亜鉛電解におけるコバルトの挙動に関する研究 (第1報)

コバルトIII価の生成, 分解及びその陰極電流効率に及ぼす影響

抄録

Although it has been generally presumed that the some portion of the cobalt (II) in the electrolyte oxidized at the anode to cobalt (III) during the electrodeposition ofzinc, this phenomenon has not been studied systematically.
We studied systematically on the formation and the decomposition of cobalt (III) which are formed in the electrolytes during the zinc electrodeposition, and on the effects of cobalt (II) and cobalt (III) to the cathodic carrent efficiencies at the beginning of the zinc electrodeposition under the different conditions.
We obtained the following results;
(1) The characteristic on the definite absorption wave length, 40mμ and 600mμ of cobalt (III) in zinc sulphate electrolyte could be observed by the spectrophotometry.
(2) The concentration of cobalt (III) increses for some hours at the initial stage of the electrolysis, and then decreases afterwards.
(3) The decomposition of cobalt (III) in zinc sulphate electrolyte is easier in chemicals than in electrochemicals.
(4) The cathodic current efficiency in the case of the electrolyte containing cobalt (III) is hipher than containing cobalt (I), but is lower than the absence of cobalt. These results seem to differ above the temperature of 45°C.