新显色剂二溴羧基偶氮胂的合成及其光度法测定铈组稀土的研究  

Study on a new chromogenic reagent——Dibromocarboxyarsenazo and its application to spectrophotometric determination of ceriumsubgroup rare earths

作　　者：潘教麦[1] 吴岚[1] 徐钟隽[1] 

机构地区：[1]华东师范大学化学系

出　　处：《化学试剂》1990年第3期129-131,132,共4页Chemical Reagents

摘　　要：合成了新显色剂二溴羧基偶氮胂,研究了其与稀土离子的显色反应。在盐酸、磷酸、高氯酸、硫酸介质中试剂与铈组稀土形成稳定的配合物。最大吸收在632nm 处。铈配合物的摩尔吸光率为1.40×10~5l·mol^(-1)·cm^(-1),高于已常用的变色酸双偶氮胂、膦类试剂。The synthesis and purification of dibromocar-boxyarsenazo are described.Cerium reacts withthe reagent to form a colored complex instrongly acidic medium.The absorption maximaof the reagent and complex are at 535 nm and632 nm respectively.Under the conditionsemployed,Beer's law is obeyed in the range of0～20 μg Ce in 25 ml of solution.The molarabsorptivity was found to be 1.40×10~5 l·mol^(-1)·cm^(-1),which is superior to those of other cur-rently used methods.Most of foreign ions inmg-amount do not interfere with the reaction.

关 键 词：铈组稀土 二溴羧基 偶氮胂 光度法 

分 类 号：O614.332[理学—无机化学]