镉(Ⅱ)-4-甲醛基重氮氨基偶氮苯显色反应的研究

A New Colour Reaction of Cadmium With 4-Formacyl Benzendiazoaminoazobenzene

本文研究了Cd(Ⅱ)与4-甲醛基重氮氨基偶氮苯的显色反应。试验结果表明:在TritonX-100的存在下,pH9.50的Na_2B_4O_7-NaOH缓冲体系中,显色反应的灵敏度高,络合物的最大吸收峰在525nm处,表观摩尔吸光系数为1.33×10~5L·mol^(-1)·cm^(-1),Cd(Ⅱ)浓度在0～10μg/25ml范围内符合比耳定律。利用阴离子交换树脂(717)小柱分离干扰离子后,测定地质试样中微量镉,结果满意。

In the presence of Triton X-100 and in a medium at pH 9. 50,cadmium with 4-formacyl benzendia-zoaminoazobenzene(4-CHO-cadion)formed a complex.Its apparent molar absorptivity is 1. 33×105 L·mol-1 · cm-1 at 525 nm, Beer's law is obeyed in the range of 0-10μg/25 ml for cadmium. Interfering ions are separated by anion exchanger. This method has been applied to the determination of cadmium in ores.