Multivariate analysis of Cd(II), In(III), Tl(I) and Pb(II) in mixtures using square wave anodic stripping voltammetry

Accurate qualitative and quantitative results were obtained by the application of parameter estimation methods. viz. Classical Least Squares 'CLS', Inverse Least Squares 'ILS' and Kalman Filter 'KF' algorithms. These methods were used to separate strongly overlapping electrochemical peaks produced by binary, ternary and quaternary mixtures of traces of cited poisonous heavy metals stripped from the hanging mercury drop electrode in an acetate-bromide electrolyte using the square wave anodic stripping voltammetry. The analysis was achieved using a single standard addition, the concentrations studied were down to 50 nM and molar ratios up to 1:6 for binary mixtures. A statistical analysis of the results was reported. The method was applied for the ultratrace analysis of the cited cations in a sample of sodium hydrogen carbonate AR. (C) 1998 Elsevier Science B.V. All rights reserved.