用二安替比林苯乙烯基甲烷光度法测定碳钢及低合金钢中锰

Spectrophotometric Determination of Manganese in Carbon-steel and Low-alloy Steel With Diantipyrylvinylphenylmethane

本文研究了二安替比林苯乙烯基甲烷(DAVPM)与 Mn(Ⅳ)的反应条件;在碱性介质中利用氧将 Mn(Ⅱ)氧化至 Mn(Ⅳ),然后在磷酸介质中 Mn(Ⅳ)将 DAVPM 氧化成红色产物,其最大吸收峰在544nm 波长处。锰量在0～30μg/25ml 范围内符合比耳定律。用于碳钢及低合金钢中锰的测定能获得满意结果。

The reaction conditions of diantipyrylvinylphenylmethane(DAVPM)with Mn(Ⅳ) are studied.In the alkaline medium,Mn(Ⅱ)is oxidized to Mn(Ⅳ)by oxygen,and then in H_3PO_4 medium,DAVPM can be oxidized by Mn(Ⅳ)to form a red product,having an absorption maximum at 544 nm with a molar absorptivity of 9.13×10~4 L.mol^(-1)·cm^(-1) (in the absence of iron)and 4.83×10~4 L.mo1^(-1)·cm^(-1)(in the presence of iron),respecti- vely.Beer's law is obeyed for 0～30μg Mn/25ml.Large amounts of iron and most of metal ions do not interfere with determination.The method has been used to determine manganese in carbon-steel and low-alloy steel with satisfactory results.