新试剂“1.6一双[(3′,4′-二羟基蒽醌-2′-磺酸)偶氮]联苯”与镉(Ⅱ)的显色反应研究

Synthesis of 1.6-dual[(3′,4′-Dihydroxyanthraquinone-2′-sulfonic acid)azo] pheny Ibenzene and its color Reaction with Cadmium(Ⅱ)

本文研究了用联苯胺与茜素红合成的双偶氮显色剂 1 .6一双 [(3′4,′ -二羟基蒽醌 - 2′ -磺酸 )偶氮 ]联苯 (简称 ,d -DHASAB)与镉 (Ⅱ )的显色反应。以 1 0 %的吐温 - 80作表面活性剂 ,在pH =9.0 4的HBO3-KCl-NaOH缓冲介质中 ,镉 (Ⅱ )与d -DHASAB形成 2∶1的紫红色配合物 ,该配合物的最大吸收峰位于 550nm处 ,其表观摩尔吸光系数ε550 =2 .64× 1 0 4 L/(mol·cm) ,镉 (Ⅱ )浓度在 0～ 7.5μg/1 0mL范围内符合比尔定律。所拟方法无须分离 ,可直接用于矿样、合金中微量Cd的测定 ,结果满意。

In this paper,a new reagent d-DHASAB has been synthesized and its colour reaction with cadmium is studied.In the persence of nonionic surfacants Tween-80,in H 3BO 3+KCl+NaOH buffer solution of pH 9.04,Cd(Ⅱ) can form a 2∶1 complex with d-DHASAB.The complex shows maximium absorption wavelength at 550 nm.The determination of trace cadmium with spectro-photometry is described and the molar absorptivity is 2.64×10 4 L/(mol·cm).The Beer's law is obeyed in the range of 0～7.5 μg/10 mL.The method has been applied to the deter-minatior of the cadmium in oves and alloys with satis factory results.