Claims
- 1. A cathode suitable for use in an electrolytic cell used to produce halogen gas, hydrogen gas and alkali metal hydroxide solutions by electrolysis of alkali metal halide solutions, the cathode comprising a metallic-surfaced substrate having tightly adhered thereto a hard, substantially continuous and non-dendritic coating of electrocatalytic metal, the metallic-surfaced substrate being a metal which substantially retains its physical integrity during use as a cathode in the electrolytic cell, the coating having a substantially uniform composition and consisting essentially of a metal alloy of palladium, ruthenium, and optionally, at least one primary electrocatalytic metal selected from the group consisting of rhodium, osmium, iridium and platinum.
- 2. The cathode of claim 1 wherein the metallic-surfaced substrate comprises at least one metal selected from the group consisting of nickel, iron, steel, stainless steel, copper, and alloys thereof.
- 3. The cathode of claim 1 wherein the metallic-surfaced substrate is nickel.
- 4. The cathode of claim 1 wherein the metallic-surfaced substrate comprises a laminate consisting of a layer of metal selected from the group consisting of nickel, iron, steel, stainless steel, copper, and alloys thereof affixed to an underlying material.
- 5. The cathode of claim 1 wherein the metallic-surfaced substrate is in the form of an expanded mesh.
- 6. The cathode of claim 1 wherein the metallic-surfaced substrate is in the form of a woven wire screen.
- 7. The cathode of claim 1 wherein the coating has a thickness of from about 0.01 microns to about 15 microns.
- 8. The cathode of claim 1 wherein the coating has a thickness of from about 1 micron to about 3 microns.
- 9. The cathode of claim 1 wherein the coating comprises an amount of the primary electrocatalytic metals of from about 50 .mu.g/cm.sup.2 up to less than an excessive amount of the metals.
- 10. The cathode of claim 1 wherein the coating comprises an amount of the electrocatalytic metals of from about 800 .mu.g/cm.sup.2 to about 1,500 .mu.g/cm.sup.2.
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional of copending application Ser. No. 07/529,829 filed May 29, 1990.
US Referenced Citations (10)
Foreign Referenced Citations (5)
Number |
Date |
Country |
853686 |
Oct 1970 |
CAX |
0129088 |
May 1984 |
EPX |
0129374 |
May 1987 |
EPX |
0129231 |
Jan 1988 |
EPX |
45-11014 |
Apr 1970 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
529829 |
May 1990 |
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