2-羟基-3-羧基-5-磺酸基苯基重氮氨基偶氮苯与铊反应的分光光度法研究

• 作 者: 郑国祥 郭忠先 邵勇 张淑云
• 机 构: 四川轻化工学院化学工程系
• 出 处: 分析试验室
• 发表日期: 1997年02期
• 关键词: 磺酸基 重氮 分光光度法 偶氮苯 显色反应 缓冲介质 吸光度 试剂空白 三氮烯类 最大吸收波长

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％。

In the presence of TritonX-100 in the NH3-NH4Cl buffer solution at pH 10.0 ~ 11.0, the interaction between thallium (Ⅲ) and 2-hydroxy-3-carboxy-5-sulfonated phenyldiazoaminoazobenzene HCS-DAA) to form a red complex with a compositional ratio of 1: 3. The maximum absorption wavelength and contrast were 510 nm and 80 nm, respectively. The apparent molar absorptivity was 1.52 × 105 L · mol-1 · cm-1. The linear range 0 ~ 0.70mg / L, the color reaction was completed immediately at room temperature, the complex was stable at least 2h. The method was applied to the determination of trace thallium in water samples, tobacco leaves and coal ash. The recoveries ranged from 90.0% to 101.4%. The relative standard deviations of the five determinations were no more than 4.6%.