2-甲硫基苯基重氮氨基偶氮苯的合成及其与钴显色反应的研究

Synthesis of 2-methylthio-phenyl diazoamino azobenzene and study on its chromogenic reaction with cobaltⅡ

合成了新试剂 2 甲硫基苯基重氮氨基偶氮苯 ,并研究了它与Ｃｏ 的显色反应。试验表明 ,在Ｎａ2 Ｂ4Ｏ7-ＮａＯＨ缓冲溶液中 ,ＴｒｉｔｏｎＸ 1 0 0存在下 ,试剂与Ｃｏ 形成 2∶1型红色络合物 ,最大吸收波长为 540ｎｍ ,表观摩尔吸光系数为 2 42×1 0 5。在 2 5ｍＬ溶液中钴质量在 0～ 1 0 μｇ范围内遵守比尔定律。用本法测定工业废水和维生素Ｂ1 2 针剂中痕量钴 ,获得满意结果。

A new chromogenic reagent(2-methylthio-phenyl diazoamino azobenzene,MTDAA) was synthesized and the color reaction of MTDAA with cobalt*' was studied.Results showed that a red complex of MTDAA and Co*' was formed in buffer solutions of Na_2B_4O_7-NaOH at pH 9.5-10.5 in the presence of Triton X-100.The complex gave a maximum absorption at 540 nm with an apparent molar absorptivity of 2.42×10~5 L· mol· cm^(-1).Beer's law was obeyed in the range of 0-10 μg cobalt in 25 mL of solution.