新显色剂1-(对-偶氮苯)-3-(5-硝基-2-吡啶)-三氮烯的合成及其与镉的显色反应

Studies on synthesis of 1-(p-azophenyl)-3-(5-nitro-2-pyridyl)-triazene and its color reaction with cadmium(Ⅱ)

报道了新显色剂 1 - (对 -偶氮苯 ) - 3- ( 5-硝基 - 2 -吡啶 ) -三氮烯 ( APNPT)的合成及其与镉的显色反应。在非离子表面活性剂 OP的存在下 ,p H1 0 .8时 ,镉 ( )与 APNPT形成 1∶ 2的稳定红色配合物 ,其最大吸收波长为 52 5nm,表观摩尔吸光系数为 1 .7× 1 0 5L· mol-1· cm-1,线性范围为 0～ 2 .8μg/1 0 m L,是目前测定微量镉的高灵敏显色反应之一 ,所拟方法已用于水样中微量镉 ( )的测定。

This paper reports the synthesis of the new reagent 1 (p azophenyl) 3 (5 nitro 2 pyridyl) triazene (APNPT) and the color reaction of APNPT with cadmium(Ⅱ).In the presence of non ionic surfactant OP, the reagent formed a red complex with cadmium(Ⅱ) with the molar ratio of 1∶2 at pH 10.8. The maximum absorption of the complex is at 525 nm and the molar absorptivity is 1.7×10 5 L·mol -1 ·cm -1 . Beer′s law is obeyed in the range of 0～2.8μg/10 mL. This is one of color reaction with high sensitivity for determination of cadmium(Ⅱ),the method was used to determine cadmium(Ⅱ) in water samples.