同位镀铋膜电极测定水样中铅和镉离子的研究

The study on the determination of lead and cadmium ions in water sample with situ preparing-bismuth film electrode

采用阳极溶出伏安法,以铋膜电极替代汞膜电极测定水样中痕量铅和镉离子。考察并优化了同位镀铋膜测定铅、镉的条件。实验结果表明:铅和镉在铋膜电极上可得到灵敏的溶出峰,峰高和溶出电位与汞膜电极法相近,使用铋膜电极可避免使用汞膜电极带来的环境污染。当电沉积时间为5min时,铅和镉的检出限分别达1.0×10-7mol/L和5.0×10-8mol/L。同时,由于每次溶出后可方便地将铋膜溶解更新,因此,能保证各次测定的重现性。

In this paper, bismuth film electrode is used to replace mercury film electrode in the determination of trace lead and cadmium ions using anodic stripping vohammetry. The experiment conditions which influence the determination of Pb2＋ and Cd2＋ via situ plating bismuth - film electrode were investigated and optimized. Experimental results show that sensitive stripping peak of lead and cadmium can be obtained in the bismuth film electrode with similar strip peak potential to mercury - film electrode. Using bismuth film electrode can avoid environmental pollution caused by mercury electrode. When enrichment time is 5 min, the detection limit of Cd2＋ and Pb2＋ are 1.0 ×10^-7moL/L and 5.0 ×10^-8mol/L respectively