FRESENIUS ENVIRONMENTAL BULLETIN, vol.17, no.4, pp.467-477, 2008 (SCI-Expanded)
The adsorption and preconcentration studies of Cu(II), Pb(II) and Cd(II) were investigated on Procion Red MX-3B attached poly(ethylene glycol dimethacrylate-hydroxyethyl methacrylate) [poly(EGDMA-HEMA)] microbeads. The effects of various experimental parameters were investigated using a batch and column technique. The adsorption data followed Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms, but the Langmuir model is better to represent the adsorption process. Procion Red MX-3B- poly(EGDMA-HEMA) microbeads were used as packing material for the minicolumn in an on-line preconcentration system for Cu(II), Pb(II) and Cd(II) determination. Metal ions were sorbed in the minicolumn, from which it could be eluted directly to the nebulizer-burner system of the flame atomic absorption spectrometer (FAAS). Elution of all metal ions from minicolumn can be made with 0.2 mol L-1 HNO3. For a preconcentration time of 2 min, the preconcentration factors were 51, 55 and 48, and the detection limits 1.25, 0.5 and 10 mu g L-1, for Cu(II), Cd(II) and Pb(II), respectively. When using 10 min preconcentration time for Pb(II), the preconcentration factor and detection limit were found to be 273 and 1.1 mu g L-1, respectively. The influence of diverse ions on the microbeads performance was also investioated. The accuracy of the method was tested by analyzing certified reference water (SPS-SW2- Surface Water and LGC 6010 - Hard Drinking Water) and spiked tap water samples. These results proved that the procedure can be applied satisfactorily for lead, copper and cadmium determination in water samples.