Patent US6730016B1 successfully refreshed from Google Patents.
US3554379A
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US
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Desalination apparatus and process of manufacture using improved, nitrogenous membranes
Assignee: EIDP Inc
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Filing: 1969-06-10
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Granted: 1971-01-12
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Expires: 1989-06-10
Abstract
Abstract Selectively permeable membranes comprising substantially linear nitrogeneous polymers grafted with polymerizable unsaturated organic acids are chemically treated to convert free acid groups present into forms exhibiting a lesser degree of hydrophilicity, such as polyvalent metal salt forms or nonacidic derivative forms. The inventive treatment reduces the tendency of such membranes for swelling or dimensional change in water and thereby makes practical the assembly and operation of permeation separation apparatus in which they are incorporated either in the form of a flat film or in the form of a hollow fiber or capillary.
Inventors
- 👤 Donald George Pye
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:39
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0093; B01D63/00; B01D63/02; B01D63/021; B01D63/022; B01D65/00; B01D65/003; B01D71/00; B01D71/06; B01D71/56; B01D2323/00; B01D2323/38; Y; Y02; Y02A; Y02A20/00; Y02A20/124; Y02A20/131
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
72 words
A process according to claim 1 wherein said polymers are characterized by recurring atoms as an integral part of the polymer chain and bearing at least about 300 titratable acid groups per million grams of polymer, at least about 200 of said acid groups being chemically bonded by a carbon-to-carbon linkage to a catenarian carbon atom of said polymer and removed by at least one carbon atom from said catenarian carbon atom.
Claim 2
Dependent Claim
30 words
A process according to claim 2 wherein conversion is effected with a treating agent selected from the group consisting of salts of polyvalent metals, organic isocyanates, diazomethane, and hydrazoic acid.
Claim 3
Dependent Claim
50 words
A process according to claim 2 wherein conversion is effected by exposing said membranes to a treating agent comprising an organic isocyanate at a temperature between about 100* C. and about 150* C. for a period of time between 1 and 6 hours and subsequently exposing the membranes to water.
Claim 4
Dependent Claim
13 words
A process according to claim 4 wherein said treating agent is in solution.
Claim 5
Dependent Claim
42 words
A reverse osmosis membrane of an acid grafted, substantially linear nitrogenous polymer, at least a portion of said polymer comprising less hydrophilic groups in substitution of its free acid groups and being characterized by a reduced tendency for dimensional change in water.
Claim 6
Dependent Claim
72 words
A membrane according to claim 6 wherein said polymer is characterized by recurring atoms as an integral part of the polymer chain and bearing at least about 300 titratable acid groups per million grams of polymer, at least about 200 of said acid groups being chemically bonded by a carbon-to-carbon linkage to a catenarian carbon atom of said polymer and removed by at least one carbon atom from said catenarian carbon atom.
Claim 7
Dependent Claim
17 words
A membrane according to claim 6 wherein said less hydrophilic groups comprise a polyvalent metal salt form.
Claim 8
Dependent Claim
16 words
A membrane according to claim 6 wherein said less hydrophilic groups comprise a derivative ester form.
Claim 9
Dependent Claim
16 words
A membrane according to claim 6 wherein said less hydrophilic groups comprise a derivative amine form.
Claim 10
Dependent Claim
16 words
A membrane according to claim 6 wherein said less hydrophilic groups comprise a derivative amide form.
Claim 11
Dependent Claim
80 words
In a permeation separation apparatus adapted for the reverse osmosis separation of components of aqueous solutions and mixtures and comprising at least one cast wall member in sealing relationship with a plurality of selectively permeable, capillary membranes of an acid grafted, substantially linear nitrogenous polymer, the improvement wherein the polymer in the sealing areas of said membranes is characterized by a reduced tendency for dimensional change in water and comprises less hydrophilic groups in substitution of its free acid groups.
Claim 12
Dependent Claim
72 words
An apparatus according to claim 12 wherein said polymer is characterized by recurring atoms as an integral part of the polymer chain and bearing at least about 300 titratable acid groups per million grams of polymer, at least about 200 of said acid groups being chemically bonded by a carbon-to-carbon linkage to a catenarian carbon atom of said polymer and removed by at least one carbon atom from said catenarian carbon atom.
Claim 13
Dependent Claim
17 words
An apparatus according to claim 13 wherein said less hydrophilic groups comprise a polyvalent metal salt form.
Claim 14
Dependent Claim
16 words
An apparatus according to claim 13 wherein said less hydrophilic groups comprise a derivative ester form.
Claim 15
Dependent Claim
16 words
An apparatus according to claim 13 wherein said less hydrophilic groups comprise a derivative amine form.
Claim 16
Dependent Claim
16 words
An apparatus according to claim 13 wherein said less hydrophilic groups comprise a derivative amide form.
Claim 17
Dependent Claim
72 words
In a process for assembling a permeation separation apparatus, the steps comprising assembling into a bundle a plurality of reverse osmosis membranes comprising hollow filaments of a subsTantially linear nitrogenous polymer and having grafted acid groups over their entire lengths, treating a portion of said bundle to convert the free acid groups present in said portion to less hydrophilic groups, and encapsulating the treated portion of said bundle with a potting compound.
Claim 18
Dependent Claim
72 words
A process according to claim 18 wherein said polymer is characterized by recurring atoms as an integral part of the polymer chain and bearing at least about 300 titratable acid groups per million grams of polymer, at least about 200 of said acid groups being chemically bonded by a carbon-to-carbon linkage to a catenarian carbon atom of said polymer and removed by at least one carbon atom from said catenarian carbon atom.
Claim 19
Dependent Claim
17 words
A process according to claim 19 wherein said less hydrophilic groups comprise a polyvalent metal salt form.
Claim 20
Dependent Claim
16 words
A process according to claim 19 wherein said less hydrophilic groups comprise a derivative ester form.
Claim 21
Dependent Claim
16 words
A process according to claim 19 wherein said less hydrophilic groups comprise a derivative amine form.
Claim 22
Dependent Claim
16 words
A process according to claim 19 wherein said less hydrophilic groups comprise a derivative amide form.
References Cited (Backward Citations)
US3140256A
Cited
US3423491A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |