石墨炉原子吸收法测定空气中铅和镉

Determination of lead and cadmium in air by graphite furnace atomic absorption spectrometry

本文建立了采用微孔滤膜采集空气中铅和镉,自动石墨消解仪对滤膜样品进行前处理,石墨炉原子吸收法进行测定的方法。本实验优化了消解液的组合,使滤膜样品消解更完全,当采样体积为300L,铅、镉的最低检出质量浓度分别为0.0001、0.00001mg·m^-3,加标回收率在92.1%~103.4%之间,6次测定的相对标准偏差均小于4%。该方法具有前处理简单、污染小、检出限低、精密度和准确度较好等优点,适用于大批量环境空气中痕量铅和镉的分析。

In this paper, a method was established for the determination of lead and cadmium in the air by microporous filter film, the sample was pretreated by automatic graphite dissolver and the graphite furnace atomic absorption method. In this experiment, the composition of the solution was optimized to make the membrane sample digestion more complete. When the sample volume was 300 L, the minimum detection mass concentrations of lead and cadmium were 0.0001mg·m^-3 and 0.00001mg·m^-3, respectively. The recovery rate was 92.1% to 103.4%. The relative standard deviation of the six measurements was less than 4%. The method has the advantages of simple pretreatment, low pollution, low detection limit, good precision and accuracy, and is suitable for the analysis of trace lead and cadmium in large quantities of air.