Patent US3853721A successfully refreshed from Google Patents.
US3853721A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for electrolysing brine
Assignee: PPG Industries Inc
•
Filing: 1972-10-24
•
Granted: 1974-12-10
•
Expires: 1992-10-24
Abstract
Abstract Novel diaphragms for use in chlor-alkali cells are disclosed. The diaphragms are electrolyte-permeable, asbestos diaphragms having an organic, ion exchange resin contained therein. Also disclosed is the electrolysis of brines in an electrolytic cell having such a diaphragm and a method of preparing and installing such diaphragms. Additionally, there is also disclosed a particularly adherent fluorocarbon coating on asbestos.
Inventors
- 👤 W Darlington
- 👤 R Foster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:30
CPC Classifications
C; C25; C25B; C25B13/00; C25B13/04; C25B13/08; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C25B13/05; C25B13/06
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
117 words
IN A PROCESS FOR ELECTRLYZING ALKALI METAL CHLORIDE BRINES IN AN ELECTRLYTIC CELL HAVING AN ANOLYTTE COMPARTMENT AND A CATHOLYTE COMPARTMENT SEPARATED THEREFROM BY AN ALKALI METAL CHLORIDE BRINE PERMEABLE, FLUOROCARBON RESIN CONTAINING, ASBESTOS DISPHRAGM, WHEREIN ALKALI METAL CHLORIDE BRINE IS FED TO SAID CELL AND CATHOLYTE LIQUOR CONTAINING ALKALI METAL CHLORIDE AND ALKALI METAL HYDROXIDE IS RECOVERED FROM SAID CELL, THE IMPROVEMENT WHEREIN SAID DISPHRAGM CONTAINS FROM ABOUT 0.01 TO ABOUT 22 WEIGHT PERCENT OF FLUOROCARBON RESIN, THE FLUOROCARBON RESIN BEING DISPERSED INTO THE DIAPHRAGM TO A DEPTH OF AT LEAST 0.08 INCH FROM ONE SURFACE THEREOF, SAID FLUOROCARBON RESIN PROVIDING A COATING ON INDIVIDUAL ABSESTOS FIBER BUNDLES, AND SAID FLUOROCARBON RESIN HAVING THE EMPIRICAL FORMULA:
Claim 2
Dependent Claim
117 words
IN A PROCESS FOR ELECTRLYZING ALKALI METAL CHLORIDE BRINES IN AN ELECTRLYTIC CELL HAVING AN ANOLYTTE COMPARTMENT AND A CATHOLYTE COMPARTMENT SEPARATED THEREFROM BY AN ALKALI METAL CHLORIDE BRINE PERMEABLE, FLUOROCARBON RESIN CONTAINING, ASBESTOS DISPHRAGM, WHEREIN ALKALI METAL CHLORIDE BRINE IS FED TO SAID CELL AND CATHOLYTE LIQUOR CONTAINING ALKALI METAL CHLORIDE AND ALKALI METAL HYDROXIDE IS RECOVERED FROM SAID CELL, THE IMPROVEMENT WHEREIN SAID DISPHRAGM CONTAINS FROM ABOUT 0.01 TO ABOUT 22 WEIGHT PERCENT OF FLUOROCARBON RESIN, THE FLUOROCARBON RESIN BEING DISPERSED INTO THE DIAPHRAGM TO A DEPTH OF AT LEAST 0.08 INCH FROM ONE SURFACE THEREOF, SAID FLUOROCARBON RESIN PROVIDING A COATING ON INDIVIDUAL ABSESTOS FIBER BUNDLES, AND SAID FLUOROCARBON RESIN HAVING THE EMPIRICAL FORMULA:
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein said diaphragm contains from about 0.3 to about 7.0 weight percent of fluorocarbon resin.
Claim 4
Dependent Claim
26 words
The of claim ofclaim 1 wherein said fluorocarbon resin is dispersed into said diaphragm to a depth of at least 0.15 inch from one surface thereof.
Claim 5
Dependent Claim
26 words
The process of claim 1 wherein said diaphragm contains from about 0.01 gram to about 10 grams of fluorocarbon resin per square foot of diaphragm area.
Claim 6
Dependent Claim
55 words
The process of claim 1 wherein brine containing from about 280 to about 315 grams per liter of sodium chloride is fed to said cell and a catholyte liquor containing from about 7 to about 15 weight percent sodium chloride and about 10 to about 15 weight percent sodium hydroxide is recovered from said cell.
Claim 7
Independent Claim
58 words
A method of reducing the voltage drop across a sodium chloride brine permeable, fluorocarbon containing, asbestos diaphragm of a chlor-alkali cell while maintaining its physical strength during its use over extended periods of electrolysis, said method comprising providing as the fluorocarbon from about 0.01 to 22 weight percent basis total diaphragm, a hydrophilic fluorocarbon having the empirical formula:
Claim 8
Independent Claim
58 words
A method of reducing the voltage drop across a sodium chloride brine permeable, fluorocarbon containing, asbestos diaphragm of a chlor-alkali cell while maintaining its physical strength during its use over extended periods of electrolysis, said method comprising providing as the fluorocarbon from about 0.01 to 22 weight percent basis total diaphragm, a hydrophilic fluorocarbon having the empirical formula:
Claim 9
Dependent Claim
20 words
The method of claim 6 wherein said diaphgram contains from about 0.3 to about 7.0 weight percent of hydrophilic fluorocarbon.
Claim 10
Dependent Claim
26 words
The method of claim 6 wherein said diaphgram contains from about 0.01 gram to about 10.0 grams of hydrophilic fluorocarbon per square foot of diaphragm area.
Claim 11
Dependent Claim
26 words
The method of claim 6 wherein said hydrophilic fluorocarbon is dispersed into said diaphragm to a depth of at least 0.08 inch from one surface thereof.
Claim 12
Dependent Claim
26 words
The method of claim 9 wherein said hydrophilic fluorocarbon is dispersed into said diaphragm to a depth of at least 0.15 inch from one surface thereof.
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) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |