Application of Sulfur Nanoparticles as a Solid Phase Extraction Sorbent for the Preconcentration of Lead(II) and Palladium(II) in Environmental Samples Prior to Flame Atomic Absorption Spectrometry Determination

The application of sulfur nanoparticles as an efficient adsorbent for the solid-phase extraction and determination of the trace amounts of Pb and Pd ions was investigated in environmental samples using flame atomic absorption spectrometry. 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 were investigated and optimized. The results showed that the optimal conditions for quantitative recovery of the metal ions by adsorption and elution on the sulfur nanoparticles were achieved by employing a flow rate of 2 ml min-1, a pH of 9.5 for the sample solutions, and an eluent composed of 4.0 M HNO3 in ethanol. The maximum adsorption capacity of SNPs as sorbents at optimum conditions for lead and palladium ions was found to be 2.80 mg g-1 and 2.87 mg g-1, respectively. At optimum conditions, the detection limits of this method were 0.3 and 2.5 ng ml-1 for Pb(II) and Pd(II), respectively. The proposed procedure was applied to the determination of the metal ions in soil and water samples.