溶出伏安法同时测定矿山地下水中痕量砷铅

Simultaneous Determination of Trace Arsenic and Lead by Stripping Voltammetry in Groundwater of Mines

本文以电化学预处理的金电极为工作电极,采用线性扫描溶出伏安法实现了矿山地下水中痕量As3+、Pb2+的同时测定。研究了金电极的预处理方法、不同预富集时间和不同电解质对重金属离子测定的影响规律。研究发现,电化学预处理有利于金电极对重金属离子的响应,在最优实验条件下,As3+、Pb2+在电化学活化的金电极上分别于0.18V、-0.07V产生灵敏的溶出峰,峰高与其浓度线性相关,检测限分别可达到0.5!g/L、2!g/L。该方法操作简单、干扰小、线性范围宽、灵敏度高。

The trace As3＋ and Pb2＋ in groundwater of mines in Lengshuijiang were simultaneously determined by using the gold electrode as the working electrode. The influences of the working electrode,pre-deposition time and supporting electrolytes on the determination of heavy metal ions were investigated. It was found that the electrochemically pretreated gold was more appropriate for the simultaneous determination of As and Pb than the mechanically treated gold electrode. Under the optimum condition, the peak potentials were 0. 18 V for As3＋ and -0. 07 V for Pbz＋ at the gold electrode. The peak currents changed linearly with the concentrations of As3＋ and Pbz＋ and the detection limits were 0. 5 μg/L and 2 μg/L, respectively. This proposed method had the advantages of simple operation, minimum interference, wide linear range and high sensitivity.