一种Cr(Ⅵ)的新显色反应及其在环境水样分析中的应用

A New Colour Reaction of Chromium(Ⅵ) and Its Analytical Application in Environmental Water

合成了超高灵敏显色剂二安替比林对乙氧基苯基甲烷（ＤＡｐＥＭ），在磷酸介质中，Ｍｎ（Ⅱ）存在下，ＤＡｐＥＭ与Ｃｒ（Ⅵ）生成黄色产物，λｍａｘ＝４５０ｎｍ，ε＝１．３６×１０６Ｌ（ｍｏｌｃｍ）－１．铬（Ⅵ）含量在２—３２μｇ／Ｌ内符合比尔定律，用于环境水样中Ｃｒ（Ⅵ）的测定，结果满意．

Diantipyryl (p ethoxy) phenylmethane(DApEM) has been synthesized and identified.A study on superhighly sensitive colour reaction of Cr(Ⅵ)with DApEM has been carried out.In the presence of Mn(Ⅱ),Cr(Ⅵ) can react with DApEM to form a yellow product in phosphoric acid medium.Maximum absorbance is at 450 nm with molar absorptivity of 1 36×10 6L·(mol·cm) -1 .Beer's law is obeyed in the range of 2—32 μg Cr(Ⅵ)/L.This method has been satisfactorily applied to determination of chromium (Ⅵ) in environmental water.