Highly efficient and automatic collection/concentration with chelating resin for inductively coupled plasma atomic emission spectroscopy

An automatically controlled collection/concentration system for ICP-AES was developed. Elements were collected with small chelating disks and chelating resin with the iminodiacetate moiety packed in a line filter. This column was installed in a 6-way valve on the pretreatment system, which could be connected on line to ICP-AES. The flow rate was 1 ml min ^-1 and conditioning of the chelating disk was carried out by flowing 0.5 M ammonium acetate (pH 5.5) for 2 min, sampling for 5 min and washing for 1 min. Elution was done by passing through 2 M HNO ₃ at 1.3 ml min ^-1 for 1 min. Bi, Cd, Co, Cr, Cu, Mn, Ni, Pb and V could be determined with 5.0 ml of the sample solution. The enrichment factors were 3∼15 times and the collection efficiencies were better than 80%. The detection limits (LOD) were from 0.003 for Mn to 0.311 for Bi, which were several 10 to 100-times lower than that of normal LOD of ICP-AES. This method was successfully applied to the determination of these metals in tap and river-water samples.