Promotion of Pt-Ir catalytic electrodes with lead, tantalum, ruthenium and oxygen
US4426262A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1982 |
| Grant date | Jan 17, 1984 |
| Priority date | — |
| Expiry date | Apr 29, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25B11/093
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Platinum and iridium in catalytic electrodes for electrochemical uses is partially replaced with lead ruthenate-tantalum oxide composite. Electrodes are fabricated by first coating a film-forming metal substrate with a platinum-iridium composite undercoat, then overcoating with a composite containing lead, ruthenium, tantalum, platinum, iridium and oxygen. The most preferred anodes have a titanium substrate initially coated with approximately at least 2 gm/m.sup.2 of 70:30 .sup.w /o Pt:Ir composite, followed by about 20 gm/m.sup.2 of a composite having the nominal composition of 22.2.sup.w /o Pb.sub.2 Ru.sub.2 O.sub.6 ; 66.6 .sup.w /o Ta.sub.2 O.sub.5 ; 7.9 .sup.w /o Pt and 3.4 .sup.w /o Ir. The outer layer of the prepared anode contains from about 10 to about 16 .sup.w /o lead, from about 40 to about 65 .sup.w /o tantalum, from about 5 to about 7.5 .sup.w /o ruthenium, from about 6.0 to about 10 .sup.w /o platinum, from about 2.5 to about 5 .sup.w /o iridium, and from about 10 to about 20 .sup.w /o oxygen. These electrodes may be used in acidic, neutral or alkaline solutions. Typical uses include production of chlorine and chlorine compounds and electrowinning of metals, such as z…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.