Comparison of novel sorbents for preconcentration of metal ions prior to their flame atomic absorption spectrometry determination

In the present study, the efficiency and usability of two sorbents including silver nanoparticles loaded on activated carbon and homemade activated carbon for removal and recoveries of heavy metal ions by solid-phase extractant were investigated. These materials characterization was carried out using different techniques such as SEM, XRD, BET and UV-vis. The analytes such as Zn2+, Cu2+ and Pb2+ ions was enriched onto sorbent and subsequent eluted and determined by flame atomic absorption spectroscopy. The influences of the analytical parameters including pH, type and condition of eluent, adsorption capacities and amount of adsorbent, condition of eluent and sample volume on the metal ions recoveries were optimized. The optimum pH value for the separation of metal ions on these new sorbents was 4. The adsorbed metal ions could be completely eluted by using 10.0 mL 4.0 mol L-1 HNO3 solution. The loading of 30 mg of ligand onto 0.6 and 0.1 g of AC and Ag-NP-AC, respectively, make possible quantitative sorption of analytes. The accurate and easy determination of analytes in the presence of high limit of matrices constituent is possible without generation of significant problems. The applicability and accuracy of method were tested by its application for analytes quantification in complicated matrices with recoveries more than 91% and relative standard deviation lower than 5%. (C) 2013 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.