流动注射在线罗丹宁纤维预浓集快速测定地质样品中痕量金

Flow Injection On-Line Preconcentration with Rhodanine Chelating Fibre for the Determination of Trace Gold in Geological Samples by Flame AAS

应用流动注射在线罗丹宁纤维预浓集火焰原子吸收法快速测定地质样品中痕量金。选用微型细柱,内装有新型螯合罗丹宁纤维,在20％王水介质中,样品流速为7.9ml/min,上柱40s;用0.025％硫脲就可洗脱,洗脱液流速为2.6ml/min,分析速度为60N/h,浓集倍数(EF)为25(浓集效率为25EF/min)。对于0.20μg/ml Au测定21次,RSD为1.9％,方法检出限(3σ)为0.001μg/mlAu。用本法可以分析Au含量在0.02～20g/t的地质样品。

A flow injection on-line concentration method for the determination of gold in geological samples by flame atomic absorption spectrometry is reported in this paper. A mini-column packed with a new type of chelating fibre-rhodanine fibre was used for the concentration. The sample solution adjusted to an acidity of 20% aqua regia was passed through the column at a flow rate of 7. 9ml/min. The enrichment time was 40s. Gold on the column can easily be eluted with thiourea at a flow rate of 2. 6ml/min. 60 samples can be analysed in one hour. The enrichment factor is 25 and the RSD of the determination is 1. 9%(0. 2μg/ml Au,n = 21). The proposed method can be used for the determination of gold with a content of 0, 02~20g/t.