Patent US3923315A successfully refreshed from Google Patents.
Patent US3926798A successfully refreshed from Google Patents.
US3926798A
Expired / Lapsed
US
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Reverse osmosis membrane
Assignee: United States Department of the Interior
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Filing: 1974-10-17
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Granted: 1975-12-16
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Expires: 1994-10-17
Abstract
Abstract A reverse osmosis membrane is prepared by in situ polymerization of furfuryl alcohol on a porous support.
Inventors
- 👤 John E Cadotte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:17
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/12; B01D69/125
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
57 words
A PROCESS FOR PREPARATION OF A COMPOSITE REVERSE OSMOSIS MEMBRANE COMPRISING: COATING A MICROPOROUS SUPPORT WITH AN AQUEOUS SOLUTION OF FURFURYL ALCOHOL AND AN ACID CATALYST CAPABLE OF POLYMERIZING THE FURFURYL ALCOHOL; HEATING TO POLYMERIZE THE FURFURYL ALCOHOL; AND CURING AT A TEMPERATURE OF ABOUT 110* TO 160*C FOR A PERIOD OF ABOUT 1 TO 30 MINUTES.
Claim 2
Dependent Claim
57 words
A PROCESS FOR PREPARATION OF A COMPOSITE REVERSE OSMOSIS MEMBRANE COMPRISING: COATING A MICROPOROUS SUPPORT WITH AN AQUEOUS SOLUTION OF FURFURYL ALCOHOL AND AN ACID CATALYST CAPABLE OF POLYMERIZING THE FURFURYL ALCOHOL; HEATING TO POLYMERIZE THE FURFURYL ALCOHOL; AND CURING AT A TEMPERATURE OF ABOUT 110* TO 160*C FOR A PERIOD OF ABOUT 1 TO 30 MINUTES.
Claim 3
Dependent Claim
14 words
The process of claim 1 in which the support consists of a polysulfone film.
Claim 4
Dependent Claim
32 words
The process of claim 1 in which the catalyst is selected from the group consisting of sulfuric acid, methane sulfonic acid, toluene sulfonic acid, benzene disulfonic acid, phosphoric acid and hydrochloric acid.
Claim 5
Dependent Claim
12 words
The process of claim 3 in which the catalyst is sulfuric acid.
Claim 6
Dependent Claim
12 words
A composite reverse osmosis membrane prepared by the process of claim 1.
Claim 7
Dependent Claim
37 words
In a process for desalination of saline water by reverse osmosis comprising contacting the saline water under pressure with a reverse osmosis membrane, the improvement comprising using the membrane of claim 5 as the reverse osmosis membrane.
References Cited (Backward Citations)
US3088791A
Cited
US3615024A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |