An electrochemical technique is presented to simultaneously determine the concentrations of Fe(II) and Fe(III) ions using a rotating disk electrode. The method consists of using a steady state polarization technique where the developed limiting currents are measured and related to the concentration of the cations present in solution. Two linear equations were derived which correlate the limiting currents with the concentrations of the pair cations. The equations are used to easily and simultaneously determine the concentrations of the multivalent species. The precision and accuracy of the technique were found to be comparable to other advanced methods for the quantification of cations, such as capillary zone electrophoresis and spectro-photometric sequential injection analysis.
- Rotating disk electrode