铅(Ⅱ)-Tiron络合物极谱吸附波研究

A Study on the Polarographic Adsorption Wave of Lead(Ⅱ)-Tiron

在0.56mol/L NaAc—0.04%Tiron 溶液中,铅(Ⅱ)与 Tiron 产生的络合物,在单扫描示波仪上可观察到一灵敏的极谱导数波,其峰电位为-0.49V(vs.SCE),峰电流与铅浓度在7.7×10^(-6)—6.8×10^(-6)mol/L 范围内成线性关系,检测限为3.8×10^(-(?))mol/L.应用该波测定了铜合金中的微量铅,结果良好,精密度和准确度均较满意,本文研究了形成铅-Tiron 络合物吸附波的条件,探讨了波的性质,用极谱法测定出其络合比为1:1.

In the solution of 0.56 mol/L NaAc-0.04% Tiron,lead(II)=Tiron complex shows a sen- sitive adsorption wave as observed by single sweep polarography.This derivative wave shows a peak po- tential at-0.49V(vs.SCE).Its peak current bears a linear relationship with the concentration of Pb (II)in the range of 7.7×10^(-8)-6.8×10^(-6) mol/L.The limit of detection for Pb(II) lies in 3.8× 10^(-8) mol/L.The application of this wave to the determination of trace Pb color alloy has yieded re- suits with fairly satisfactory precision in and accuracy.Various conditions underlying the formation of adsorption wave of Pb(II)-Tiron complex are studied and its properties are discussed.The complexa- tion ratio is determined to be 1:1.