杂多酸体系极谱波测定钢中微量磷

Determination of Microamounts of Phosphorus in Steel by the Use of Polarographic Wave of Heteropoly Acid

在０．１３ｍｏ１／ＬＮ＿２ＳＯ＿４及８％丙酮介质中，ｐ（Ⅴ）－Ｓｂ（Ⅲ）－Ｗ（Ⅵ）三元杂多酸在示波极谱仪上产生一良好的吸附还原波。峰电位为一０．５２Ｖ（υｓ．ＳＣＥ），峰电流（导数波高）与Ｐ浓度在８．０×１０￣（－７）～２．０×１０￣（－５）ｍｏｌ／Ｌ范围内呈线性关系，检测下限为２．０×１０￣（－７）ｍｏｌ／Ｌ。对极谱波的性质进行了探讨，用该法测定了钢标样中的微量Ｐ，结果与推荐值相符。

he phosphorus(Ⅴ)-antimony(Ⅲ)-tungstate(Ⅵ)ternary heteropoly acid complex produces a sensitive adsorption wave on a single sweep oscillopolarograph in 0.13mol/L N_2SO_4 -8%acetone solution. The peak potential of the wave is 0.52V(υs.SCE).Alinear relationshipholds hetween the peak current and the phosphorus concentration ranging from 8.0× 10￣(-7)～2.0×10￣(-5)mol/L. The limit of detection is 2.0× 10￣(-7)mol/L. The polarographic behavior is discussed.This method has been applied to the determination of microamounts of phosphorus insteel and the restults were sartisfactory.