIRST FEEDSTOCK STREAM COMPRISING TRIFLUOROMETHYL DIFLUOROMETHYL ETHER (F5) AND DIMETHYL ETHER (F0) INTO A FIRST EXTRACTIVE DISTILLATION ZONE, PASSING A FIRST SELECTIVE SOLVENT STREAM COMPRISING ANHYDROUS HYDROGEN FLUORIDE (HF) INTO SAID FIRST EXTRACTIVE DISTILLATION ZONE, SEPARATING AND WITHDRAWING FROM SAID FIRST EXTRACTIVE DISTILLATION ZONE A FIRST OVERHEAD EFFLUENT STREAM COMPRISING TRIFLUOROMETHYL DIFLUOROMETHYL ETHER (F5), AND SEPARATING AND WITHDRAWING FROM SAID FIRST EXTRACTIVE DISTILLATION ZONE A FIRST BOTTOMS EFFLUENT STREAM COMPRISING DIMETHYL ETHER (F0) AND ANHYDROUS HYDROGEN FLUORIDE (HF).
Claim 5
Dependent Claim
22 words
A process in accordance with claim 1 wherein said first overhead effluent stream is at least substantially free of dimethyl ether (F0).
Claim 6
Dependent Claim
41 words
A process in accordance with claim 1 wherein dimethyl ether (F0) and anhydrous hydrogen fluoride (HF) are present within said first extractive distillation zone in a ratio by weight of F0:HF within the range of from about 1:10 to about 10:1.
Claim 7
Dependent Claim
60 words
A process in accordance with claim 3 wherein said ratio by weight of F0:HF is within the range of from about 1:3 to about 3: 1, wherein the temperatures within said first extractive distillation zone are within the range of from about -35*C. to about +35*C., and wherein the pressure within said first extractive distillation zone is about atmospheric pressure.
Claim 8
Dependent Claim
25 words
A process in accordance with claim 4 wherein said ratio by weight of F0:HF is within the range of from about 1:1.5 to about 1.5:1.
Claim 9
Dependent Claim
120 words
A process in accordance with claim 1 wherein each of said first feedstock stream and said first bottoms effluent stream additionally comprises at least one additional component selected from the group consisting of bisdifluoromethyl ether (F4) and monofluoromethyl difluoromethyl ether (F3), and wherein said process additionally comprises: passing said first bottoms effluent stream into a second extractive distillation zone; passing a second selective solvent stream comprising dimethyl ether (F0) into said second extractive distillation zone; separating and withdrawing from said second extractive distillation zone a second overhead effluent stream comprising said at least one additional component; and separating and withdrawing from said second extractive distillation zone a second bottoms effluent stream comprising dimethyl ether (F0) and anhydrous hydrogen fluoride (HF).
Claim 10
Dependent Claim
43 words
A process in accordance with claim 6 wherein said first overhead effluent stream is at least substantially free of dimethyl ether (F0), and wherein said second overhead effluent stream is at least substantially free of anhydrous hydrogen fluoride (HF) and dimethyl ether (F0).
Claim 11
Dependent Claim
76 words
A process in accordance with claim 6 wherein dimethyl ether (F0) and anhydrous hydrogen fluoride (HF) are present within said first extractive distillation zone in a ratio by weight of F0:HF within the range of from about 1:10 to about 10:1, and wherein dimethyl ether (F0) and anhydrous hydrogen fluoride (HF) are present within said second extractive distillation zone in a ratio by weight of F0:HF within the range of from about 1:10 to about 10:1.
Claim 12
Dependent Claim
122 words
A process in accordance with claim 8 wherein said ratio by weight of F0:HF within said first extractive distillation zone is within the range of from about 1:3 to about 3:1, wherein the temperatures within said first extractive distillation zone are within the range of from about -35*C. to about +35*C., wherein the pressure within said first extractive distillation zone is about atmospheric pressure, wherein said ratio by weight of F0:HF within said second extractive distillation zone is within the range of from about 1:3 to about 3:1, wherein the temperatures within said second extractive distillation zone are within the range of from about 10*C. to about 70*C., and wherein the pressure within said second extractive distillation zone is about atmospheric pressure.
Claim 13
Dependent Claim
56 words
A process in accordance with claim 9 wherein said ratio by weight of F0:HF within said first extractive distillation zone is within the range of from about 1:1.5 to about 1.5:1, and wherein said ratio by weight of F0:HF within said second extractive distillation zone is within the range of from about 1:1.5 to about 1.5:1.
Claim 14
Dependent Claim
76 words
A process in accordance with claim 6 wherein said first feedstock comprises the effluent from an electrochemical fluorination reaction cell utilizing anhydrous hydrogen fluoride (HF) as an electrolyte in the fluorination of a cell feedstock comprising dimethyl ether (F0), additionally comprising passing said second bottoms effluent stream into said electrochemical fluorination reaction cell to provide at least a portion of the dimethyl ether (F0) and anhydrous hydrogen fluoride (HF) requirements of said electrochemical fluorination reaction cell.
Claim 15
Dependent Claim
96 words
A process for the separation by extractive distillation of fluorinated dimethyl ether and anhydrous hydrogen fluoride, said process comprising: passing a feedstock stream comprising anhydrous hydrogen fluoride and at least one component selected from the group consisting of bis-difluoromethyl ether (F4) and monofluoromethyl difluoromethyl ether (F3) into an extractive distillation zone; passing a selective solvent stream comprising dimethyl ether (F0) into said extractive distillation zone; separating and withdrawing from said at least one component; and separating and withdrawing from said extractive distillation zone a bottoms effluent stream comprising dimethyl ether (F0) and anhydrous hydrogen fluoride (HF).
Claim 16
Dependent Claim
96 words
A process for the separation by extractive distillation of fluorinated dimethyl ether and anhydrous hydrogen fluoride, said process comprising: passing a feedstock stream comprising anhydrous hydrogen fluoride and at least one component selected from the group consisting of bis-difluoromethyl ether (F4) and monofluoromethyl difluoromethyl ether (F3) into an extractive distillation zone; passing a selective solvent stream comprising dimethyl ether (F0) into said extractive distillation zone; separating and withdrawing from said at least one component; and separating and withdrawing from said extractive distillation zone a bottoms effluent stream comprising dimethyl ether (F0) and anhydrous hydrogen fluoride (HF).
Claim 17
Dependent Claim
22 words
A process in accordance with claim 12 wherein said overhead effluent stream is at least substantially free of anhydrous hydrogen fluoride (HF).
Claim 18
Dependent Claim
40 words
A process in accordance with claim 12 wherein dimethyl ether (F0) and anhydrous hydrogen fluoride (HF) are present within said extractive distillation zone in a ratio by weight of F0:HF within the range of from about 1:10 to about 10:1.
Claim 19
Dependent Claim
58 words
A process in accordance with claim 14 wherein said ratio by weight of F0:HF is within the range of from about 1:3 to about 3: 1, wherein the temperatures within said extractive distillation zone are within the range of from about 10*C. to about 70*C., and wherein the pressure within said extractive distillation zone is about atmospheric pressure.
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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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |