Voltammetric Determination of Arsenic in Zinc Oxide Used as a Feed Additive

Abstract

Cathodic stripping voltammetry at a hanging mercury drop electrode was applied for determination of arsenic in samples of zinc oxide intended for use as a feed additive. The determinations were carried out in acidic medium in the presence of Cu(II). The As(V) was prereduced to As(III) by potassium iodide and ascorbic acid at ambient temperature. The detection limit was 0.1 ng mL−1. The feasibility of simultaneous determination of arsenic and cadmium in such analysis was also shown. The electrothermal atomic absorption spectrometry was used as a reference method.