用镉离子电极电位滴定法测定镉、钙、镁

Determination of Cadmium, Calcium and Magnisium Ions by Potentiometric Titration with Cadium Ion-selective Electrode

镉、钙、镁三种离子的混合物可根据它们与EDTA,EGTA所形成配位物稳定常数的不同,利用镉离子选择电极作指示,电位滴定法分别测定其含量。本文研究了三种组份测定的适宜条件,并对废水废液进行了测定,与常用方法相比较,结果一致。镉、钙、镁离子浓度在1.0×10^(-1)～1.0×10^(-4)M范围内均适用,相对误差≤±0.8%,变异系数≤0.9%。

Cadmium, calcium ana magnesium in mixture were determined by potentiometric titratonwith a cadmium ion-selective electrode, based on the difference in the formation constants ofthe complex which are formed by these ions with disodium ethylenediaminetetraacetate andglycoletherdiaminotetraacetic acid. And samples from waste water were analyzed with his metho-d achieveing results with relative error less than ±0. 8% and relative standard devaton less than0.9%, when concentrations of cadmium, calcium and magnisium are at the level of 1.0×10^(-1)1.0×10^(-4).