AN OPTIMIZED ONLINE PRECONCENTRATION SYSTEM FOR ANALYSIS OF TRACE GOLD IN ORE SAMPLES

A flow injection on-line preconcentration technique, combined with graphite furnace atomic absorption spectrometry for the determination of gold in ore samples has been presented. An alpha-amino pyridine resin (AP) was loaded onto a microcolumn as the preconcentration reagent and a solution of 90% acetone-5% HCl-5% H2O was used for the gold elution. The Scaled Simplex Method was employed to optimize the flow injection manifold. The selected factors were optimized by the simultaneous consideration of two responses, absorbance and column retention efficiency, with only 12 tests. A detection limit of 0.065 mu g Au/l (3 sigma) with a relative standard deviation of 4.3%, was achieved. Ore samples containing gold have been analysed successfully using the proposed method.