Chiang Mai Journal of Science

A new solid phase extraction (SPE) procedure was developed for the pre-concentration of Au(III) ions in aqueous system prior to its determination by flame atomic absorption spectrometry (FAAS). For this purpose, freshly precipitated metal-piperazinedithiocarbamates (Mn(PDTC), Zn(PDTC), Cd(PDTC), Fe2(PDTC)3, Co(PDTC), Cu(PDTC), Ni(PDTC), Pb(PDTC), Hg(PDTC) and Au2(PDTC)3) were synthesized and they have been tested for the extraction of their metal ions in aqueous solution. The freshly precipitated Cu(PDTC) was selected for the pre-concentration of Au(III) in aqueous system and the optimum experimental conditions for the quantitative sorption of Au(III) such as pH, effect of aqueous phase volume, effect of extraction period and the effect of diverse ions on the sorption of Au(III) have been investigated. The linearly range (0.5-5 mg L-1), regression equation (y = 0.0141X - 0.0005), correlation coefficient (r2= 0.9982), detection limit (3.6 mg L-1) and determination limit (11.3 mg L-1) in final Au(III) solution were obtained. The proposed method has been applied for the determination of Au(III) in some real samples.