Solid phase extraction method for the determination of Cd2+, Pb2+ and Cu2+in different water samples by flame atomic absorption spectrometry using green modified groundnut shells

A novel modified biomass (GNS) has successfully been utilized as a new solid phase extraction (SPE) sorbent for the determination and preconcentration of cadmium, lead and copper in aqueous medium. The batch procedure shows the maximum extraction percentage on the GNS modified with sodium carbonate (SC-GNS) are 100, 98 and 96% for Cd2+, Pb2+ and Cu2+ions, respectively, at the optimal conditions pH 4-6 and 30 min shaking time .The column procedure shows that the optimal conditions were at sample flow rate 4 mL.min-1 and desorption by 10 mL from 1.0 mol L-1 hydrochloric acid. The breakthrough volume was greater than 2000 ml with preconcentration factor 200 for all studied metal ions .The limit of detection was found to be 0.28 ,0.48 and 1.2 for Cd2+, Pb2+ and Cu2+ions, respectively. Precision (R.S.D %)of the metal ions extraction was found to be less than 5 %( n=3). The developed method was successfully applied for determination of these metal ions in different water samples (tap water, intake of water treatment plant and Qaroun lake at Fayoum city, Egypt) by flame atomic absorption spectrometry (FAAS).