Determination of Traces of Cobalt in Zinc Matrix by Catalytic Adsorptive Stripping Voltammetry at Bismuth Film Electrode

Abstract An catalytic adsorptive stripping voltammetric procedure for the determination of cobalt in a zinc matrix at an in situ plated bismuth film electrode was described. The procedure exploits the enhancement effect of a cobalt peak observed in the system Co(II)–dimethylglyoxime–piperazine‐1,4‐bis(2‐ethanesulfonic acid)–cetyltrimethylammonium bromide. Using optimized conditions, in a solution containing 0.01 mol L−1 Zn(II) the calibration plot for Co(II) following accumulation time of 120 s was linear from 2×10−10 to 5×10−8 mol L−1. The detection limit (based on 3σ criterion) for Co(II) of 6×10−11 mol L−1 was achieved. The proposed procedure was applied for Co(II) determination in zinc reagent for analysis and in tap water.