A simple in situ preconcentration for the simultaneous determination of arsenic(III) and arsenic(V) in environmental water samples based on solid-phase extraction

Abstract

A simple in situ preconcentration method using solid-phase extraction for the simultaneous determination of arsenic(III) (arsenite)and arsenic(V) (arsenate) in environmental water samples has been developed, followed by hydride generation-atomic absorption spectrometry. This method is based on the simultaneous collection of arsenic(III) and arsenic(V) and their successive elution from a small column packed with a zirconium-loaded sorbent. A water sample was taken into a graduated syringe to prevent the oxidation of arsenic(III) to arsenic(V) by air. The water sample (pH 4.5) was passed through a small column to collect arsenic(III) and arsenic(V) onto it. The retained arsenic(III) and arsenic(V) were quantitatively eluted with 0.5 mol/l hydrochloric acid and then a 0.5 mol/l sodium hydoxide solution, respectively. The proposed method is applicable to brackish and sea-water samples as well as fresh-water samples.