Determination of trace impurities in cadmium compounds by flame atomic absorption spectrometry after solid phase extraction

An enrichment/separation system was developed for the determinations of Cu (II), Fe(III) and Pb(II) impurities in cadmium salts by flame atomic absorption spectrometry (FAAS). The procedure is based on the adsorption of analyte ions on Chromotrope 2R coated Amberlite XAD-1180 resin. The effects of some analytical parameters including pH of the sample solution and its volume, effects of cadmium matrix, and flow rates of sample and eluent solutions were investigated. Under optimized conditions, the relative standard deviation of the combined method of sample treatment, preconcentration and determination with FAAS (n=7) is generally lower than 10%. The limit of detection (3σ) was between 0.024-0.20 mg/l. The method was applied to the separation and preconcentration of three trace elements in cadmium salt solutions