US4719062A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extractant-surfactant post-treatments of permselective composite membranes
Assignee: EIDP Inc
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Filing: 1986-04-23
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Granted: 1988-01-12
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Expires: 2006-04-23
Abstract
Abstract A treatment process for treating an interfacially polymerized polyaramide on a microporous support reverse osmosis membrane. The treatment involves immersing the membrane in an aqueous solution containing 5 to 25 weight percent of an alcohol having 1-5 carbon atoms for 15 minutes to two hours at a pressure of 50 to 100 psi. Optionally, the membrane can be treated with a surfactant.
Inventors
- 👤 Sherman A. Sundet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:19
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0088; B01D69/00; B01D69/12; B01D69/125; B01D69/1251; B01D71/00; B01D71/06; B01D71/56
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
58 words
A process for improving the flux of an interfacially polymerized polyaramide permselective membrane supported on a microporous support comprising contacting said membrane with an aqueous solution of 2.5 to 25 weight percent of an alcohol having 1 to 5 carbon atoms, under a pressure of 50 to 250 psi for a period of 15 minutes to two hours.
Claim 2
Dependent Claim
58 words
A process for improving the flux of an interfacially polymerized polyaramide permselective membrane supported on a microporous support comprising contacting said membrane with an aqueous solution of 2.5 to 25 weight percent of an alcohol having 1 to 5 carbon atoms, under a pressure of 50 to 250 psi for a period of 15 minutes to two hours.
Claim 3
Dependent Claim
37 words
The process of claim 1 wherein the polyamide is formed by interfacially polymerizing m-phenylenediamine with at least 50 weight percent, based on acid halide trimesoyl chloride or cyclohexane-1,3,5-tricarbonyl chloride and the remainder isophthaloyl chloride or terephthaloyl chloride.
Claim 4
Dependent Claim
15 words
The process of claim 2 wherein the alcohol contains from 1 to 4 carbon atoms.
Claim 5
Dependent Claim
23 words
The process of claim 3 wherein 10 to 10,000 ppm based on the solution of a surfactant is also applied to the membrane.
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) | 1991-01-11 | 1991-07-13 | 1992-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-11 | 1995-07-13 | 1996-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-11 | 1999-07-13 | 2000-01-12 | $7700.00 | Window Closed / Lapsed |