Determination of trace bismuth in urine and tap water samples by atomic absorption spectrometry after solid-phase extraction

摘要

In this paper,a new method for the determination of bismuth in urine and tap water is described.The methodology combines determined using a hydride generation-atomic absorption spectrometry (HG-AAS) with pre-concentration of the bismuth on the modified organobentonite by dithizone (D-O-bentonite).Optimal experimental conditions for the adsorption and elution of the bismuth,including pH,contact time,eluent concentration,eluent volume and co-existing ions have been investigated.The result showed that the bismuth ion could be adsorbed on the D-O-bentonite.The adsorbed quantitive was affected by the pH value and contact time.In the medium ofpH 5.0,the shaking time was 10 min,the adsorption capacity was 15.2 mgg-1.The bismuth adsorbed on the modified organobentonite by dithizone could be completely eluated by using 2 mol.L-1 HNO3.The method has been applied to the pre-concentration/separation of bismuth in the human urine and tap water samples with satisfied results.