Comparison of two kinetic approaches for copper speciation using ion-exchange columns and ion-exchange modified carbon paste electrodes

Abstract

A comparison of speciation data for copper by using an anodic stripping voltammetric procedure on a chemically modified electrode and an ion-exchange column procedure was made. An Amberlite IRC-718 resin was employed in both the methods. In the ion-exchange column method, the time scale of the measurement was varied between 0.2 and 150 s, in order to obtain kinetic information. The measurement time in the chemically modified electrode procedure was evaluated and remained constant. Both the procedures were used to investigate model complexes of copper and natural water samples. For similar measurement times, similar metal availability was observed for both, the electrochemical and chromatographic approaches. Better kinetic information can be obtained with an ion-exchange column procedure when metal ion is present in the sample as several complexed forms.