TURKISH JOURNAL OF CHEMISTRY, vol.31, no.6, pp.631-646, 2007 (SCI-Expanded)
The use of chemically modified XAD-4-1,2-bis (o-aminophenylthio) ethane chelating resin for pre-concentrating Cr6+, Mn2+, Fe3+, Co2+, Cu2+, Cd2+, Zn2+, Pb2+, and Ni2+ was studied using flame atomic absorption spectrometry (FAAS) for metal monitoring in environmental samples. Cd2+, Zn2+, Pb2+, and Ni2+ ions were quantitatively recovered at the rate of 96.0%, 101.0%, 101.0%, and 95.0%, respectively (RSD < 5%), from the studied solutions. The procedure is based on the retention of analytes on a short column of 1,2-bis (o-aminophenylthio) ethane-XAD-4 chelating resin from a buffered sample solution and subsequent elution with 1 M HNO3. Various parameters, such as pH, eluent type, and concentration, flow rate of sample solution and matrix interference effect on the retention oft he metal ions have been studied. The optimum pH for the sorption of the above-mentioned metal ions was about 6. The adsorption and batch capacity of adsorbent and loading half time ( t(1/2)) for Ni2+, Zn2+, Cd2+, and Pb2+ were established. The limit of detection was 3.0 mu g L-1 for Pb2+ and Ni2+, 0.6 mu g L-1 for Cd2+, and 0.3 mu g L-1 for Zn2+. The validation of the procedure was carried out by analysis of certified reference materials and standard addition. The proposed enrichment method was applied to environmental samples from Trabzon.