Flame atomic absorption spectrometric determination of trace amounts of silver in aqueous sample after solid phase extraction using octadecyl silica membrane disks modified by 2-[(2-mercapt ophenyliminio)methyl]phenol

A rapid, Sensitive and selective method for separation and preconcentration of silver from aqueous media using octadecyl silica membrane disks modified by 2[(2-mercaptophenylimino) methyl] phenol and atomic absorption spectrometry has been developed. The influence of pH, flow rates of sample and eluent, amount of ligand, nature and amount of stripping reagent were evaluated. The maximum capacity of the membrane disk modified by 6 mg of the ligand was found to be 220 mu g of Ag+. The relative standard deviation for seven replicate measurement of 2.5 mu g of silver from 1000 mL samples was 2.4%. The breakthrough volume for 5 mu g silver is 2000 mL. The limit of detection of the proposed method was 8 ng of Ag+ per 1000 mL. The analytical procedure was successfully applied to the determination of silver in water and waste water samples and accuracy was examined by recovery experiments and independent analysis by graphite furnace atomic absorption spectrometry (GFAAS).