An indirect voltammetric approach for the determination of cyanide at a chemically modified electrode

Abstract

Abstract An indirect voltammetric procedure for measuring free cyanide ions, using a chemically modified carbon‐paste mercury‐sensitive electrode, is described. The method is based on competitive Hg II ‐complex formation reactions between an organic ligand at the electrode surface and CN − ions in solution. A linear decrease of the peak current of mercury in a solution of a defined Hg 2+ concentration was observed, when the cyanide concentration was increased from 8.0 to 49.0 mg/L (0.3‐1.9 × 10 −6 M). The relative standard deviation for five independent measurements was 8%.