Voltammetric determination of macrocomponents in etching electrolytes based on FeCl3

The possibility of direct voltammetric determination of copper, total iron and iron (III) on mechanically renewable graphite electrode has been investigated. It was shown, that the reduction of copper from chloride solutions proceeds in two stages. For copper determination a peak was used which corresponds to the reaction of Cu¹⁺ → Cu⁰ reduction. The concentration of total iron and iron (III) were determined recording the peaks at different scan parameters. The concentration of iron (II) was calculated from the difference. A procedure was been developed for voltammetric determination of copper, total iron and iron (III). The relative standard deviation of obtained results does not exceed the value 0.05. The correctness of the procedure was tested by means of "introduced-found" determination.