DETECTION OF IONS IN CHROMIUM DISSOLUTION USING CHANNEL FLOW MULTIELECTRODE

The anodic dissolution mechanism of chromium in acidic sulphate soluti on was studied using a channel flow multi-electrode system. In the pot ential region for active dissolution, dissolved chromous ions from the chromium working electrode were collected on the Sold collector elect rode at 0.5V by the oxidation reaction to chromic ions. The experiment al collection efficiency was much smaller than the theoretical one, be cause chemical reaction of dissolved chromous ions took place in the s olution and activity of the collector electrode decreased due to cover age of the reaction product on the collector electrode surface. Activa tion of the collector electrode at 1.5V led that the collection effici ency for chromouos ions recovered approximately to the theoretical one s. The Tafel slope of the collected chromous ions was found as 0.060V/ decade.