摘要
本文研究了新显色剂5-Br-TAMB与铑(Ⅱ)的显色反应。在pH5.0～7.0的水溶液中,铑(Ⅱ)与5-Br-TAMB形成1:2型稳定的蓝色配合物,其最大吸收波长为674nm,表观摩尔吸光系数为1.1×10~5L·mol^(-1)·cm^(-1),铑(Ⅱ)含量在0～12μg/ml范围内服从比耳定律。采用加入适量EDTA的方法消除了Cu^(2+)、Co^(2+)、Ni^(2+)等干扰离子。建立了一个在二元配合物体系中具有高灵敏度及选择性、稳定、简便地吸光光度测定微量铑(Ⅱ)的新方法。
The chromogenic reaction of rhodium(Ⅱ)with reagent 2-〔2-(5-bromothiazoly)azo)-5-dimethylaminobenzoic acid(5-Br-TAMB)has been investigated. In the solution of pH 5.0～7.0, Rh(Ⅱ)reacts with 5-Br-TAMB to form a 1:2 binary complex after heated in boiling water bath for 5 min, it can be stable for 24 h. The absorbance maximum is measured at 674 nm with the molar absorptivity being 1.1×10~5 L·mol^-1·cm^-1. Beer＇s law is obeyed in the range of 0～12μg/25ml for Rh(Ⅱ). With EDTA served as masking agent, common ions do not interfere. This method has been applied to the determination of trace rhodium(Ⅱ)in the Rh-sieve, Rh-MgO and Rh-active carbon catalysts with satisfactory results.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1991年第9期1047-1049,共3页
Chinese Journal of Analytical Chemistry
