Patent US4462877A successfully refreshed from Google Patents.
US4462877A
Expired / Lapsed
US
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Composite ion exchange membranes
Assignee: Dow Chemical Co
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Filing: 1982-03-26
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Granted: 1984-07-31
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Expires: 2002-03-26
Abstract
Abstract A composite, substantially completely fluorinated film containing ion exchange groups and its use as an ion exchange membrane in an electrolytic cell is described. The membranes are comprised of at least two layers wherein the layers have equivalent weights that differ by less than 150 and contain ion exchange groups. When each layer contains sulfonyl ion exchange groups the equivalent weight of the two layers differ by less than 250. When the equivalent weight difference exceeds 250, at least one layer has an equivalent weight of less than 1000. The higher equivalent weight layer should face the cathode in an electrolytic cell. When the first layer contains carboxylic acid ion exchange groups and the second layer contains sulfonyl ion exchange groups, at least one layer has an equivalent weight of less than 1000. The carboxylic acid containing layer faces the cathode in an electrolytic cell.
Inventors
- 👤 Bobby R. Ezzell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:35
CPC Classifications
C; C25; C25B; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2275; C08J5/2281; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
34 words
A process which comprises electrolyzing an aqueous electrolyte between a pair of electrodes separated by a substantially completely fluorinated composite ion exchange membrane having two layers differing in equivalent weight by less than 150.
Claim 2
Dependent Claim
34 words
A process which comprises electrolyzing an aqueous electrolyte between a pair of electrodes separated by a substantially completely fluorinated composite ion exchange membrane having two layers differing in equivalent weight by less than 150.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the aqueous electrolyte is an alkali metal halide solution.
Claim 4
Dependent Claim
29 words
The process of claim 1 wherein at least one of the electrodes is a cathode and the ion exchange membrane layer having the higher equivalent weight faces the cathode.
Claim 5
Dependent Claim
39 words
A process comprising electrolyzing an aqueous electrolyte between a pair of electrodes separated by a substantially completely fluorinated composite ion exchange membrane having sulfonyl ion exchange functionality and having two layers differing in equivalent weight by less than 250.
Claim 6
Dependent Claim
39 words
A process comprising electrolyzing an aqueous electrolyte between a pair of electrodes separated by a substantially completely fluorinated composite ion exchange membrane having sulfonyl ion exchange functionality and having two layers differing in equivalent weight by less than 250.
Claim 7
Dependent Claim
29 words
The process of claim 4 wherein at least one of the electrodes is a cathode and the ion exchange membrane layer having the higher equivalent weight faces the cathode.
Claim 8
Dependent Claim
15 words
The process of claim 4 wherein the aqueous electrolyte is a alkali metal halide solution.
Claim 9
Dependent Claim
57 words
A process which comprises electrolyzing an aqueous electrolyte between a pair of electrodes which are separated by a substantially completely fluorinated composite ion exchange membrane having a first layer containing carboxylic acid ion exchange groups and a second layer containing sulfonyl ion exchange groups, wherein at least one layer has an equivalent weight of less than 1,000.
Claim 10
Dependent Claim
57 words
A process which comprises electrolyzing an aqueous electrolyte between a pair of electrodes which are separated by a substantially completely fluorinated composite ion exchange membrane having a first layer containing carboxylic acid ion exchange groups and a second layer containing sulfonyl ion exchange groups, wherein at least one layer has an equivalent weight of less than 1,000.
Claim 11
Dependent Claim
15 words
The process of claim 7 wherein the aqueous electrolyte is an alkali metal halide solution.
Claim 12
Dependent Claim
18 words
The process of claim 7 wherein the first layer of the ion exchange membrane faces the cathode compartment.
Claim 13
Dependent Claim
17 words
The process of claim 7 wherein the first layer has an equivalent weight of less than 1,000.
Claim 14
Dependent Claim
66 words
A process comprising electrolyzing an aqueous electrolyte between a pair of electrodes which are separated by a substantially completely fluorinated composition exchange membrane having a first layer containing sulfonyl ion exchange functionality and a second layer containing sulfonyl ion exchange functionality, wherein at least one layer has an equivalent weight of less than 1,000 and the two layers differ in equivalent weight by at least 250.
Claim 15
Dependent Claim
66 words
A process comprising electrolyzing an aqueous electrolyte between a pair of electrodes which are separated by a substantially completely fluorinated composition exchange membrane having a first layer containing sulfonyl ion exchange functionality and a second layer containing sulfonyl ion exchange functionality, wherein at least one layer has an equivalent weight of less than 1,000 and the two layers differ in equivalent weight by at least 250.
Claim 16
Dependent Claim
15 words
The process of claim 11 wherein the aqueous electrolyte is an alkali metal halide solution.
Claim 17
Dependent Claim
30 words
The process of claim 11 wherein in at least one of the electrode is a cathode and the ion exchange membrane layer having the higher equivalent weight faces the cathode.
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) | 1987-07-31 | 1988-01-30 | 1988-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-31 | 1992-01-30 | 1992-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-31 | 1996-01-30 | 1996-07-31 | $7700.00 | Window Closed / Lapsed |