Separation and preconcentration system for lead and cadmium determination in natural samples using 2-aminoacetylthiophenol modified polyurethane foam

A new modified polyurethane foam using 2-aminoacetylthiophenol (AATP) was employed for selective separation, preconcentration and determination of Cd and Pb ions in different samples by flame atomic absorption spectrometry (FAAS). This new modified foam was used as an effective sorbent for the solid-phase extraction (SPE) of Cd and Pb ions from aqueous solutions from natural samples. Experimental conditions for effective separation of trace levels of the analyte ions were optimized with respect to different experimental parameters in batch process. The preconcentration factors are 167 and 250 for Pb and Cd respectively. The relative standard deviation (R.S.D.) under optimum conditions is <10% (n=5). The accuracy of the method was estimated by using a reference material BDH Cat no: 456422W real samples that were spiked with the analyte ions. The extraction isotherm of both Cd and Pb ions was obtained. This study indicated that the novel foam presents a high affinity for Cd and Pb due to the presence of good extractive sites (S, N and O) which are introduced to the foam material. The bonding of the studied metal ions by the foam is useful for the removal of metal contamination from real samples. (C) 2009 Elsevier B.V. All rights reserved.