US3651618A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of fluids by diffusion through semipermeable membranes
Assignee: Linde GmbH
•
Filing: 1970-05-20
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Granted: 1972-03-28
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Expires: 1990-05-20
Abstract
Abstract In a process comprising diffusing a fluid through the upstream side of a semipermeable membrane having upstream and downstream sides, to the downstream side, the improvement comprising exposing the downstream side during said diffusing to either a liquid which does not wet the downstream side, or to the vapor of said liquid, whereby the rate of diffusion of said fluid through said membrane is increased and wherein said semipermeable membrane is a microporous sintered material, e.g., polytetrafluoroethylene having a pore diameter of 1-1,000, preferably 5-200 microns.
Inventors
- 👤 Gunter Klein
- 👤 Johann Neumann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:18
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/22; B01D53/225; B01D53/226
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
30 words
A process as defined by claim 1 wherein said fluid is a mixture of components having different diffusivities, whereby said fluid is enriched in at least one of said components.
Claim 2
Dependent Claim
14 words
A process according to claim 1 wherein the membrane is a lyophobic organic polymer.
Claim 3
Dependent Claim
28 words
A process according to claim 1 wherein the membrane is a sintered hydrophobic synthetic material and is exposed on the downstream side to liquid water or saturated steam.
Claim 4
Dependent Claim
12 words
A process according to claim 1 wherein said fluid is normally gaseous.
Claim 5
Dependent Claim
22 words
A process according to claim 1, further comprising maintaining a temperature gradient across the membrane, the downstream side having the higher temperature.
Claim 6
Dependent Claim
22 words
A process according to claim 1, further comprising maintaining a pressure gradient across the membrane, the downstream side having the higher pressure.
Claim 7
Dependent Claim
13 words
A process according to claim 1 wherein the membrane has a textured surface.
Claim 8
Dependent Claim
96 words
Apparatus suitable for separating a gas into its components, said apparatus comprising a plurality of diffusion cells, each of said cells being subdivided into a gas feed chamber and a gas discharge chamber by a microporous sintered plastic membrane, with said chamber being provided with conduit means for effecting series communication between said cells, said conduit means comprising conduit for connecting the gas discharge chamber of each diffusion cell disposed upstream with the gas feed chamber of the subsequent diffusion cell, and further comprising cooler means and expansion valve disposed serially in association with said conduit.
Claim 9
Dependent Claim
36 words
Apparatus according to claim 9, said conduit means further comprising conduit between the gas feed chamber of each diffusion cell with the gas feed chamber of each diffusion cell arranged upstream thereof in the gaseous flowpath.
Claim 10
Dependent Claim
19 words
A process as defined by claim 1, said membrane having micropores of about 1 to 1,000 microns in diameter.
Claim 11
Dependent Claim
19 words
A process as defined by claim 1, said membrane having micropores of about 5 to 200 microns in diameter.
Claim 12
Dependent Claim
12 words
A process as defined by claim 1, said membrance consisting of polytetrafluoroethylene.
Claim 13
Dependent Claim
12 words
A process as defined by claim 11, said membrane consisting of polytetrafluoroethylene.
Claim 14
Dependent Claim
18 words
A process as defined by claim 1, said membrane comprising at least 50 percent by volume of polytetrafluoroethylene.
Claim 15
Dependent Claim
18 words
A process as defined by claim 1, said membrane comprising at least 70 percent by volume of polytetrafluoroethylene.
Claim 16
Dependent Claim
28 words
A process as defined by claim 1, said downstream side of said membrane being exposed to said vapor of a liquid which does not wet the downstream side.
Claim 17
Dependent Claim
29 words
A process as defined by claim 17, said membrane comprising at least 50 percent by volume of polytetrafluoroethylene and having micropores of a diameter of 1 to 1,000 microns.
Claim 18
Dependent Claim
15 words
A process as defined by claim 1, said upstream side of said membrane being dry.
Claim 19
Dependent Claim
29 words
A process as defined by claim 19, said membrane comprising at least 50 percent by volume of polytetrafluoroethylene and having micropores of a diameter of 1 to 1,000 microns.
References Cited (Backward Citations)
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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) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |