On-line preconcentration and determination of vanadium in tap and river water samples by flow injection-inductively coupled plasma-optical emission spectrometry (FI-ICP-OES)

A flow injection system coupled to an inductively coupled plasma optical emission spectrometer (ICP-OES) was used for the on-line preconcentration and subsequent determination of vanadium. Trace amounts of V were preconcentrated by sorption on a conical minicolumn packed with immobilised yeast cells in the absence of complexing reagent at pH 7.0. Vanadium was removed from the minicolumn with a 50% HCl solution. An enrichment factor of 45-fold for a sample volume of 10 ml was obtained. The detection limit (LoD) for the preconcentration method proposed was 0.06 μg l−1. The precision for 10 replicate determinations at the 5 μg l−1 V level was 3.4% relative standard deviation (RSD), calculated from the peak heights obtained. The calibration graph of the preconcentration method for V was linear with a correlation coefficient of 0.9997 at levels near the detection limits up to at least 100 μg l−1. The method was successfully applied to the determination of V in tap and river water samples.