Determination of Gold by Flame Atomic Absorption Spectrometry with Solid Phase Extraction

To prepare the SPE column,ether solution of 5-thio-15-crown-5 (5-T-15-CR-5) was first mixed with porous graphitized carbon black,and the solvent ether was removed by evaporation.The dried mixture was then filled into a PTFE column which was rinsed successively with 0.1 mol·L-1 Na2S2O3 solution and acetate buffer solution of pH 3.5,and was ready for enrichment of auric ion.Gold(Ⅲ) in sample solution of acetate buffer medium of pH 3.5 was enriched on the SPE column and eluted from the column by reverse elution with definite amount of 0.1 mol·L-1 Na2S2O3 solution and the eluate obtained was used for FAAS determination.The proposed method was applied to the determination of gold in samples of environmental water and ores,giving results in consistency with the results obtained by ICP-MS method.Values of RSD′s (n=5) were in the range of 2.4%-3.4% and results of recovery were in range of 92.6%-97.8%.