双氧水氧化1-(2-吡啶偶氮)-2-萘酚动力学光度法测定痕量硒  

Determination of Selenium by Catalytic Kinetic Spectrophotometry in Hydrogen Peroxide-PAN System

作　　者：严进[1] 

机构地区：[1]南通职业大学化学与生物工程学院,江苏南通226007

出　　处：《广州化工》2016年第21期132-134,共3页GuangZhou Chemical Industry

摘　　要：在盐酸介质中,Se（IV）对1-（2-吡啶偶氮）-2-萘酚（PAN）褪色反应有灵敏的催化作用,建立了测定Se（IV）的动力学新方法。线性范围在0~0.9μg/50 m L时符合比耳定律,检出限为2.2×10-10g·m L-1。催化反应为动力学零级反应,表现活化能为111.28 k J/mol,反应速率常数为7.15×10-4s-1。考察了20多种共存离子的影响,表明本方法具有较好选择性。方法用于茶叶样品中痕量硒的测定,相对标准偏差小于3.9%,回收率在96.2%~105.5%之间。A new kinetic spectrophotometric method for determination of trace Se （IV） was proposed. Se （IV） can sensitively catalyze the discoloration reaction of 1- （2-pyridylazo） -2-naphthol by hydrogen peroxide in HC1 medium. The line arrange for determination of Se（IV） was 0 -0. 9μg/50 mL with the detection limit of 2.2×10-1·g ·mL-1. The resahs from the studies suggested that the catalytic reaction was zero-order and the apparent activationenergy of this reaction was 111.28 kJ ·mo1-1 , and the apparent rate constant was 7.15×10-4 s-1. The interferences of foreign ions were also studied. The procedure was used to determine Se （IV） in tea samples, with the relative standard deviation of below 3.9% and the average recovery of 96. 2% - 105.5%.

关 键 词：催化动力学光度法 硒(IV) 双氧水 PAN 

分 类 号：O657.32[理学—分析化学]