Preconcentration and separation with Amberlite XAD-4 resin; determination of Cu, Fe, Pb, Ni, Cd and Bi at trace levels in waste water samples by flame atomic absorption spectrometry.

A method for the preconcentration of Cu, Fe, Pb, Ni, Cd and Bi as their diethyldithiocarbamate chelates was proposed using a column filled with Amberlite XAD-4 resin. The retained analytes on the resin were recovered with a small volume of acetone. The metal ions in the effluent were determined by a flame atomic absorption spectrometer. Different factors including pH of sample solution, sample volume, amount of XAD-4 resin, amount of ligand, eluent volume and matrix effects for preconcentration were examined. The recoveries for the analytes under the optimum working conditions were higher than 95%. The relative standard deviations of the determinations were below 9%. The limits of detection (3 s, n=20) for analytes were found to be between 4 and 23 mug l(-1). The proposed method was applied to the analysis of some waste waters from the organized industrial region of Kayseri.