Ruthenium Dioxide as Cathode Material for Hydrogen Evolution in Hydroxide and Chlorate Solutions

• Ruthenium dioxide as electrocatalyst on an activated cathode for chlorate production was investigated with respect toits activity towards hydrogen evolution, hypochlorite reduction, and chlorate reduction, respectively. Investigations weremade in the presence, as well as in the absence, of a chromium hydroxide film in 1M NaOH and in typical chlorateelectrolyte. Low overvoltages for hydrogen evolution were found and, at technical current densities, an effect of catalystcoating thickness. Commercial DSA® electrodes with RuO2 as the active compound were tested as cathodes and were lessactive but more stable than the coatings produced by us. Hypochlorite and chlorate were reduced in the absence ofchromate, chlorate reduction being fast on ruthenium dioxide compared to the other electrode materials and by far thedominating cathodic reaction in chlorate electrolyte without chromate and hypochlorite at 70°C, 3 kA/m2

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Keyword

catalysts; catalysis; ruthenium compounds; oxygen compounds; electrochemistry; electrochemical electrodes; reduction (chemical); reaction kinetics

Chemical engineering

Kemiteknik

Publication and Content Type

ref (subject category)

art (subject category)