FLOW-INJECTION PRECONCENTRATION OF GOLD (III) ON CELLEX-T FOR DETERMINATION BY FLAME ATOMIC-ABSORPTION SPECTROMETRY

Gold was determined by flame atomic absorption spectrometry following on-line preconcentration on a functionalized cellulose sorbent, Cellex T, in a flow injection system. Thiourea was used to elute the sorbed gold into the nebulizer. Optimization studies of sample loading rate, elution rate and sample acidity were carried out. The presence of platinum ions in the preconcentrated sample does not affect the gold signals monitored by more than +/- 5%. The detection limit of the proposed method was 2.2 mug l-1 and precision, measured as relative standard deviation at a level of 20 mug l-1 of gold was 2.6%. The method was validated by analysing geochemical reference samples.