Column solid-phase extraction of nickel and silver in environmental samples prior to their flame atomic absorption spectrometric determinations

摘要

A biosorption procedure for preconcentration-separation of nickel(Ⅱ) and silver(Ⅰ) at trace levels on Bacillus sphaericus-loaded Chromosorb 106 (BSLC106) has been presented in this work. The conditions like pH, amounts of microorganism, eluent type, etc. for the quantitative adsorption of the analyte ions on BSCl106 column were investigated. The analyte ions were quantitatively recovered and desorbed at pH range of 6.0-7.0 and 10 mL of 1 M HCl, respectively. The effects of various cationic and anionic interferences on the recoveries of nickel(Ⅱ) and silver(Ⅰ) were studied. The detection limits for nickel(Ⅱ) and silver(Ⅰ) are 1.42 and 1.05 μg L~(-1), respectively. The accuracy of the developed procedure was tested by analyzing NISI SRM 2711 Montana soil and GBW 07310 Stream sediment certified reference materials. The proposed enrichment-separation procedure was successfully applied to the determination of analytes in natural water, black tea, tobacco, soil and sediment samples with satisfactory results.