摘要
于ｐＨ１０．０～１１．０的ＮＨ３－ＮＨ４Ｃｌ缓冲介质中，在ＴｒｉｔｏｎＸ－１００存在下，铊（Ⅲ）与２－羟基－３－羧基－５－磺酸基苯基重氮氨基偶氮苯（ＨＣＳ－ＤＡＡ）形成组成比为１∶３的红色配合物，其最大吸收波长和对比度分别为５１０ｎｍ和８０ｎｍ，表观摩尔吸光系数为１．５２×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，线性范围为０～０．７０ｍｇ／Ｌ，室温下显色反应立即完成，配合物至少稳定２ｈ。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％，５次测定的相对标准偏差不大于４．６％。
A highly sensitive color reaction of thallium(Ⅲ) with 2 hydroxy 3 carboxy 5 sulfobenzenediazoarminoazobenzene (HCSDAA) in the presence of Triton X 100 was studied in detail.In NH 3 NH 4Cl buffer medium at pH 10.0～11 0,the red complex formed has a maximum absorption at 510nm with contrast △λ=80nm and its apparent molar absorptivity is 1.52×10 5L·mol -1 cm -1 ,and Sandell sensitivity is 1.35×10 -3 μg.cm -2 .The molar ratio of thallium (Ⅲ) to HCSDAA in the complex is found to be 1∶3.Beer's law is obeyed in the concentration range of 0～0 70mg/L for thallium.The proposed method has been applied to the spectrophotometric determination of trace thallium in cigarette leaf,coal ash and tap water with the recovery of 90.0%～101 4% and the relative standard deviation ( n =5) of less than 4.6%
出处
《分析试验室》
CAS
CSCD
1997年第2期21-24,共4页
Chinese Journal of Analysis Laboratory
基金
四川省教委科研基金
关键词
铊
分光光度法
HCS-DAA
Thallium determination
spectrophotometry
2 hydroxy 3 carboxy 5 sulfobenzenediazoaminoazobenzene
