Analytical Sciences

Abstract − Analytical Sciences, 17(5), 609 (2001).

Differential Pulse Adsorption Stripping Voltammetric Determination of Copper(II) with 2-Mercaptobenzimidazol at a Hanging Mercury-Drop Electrode
Ali Asghar ENSAFI,*  Sharyar ABBASI,* Hassan RAHIMI MANSOUR,* and Iraje MOHAMMADPOUR BALTORK**
*College of Chemistry, Isfahan University of Technology, Isfahan, 84154, Iran
**Department of Chemistry, Isfahan University, Isfahan, Iran
Copper(II) was selectively accumulated on a hanging mercury-drop electrode by using 2-mercaptobenzimidazole. Ensuing measurements were carried out by differential pulse adsorption stripping voltammetry. Factors affecting the accumulation, reduction, and stripping steps were investigated and a procedure was developed. The optimum conditions for the analysis of copper were pH 5.0, 5.33 x 10-5 M 2-mercaptobenzimidazole and an accumulation potential of -0.10 V (vs. Ag/AgCl). A linear range was obtained in the concentration range 0.2 - 100 ng/ml with a 90 s accumulation time and a scan rate of 16 mV/s. For ten successive determinations of 1.0, 20.0 and 70.0 ng/ml copper(II), relative standard deviations of 4.2, 3.5 and 2.8%, respectively, were obtained. The developed method was applied to the determination of copper in commercial salts and aluminium alloys.