钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯-Triton X-100体系的析相富集及痕量钴的光度测定

Phase Separation of Cobalt-4-[(5-Chloro-2-pyridyI)azo]-1,3-diaminobenzene Triton X-100 System and Spectrophotometric Determination of Trace Cobalt

本文研究了TritonX-100在浊点条件下对钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯(5-Cl-PADAB)络合物的析相条件,在pH4.0～6.0介质中,将胶束溶液加热到92±1℃,保持40min,络合物即被TritonX-100相富集。富集液在575nm测定吸光度,钴含量在0～4μg/5ml范围内服从比尔定律,干扰离子可在TritonX-100析相液中加入H_2SO_4消除。拟定的方法灵敏、简捷,已用于不经分离直接测定人发及自来水中痕量钴。

The optimum condition for the phase separation of cobalt-4-[(5-chloro-2-pyridyl)azo]-1,3-di-aminobenzene complex with Triton X-100 has been studied. At pH 4.0-6.0.the complex can be enriched in Triton X-100 phase when heating at 92 ±1℃ for 40 min in a boiling water bath. The absorbance is mea-suared at 575 nm, and Beer' s law is obeyed in the range from 0 to 4. 0μg/5 ml for Co. The interfering elements can be eliminated by adding H2SO4 into the surfactant phase. The highly sensitive method proposed has been applied to the direct spectrophotometric determination of trace cobalt in hair and tap water without separation.