APPLICATION OF AN ONLINE PRECONCENTRATION SYSTEM IN SIMULTANEOUS ICP-AES

A PC-controlled on-line preconcentration system (TRACECON) developed by Knapp et al. [11], was connected to a JY-70 Plus simultaneous ICP spectrometer to preconcentrate on-line seven trace elements (Cu, Fe, Zn, Cr, Ni, Mn, V) in biological and environmental samples. EDTrA-cellulose was used as column material. The elemental concentrations were determined by simultaneous ICP-AES. The effect of pH of the sample solution on the enrichment was studied. It was found that the recoveries of chromium and iron depend strongly on the pH of the sample solution. All the elements mentioned were recovered quantitatively at pH 4.0 +/- 0.1. The flow rates of sample solution and element solution were optimized. The enrichment factors for seven elements at 5 ml loading volume range from 3.9 for Cu to 7.9 for Zn. The detection limits of all seven elements were improved. The accuracy of the method was tested by the analysis of a number of CRMs of NIST, BCR and NIES. Most results are in good agreement with the certified values.