水銀のストリッピング・ボルタンメトリーにおける微量塩素の影響
1976 年 25 巻 6 号 p. 402-404
詳細
1976 年 25 巻 6 号 p. 402-404
In anodic stripping voltammetry of mercury in perchloric acid solutions with a glassy carbon electrode, the main stripping peak was sometimes accompanied by a small preceding secondary peak, whose nature was not clearly understood. It was proved that the secondary peak was due to traces of chloride ion. The effects of chloride ion concentration, scan rate, pre-electrolysis time, and stirring rate on the mercury stripping peaks, showed that chloride ions in solution diffuse to the electrode and mercury(I) chloride is formed, on the anodic stripping process, at a potential more negative than that of the stripping of mercury. Both the main peak height and the total peak area decreased rapidly with increasing chloride ion concentration up to about 3μg Cl- per 14 ml. The effect became less marked at higher chloride concentrations. An addition of proper amounts of chloride ion {(1020)μg per 14 ml} to the electrolyte may be useful to obtain better precision and accuracy in the determination of mercury(II) by the stripping voltammetry.
