钙指示剂与铜显色反应的研究和应用

Researches and applicationes of the color reaction between copper(Ⅱ)and calcon

以钙指示剂为分光光度法测定铜的新显色剂,系统研究其反应条件并拟定一种测定铜的方法。在 pH 为10～13的 NH_3-NH_4Cl 介质中,钙指示剂在室温下与铜迅速反应,形成最大吸收波长为540mm 的紫红色配合物,在最大吸收波长处,配合物的表观摩尔吸光系数为1.6×10~4。比尔定律适用范围为0～2μCu_^(2+)/mL。本法应用于纯铝、钢样中铜的测定。

A new spcctrophotometric method for detcrmination of copper(Ⅱ)is reports,which is based on the colour reaction of copper(Ⅱ)with 2-hydroxy(-hydroxy-4-sulfonic-1- diazo-naphthylene-3-naphthenic acid(Calcon).The copper(Ⅱ)formsred complex with calcon in Ammonia-Ammonium Chloride buffer solution at pH range of 10 to 13,the maximum absorption wavelength of the complex is located at 540mm.The apparent molar absorption coefficient is 1.6×10~4L·mol^(-1)·cm^(-1).Beer's law is obeyed within a concentra- tion range of 0-50μg Cu^(2+)/25mL.The method has been used to the determination of trace amornt of copper in aluminium and steel samples with satisfactory results.