水中痕量铅的氢化物原子荧光测定

提出了以酸性重铬酸钾碱性铁氰化钾为氧化剂的铅氢化物发生体系 .采用断续流动氢化物发生器 ,对原子荧光法测定痕量铅的条件进行了系统研究 .以 2 0g/L柠檬酸钠为干扰抑制剂 ,考察了共存元素的干扰情况 .在最佳测试条件下 ,测得铅的检出限 ( 3σ)为 0 .2 1μg/L ,相对标准偏差 ( ρ(Pb) =2 5μg/L ,n =11)为 1.2 % .对水中痕量铅进行分析 ,回收率为 97.5%～ 10 5.0 % ,结果令人满意 .

Determination of Trace Lead in Water by Hydride Generation Atomic Fluorescence Spectrometry

A method was proposed for hydride generation of lead using potassium dichromate in acid solution and potassium ferriccyanide in alkaline solution as oxidant. The conditions for determination of trace lead by atomic fluorescence spectrometry with a intermittent hydride generator were studied systematically. Effects of some coexisting elements on the determination of lead were investigated. Citrate was used to eliminate the interferences. Under the optimum conditions, the detection limit and RSD of the method based on eleven determinations of 25 μg/L Pb were 0.21 μg/L and 1.2% respectively. The method was applied to the analysis of water for lead contents, and satisfactory results were obtained.