Solid phase extraction of lead and cadmium using solid sulfur as a new metal extractor prior to determination by flame atomic absorption spectrometry

A new method using a mini-column packed with sulfur as a new solid phase extractor has been developed for simultaneous preconcentration of lead and cadmium in water samples prior to flame atomic absorption spectrometric determinations. The effects of various parameters such as pH, flow rate of sample and eluent, type and concentration of eluent, sample volume, amount of adsorbent and interfering ions have been studied. The calibration graph was linear in the range of 10-300 and 1-20 ng mL−1 for lead and cadmium, respectively. The limit of detection based on three times the standard deviation of the blank (3Sb) was 3.2 and 0.2 ng mL−1 (n = 10) for lead and cadmium, respectively. A preconcentration factor of 250 was achieved in this method. The proposed procedure was applied to the determination of metal ions in tap, river and wastewater samples.