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...