次亜塩素酸イオンの陰極還元反応に及ぼすクロム酸塩添加の影響
摘要
The effect of chromate a【1dition on the suppression of hypochlorite reduction at a Pt cathode in alkaline solutions was examined，mainly by measurments of the rate of hydrogen evolution． As is well known，the chromate addition almost completely suppresses the reduction of hypochlorite．On the basis of polarograms and cyclic voltamograms，this effect was found to be based on the reduction of chromate to form a film composed of Cr［皿］． This effect was also shown even with8．g．，0．2mルf chromate solutions，much more dilute than usualy used in O．2ハ4hypochlorite solutions． In even more dilute chromate solutions，there was a sort of the induction period before the given degree of suppression was manifested，and this was considered to show that suppression did not begin to take place until the electrode was covered to a certain extent by the film． The delay before suppfession began was shorter as current density incτeased． The time required for complete suppression was in inverse pτoportion to chromate concentration，and the equation in l