Constant-current stripping analysis for iron(III) by adsorptive accumulation of its Solochrome Violet RS complex on a carbon-fibre electrode

Abstract

The optimum experimental conditions with respect to pH, adsorption potential and Solochrome Violet RS concentration for the constant-current stripping determination of iron(III) have been investigated. The suggested procedure has been used for the determination of iron(III) in tap water and the accuracy investigated both by analysing standard solutions and by comparison with results obtained by atomic-absorption spectrometry. The relative precision was 6–13% and the detection limit for iron(III), set by the reagent blank, was approximately 1 μg/l. The results obtained with a mercury-film coated carbon-fibre flow electrode have been compared with those obtained with a hanging mercury drop electrode. The advantages of measuring electrode potential vs. time instead of vs. current have been evaluated.