Determination of cobalt (II) with 1-(2-Pyridylazo)-2-naphthol modified carbon nano tube paste electrode in electrowinning solution of Sarcheshmehcopper complex by stripping voltammetry

A method for the determination of cobalt(II) by stripping voltammetry using a carbon paste electrode constructed by incorporating 1-(2-pyridylazo)-2-naphthol(PAN) into a conventional carbon paste mixture composed of nano tube, graphite powder and Nujol oil has been developed. Several influencing factors for the determination of cobalt(II) were studied in detail and the optimum analytical conditions were found to be as follows: pH 2.5; composition of electrode, 20% and time of preconcentration 3 min. The calibration curve for cobalt(II) obtained by stripping voltammetry was linear range of 10-50 ppb. The effects of coexisting ions were also investigated to test the applicability of the proposed method to the determination of cobalt(II) in electrowinning solution of Sarcheshmeh-copper complex sampels.