邻羧基苯基重氮氨基偶氮苯胶束增溶分光光度法测定痕量铊  

Determination of Trace Thallium with o-Carboxy- Benzenediazoaminoazobenzene by Micellar Solubilization Spectrophotometry

作　　者：唐谦[1,2] 蔡蜀穗[1,2] 郑国祥 郭忠先[1,2] 张淑云 

机构地区：[1]西南农业大学食品科学学院 [2]四川轻化工学院化工系

出　　处：《广东工业大学学报》1997年第S1期62-65,共4页Journal of Guangdong University of Technology

摘　　要：在乳化剂ＯＰ存在下。于１．１～３．０ｍｏｌ／Ｌ氨水介质中，Ｔｌ（Ⅲ）与邻羧基苯基重氯氨基偶氮苯（ＣＤＡＡ）形成组成比为１∶２的稳定的橙红色配合物，其吸收峰波长在５１２ｎｍ，对比度Δλ＝９２ｎｍ，表观摩尔吸收系数为１．３４×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。室温下显色反应立即完成，配合物至少稳定８ｈ，线性范围为０～０．８０ｍｇ／Ｌ．方法用于水样、烟叶和煤灰中痕量铊的分析，回收率为９０．０％～１０１．４％，相对标准偏差不大于４．６％（ｎ＝５）。Abstract A highly sensitive spectrophotometric procedure is investigated for the determination of trace thallium (Ⅲ) with o carboxybenzenediazoaminoazo benzene(CDAA)in the presence of p￣octylpolyedhyleneglycol phenylether(OP).In ammonia medium of 1.1～3.0 mol/L,the red complex formed by thallium(Ⅲ) and CDAA has a maximum absorption at 512 nm,with contrast Δλ=92nm,and its apparent molar absorptivity is 1.34×10 5L·mol -1 ·cm -1 ,Sandell sensitivity is 1 53×10 -3 μg·cm -2 .The color reaction complete immediately and the color is stable for at least 8h.The molar ratio of thallium(Ⅲ)to CDAA in the complex is found to be 1∶2.Beet′s law is obeyed in the concentration range of 0～0.80mg/L for thallium.The proposed method has been applied to the determination of trace thallium in cigarette leaf.coal ash and tap water with the recovery of 90.0%～101.4% and the RSD(n=5) of less than 4.6%. Key\ words\ Thallium;spectrophotometry;o carboxybenzenediazoaminoazobenzene

关 键 词：铊 分光光度法 邻羧基苯基重氮氨基偶氮苯 

分 类 号：O657.32[理学—分析化学]