三阶导数分光光度法同时测定铜、钴与镉

Third Derivative Spectrophtometric Simultaneous Determination of Copper,Cobalt and Cadmium

采用三阶导数光谱技术，以ｍｅｓｏ－四（４－三甲铵基苯基）卟啉作显色剂分光光度法同时测定了微量的铜、钴与镉。方法中以铅离子掩蔽过剩试剂的吸收峰，然后进行三级微分求导，可以使铜、钴、镉吸收峰完全分开，于４１５ｎｍ、４３４ｎｍ及４３８ｎｍ处同时测定３元素含量，由三阶导数光谱的吸光值可求算出配合物的三阶导数摩尔吸光系数分别为：１．１１×１０６、３．９５×１０５及６．４７×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。

A method of third derivative spectrophotometric simultaneous determination ofmicro amount of copper,cobalt and cadmium with meso-tetrakis[4-(trimethylammonium)phenyl]porphine has been established.The absorption maxima of the third derivative spectrafor copper,cobalt and cadmium complexes were localed at 412nm,434nm,438nm,respec-tively,They could be used for simultaneous determinatlon of copper,cobalt and cadmium. The molar absorptivities of third derivative spectra were 1.11×10 6(Cu),3.95×10 5(Co)and6. 47×105(Cd)L· mol-1· cm-1,respectively,The method has been used to determine syn-thetic mixtures of copper,cobalt and cadmium,and satisfactory results were obtained withrelative errors<4%.