电化学分析在环境监测中的应用研究(Ⅰ)示波极谱——Oxine滴定法测定工业废水中S^(2-)含量

DETERMINATION OF SULFIDE INDUSTRIAL WASTE WATER BY OSCILLOPOLARO-GRAPHY-OXINE TITRATION

研究了在 HAc-Na Ac-KCl介质 (p H=5 .5 )中用 Cu2 +离子沉淀 S2 -离子 ,过量的 Cu2 +离子用标准 8-羟基喹啉溶液返滴 ,并以 8-羟基喹啉在微铂电极交流示波极谱图上出现的敏锐切口指示滴定终点。废水的色度和浊度均不影响测定 ,试样勿需预蒸馏、分离吸收等繁杂的操作手续 ,方法简便、快速、准确 ,标准偏差小于 0 .0 5 0 ,变异系数小于0 .60 % ,回收率为 98～ 1 0 2 %。

In the paper, determination of sulfide in industrial waste water by oscillopolarography oxine titration is studied. In acetic acidsodium acetate potassium choride base solution at pH5.5, S 2- can be precipitated with standard solution of Cu 2+ and the excess Cu 2+ is back titrated with standard solution of oxine. Oxine gives sharp incission in the cell with one Pt microelectrode, which can be used to indicate the end point. Their determining conditions and the effects of other substance have also been studied. In the paper, the colour and turbidity of the sample are ignored, and the sample needs no predistillation. The method is simple, fast and accurate. The standard deviation and variation coeffitient are below 0.050 and 0.60% , respectively, The recovery is 98%～102%.