Determination of Trivalent Aluminum and Divalent Zinc in Drinking Waters by Differential Pulse Stripping Voltammetry

A Sensitive and precise differential- pulse stripping voltammetric method at static mercury dropping electrode (SMDE) has been applied to measure zinc(II) by anodic stripping at pH~¼4 and aluminum(III) by adsorptive cathodic stripping mode in presence of 1&Cross10^-3M N,N` -bis-2-hydroxyethyl-2-amino-ethane sulphonic acid (BES) buffer at pH~7.1 and 2⨯10^-5 M of alizarin red S as a ligand in drinking water samples purchased in Egypt. The optimal preconcentration potentials and times for the detection of these metal ions in all samples have been studied. The concentrations of metal ions were determined by standard addition method. The statistical parameters i.e. standard deviation, correlation coefficient, slope and confidence have been calculated. The limits of detection for Zn and Al were 2.5 and 10 µg l^-1, respectively.