Patent US4253935A successfully refreshed from Google Patents.
US4253935A
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US
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Method of preparing a diaphragm having a gel of a hydrous oxide or zirconium in a porous matrix
Assignee: PPG Industries Inc
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Filing: 1979-09-19
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Granted: 1981-03-03
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Expires: 1999-09-19
Abstract
Abstract Disclosed is a method of vacuum depositing zirconia and magnesia in a porous matrix to form a diaphragm.
Inventors
- 👤 Robert B. Simmons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:08
CPC Classifications
C; C25; C25B; C25B13/00; C25B13/04; C25B13/05; C25B13/07
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
128 words
In a method of preparing a diaphragm by contacting a porous matrix with zirconium oxychloride, and thereafter contacting the zirconium oxychloride containing porous matrix with an ammonium compound whereby to hydrolyze the zirconium oxychloride to form a substantially insoluble hydrous oxide of zirconium, the improvement comprising: a. inserting the porous matrix in a container containing an aqueous liquid composition of the zirconium oxychloride on only one surface of said porous matrix; b. drawing a vacuum on the surface of said porous matrix opposite the surface contacting the aqueous liquid composition and thereafter releasing the vacuum, whereby to evacuate the porous matrix and draw the aqueous liquid composition into the porous matrix; and c. thereafter allowing an ammonium compound to penetrate the porous matrix to hydrolyze the zirconium oxychloride.
Claim 2
Dependent Claim
128 words
In a method of preparing a diaphragm by contacting a porous matrix with zirconium oxychloride, and thereafter contacting the zirconium oxychloride containing porous matrix with an ammonium compound whereby to hydrolyze the zirconium oxychloride to form a substantially insoluble hydrous oxide of zirconium, the improvement comprising: a. inserting the porous matrix in a container containing an aqueous liquid composition of the zirconium oxychloride on only one surface of said porous matrix; b. drawing a vacuum on the surface of said porous matrix opposite the surface contacting the aqueous liquid composition and thereafter releasing the vacuum, whereby to evacuate the porous matrix and draw the aqueous liquid composition into the porous matrix; and c. thereafter allowing an ammonium compound to penetrate the porous matrix to hydrolyze the zirconium oxychloride.
Claim 3
Dependent Claim
14 words
The method of claim 1 comprising leaching the porous matrix with water after hydrolysis.
Claim 4
Dependent Claim
20 words
The method of claim 1 comprising drawing a vacuum of at least about 500 millimeters of mercury across the matrix.
Claim 5
Dependent Claim
19 words
The method of claim 3 comprising maintaining the vacuum across the porous matrix for at least about two minutes.
Claim 6
Dependent Claim
21 words
The method of claim 4 comprising releasing the vacuum at a rate of less than 100 millimeters of mercury per second.
Claim 7
Dependent Claim
16 words
The method of claim 3 comprising drawing and retaining the vacuum at least twice in succession.
Claim 8
Dependent Claim
25 words
The method of claim 1 comprising depositing at least 50 grams of zirconium, calculated as ZrO 2 , per square foot, on the porous matrix.
Claim 9
Dependent Claim
29 words
The method of claim 1 comprising passing about 1 to 10 grams of the ammonium compound, calculated as NH 3 , through the porous matrix, per gram of oxides.
Claim 10
Dependent Claim
20 words
The method of claim 1 comprising passing the ammonium compound through the porous matrix for about 2 to 6 hours.
Claim 11
Dependent Claim
28 words
The method of claim 1 comprising passing about 0.5 to about 25 kilograms of ammonia compound, calculated as NH 3 , through the porous matrix, per square foot.
Claim 12
Dependent Claim
29 words
The method of claim 1 wherein the porous matrix is formed of a material chosen from the group consisting of asbestos, halocarbon fibers, porous halocarbon sheets, and ceramic fibers.
Claim 13
Dependent Claim
16 words
The method of claim 1 wherein the porous matrix has a coating of a hydrophilic resin.
Claim 14
Dependent Claim
20 words
The method of claim 1 wherein the aqueous liquid composition of zirconium hydroxide comprises ZrO 2 , HCl, and water.
Claim 15
Dependent Claim
15 words
The method of claim 13 wherein the aqueous liquid composition of zirconium hydroxide comprises MgO.
Claim 16
Dependent Claim
27 words
The method of claim 14 wherein the weight ratio of zirconia to total magnesia and zirconia in the porous matrix is from about 0.70 to about 0.995.
Claim 17
Dependent Claim
11 words
The method of claim 1 wherein the porous matrix is vertical.
References Cited (Backward Citations)
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US3479267A
Cited
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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) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |