Determination by AAS of some trace heavy metal ions in some natural and biological samples after their preconcentration using newly chemically modified chloromethylated polystyrene-PAN ion-exchanger

The use of chemically modified chloromethylated polystyrene-PAN, CMPS-PAN ion-exchanger for the separation of Au(III), Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), Pd(II) and Zn(II) from aqueous solution is described. After preconcentration, the heavy cations under investigation were determined using atomic absorption spectrometry (AAS). The distribution coefficient, K-d and the percentage concentration of the studied metal ions on the ion-exchanger at equilibrium, C-M,C-eqm, % are evaluated as a function of pH, mass of ion-exchanger and shaking time. The calculated K-d values for the investigated cations are in the range of 25 - 7.9 x 10(5) cm(3) g(-1). The interfering effects of different foreign ions were studied. The chelates formed between CMPS-PAN ion-exchanger and the investigated metal ions were characterized by FT-IR spectrometry, potentiometry and thermal analysis. The present method is simple and rapidly applicable for the microdetermination of eleven heavy metal ions at ppb levels. Analytical applications for the preconcentration and separation using the modified CMPS-PAN ion-exchanger and the determination of the studied metal ions in tap, Nile, waste and sea water samples, human urine, milk (synthetic and natural) and some ores were carried out.