Solid phase extraction of nickel from environmental water samples using solid sulfur as adsorbent prior to determination by flame atomic absorption spectrometry

Heavy metals such as nickel are toxic and harmful, even at low concentrations to aquatic life, human beings and the environment [1]. Flame atomic absorption spectrometry (FAAS) has been widely used for the determination of trace metal ions. However, direct determination of metal ions at trace levels by FAAS is limited due to their low concentrations and matrix interferences. So using a preconcentration method is necessary, before determination by FAAS [2]. Solid phase extraction (SPE) is the most common technique used for preconcentration of analytes in environmental waters [3]. In SPE procedure the choice of appropriate adsorbent is a critical factor to obtain full recovery and high enrichment factor. In this research work a new method based on adsorption of nickel ions on sulfur is described for preconcentration of Ni (II) followed by flame atomic absorption spectrometric determinations. The effects of the analytical parameters including pH of the sample solution, eluting solution conditions, flow rate of sample solution, sample volume and interfering ions for the column solid phase extraction were investigated. Under the optimum experimental conditions, preconcentration factor, analytical detection limit, adsorption capacity and reusability of the sorbent were determined. The results were really excellent. The proposed method was applied for the determination of nickel in tap, river and spring water samples. The results will be presented and discussed.