US3926799A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Support for dynamic membrane
Assignee: United States Department of the Interior
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Filing: 1974-09-24
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Granted: 1975-12-16
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Expires: 1994-09-24
Abstract
Abstract Porous supports for dynamic hyperfiltration membranes are prepared by coating substrates with ZrO2 filter aid prior to insertion in desalination apparatus. The coating is applied by applying a layer of an aqueous slurry of ZrO2 to the substrate, followed by drying and firing the resulting composite.
Inventors
- 👤 David G Thomas
- 👤 William R Mixon
- 👤 Phil H Hayes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:54
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/14; B01D69/141; B01D69/142; B01D67/00; B01D67/0039; B01D67/0046; B01D69/10; B01D69/108; B01D71/00; B01D71/02; B01D71/024; B01D2323/00; B01D2323/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
94 words
A METHOD FOR PREPARATION OF A COMPOSITE SUPPORT FOR A DYNAMIC HYPERFILTRATION MEMBRANE COMPRISING COATING A POROUS SUBSTRATE WITH AN ESSENTIALLY UNIFORM LAYER OF ZIRCONIUM OXIDE BY APPLYING TO THE SUBSTRATE A LAYER OF AN AQUEOUS SLURRY OF ZIRCONIUM OXIDE, THE PARTICLE SIZE OF THE ZIRCONIUM OXIDE BEING ABOUT 1.5 TO 30 MICRONS AND THE CONCENTRATION OF THE ZIRCONIUM OXIDE IN THE SLURRY BEING ABOUT 30 TO 60 WEIGHT PERCENT; DRYING AT ROOM TEMPERTURE; AND FIRING AT A TEMPERATURE 0F 900* TO 1400*C TO FORM A DURABLE LAYER OF ZIRCONIUM OXIDE ON THE SUBSTRATE.
Claim 2
Independent Claim
94 words
A METHOD FOR PREPARATION OF A COMPOSITE SUPPORT FOR A DYNAMIC HYPERFILTRATION MEMBRANE COMPRISING COATING A POROUS SUBSTRATE WITH AN ESSENTIALLY UNIFORM LAYER OF ZIRCONIUM OXIDE BY APPLYING TO THE SUBSTRATE A LAYER OF AN AQUEOUS SLURRY OF ZIRCONIUM OXIDE, THE PARTICLE SIZE OF THE ZIRCONIUM OXIDE BEING ABOUT 1.5 TO 30 MICRONS AND THE CONCENTRATION OF THE ZIRCONIUM OXIDE IN THE SLURRY BEING ABOUT 30 TO 60 WEIGHT PERCENT; DRYING AT ROOM TEMPERTURE; AND FIRING AT A TEMPERATURE 0F 900* TO 1400*C TO FORM A DURABLE LAYER OF ZIRCONIUM OXIDE ON THE SUBSTRATE.
Claim 3
Dependent Claim
15 words
The method of claim 1 in which the porous substrate consists of a ceramic tube.
Claim 4
Dependent Claim
10 words
The composite support prepared by the method of claim 1.
Claim 5
Dependent Claim
36 words
In a process for purifying water by hyperfiltration comprising passing the water, under pressure, over the surface of a hyperfiltration membrane, the improvement comprising using the composite support of claim 3 to support the hyperfiltration membrane.
Claim 6
Dependent Claim
16 words
The process of claim 4 in which the hyperfiltration membrane is formed dynamically on the support.
Claim 7
Dependent Claim
21 words
The process of claim 5 in which the membrane consists essentially of a combination of hydrous zirconium oxide and polyacrylic acid.
References Cited (Backward Citations)
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 |