新显色剂1-羟基-2-(5-NO_2-2-吡啶偶氮)-8-氨基3,6-萘二磺酸与铜显色反应的研究

Study on colour reaction of copper with 1-hydroxy-2- (5-nitro-2-pyridylazo)-8-aminonaphthalene-3,6-disulfonic acid

探讨了新显色剂 1 羟基 2 ( 5 NO2 2 吡啶偶氮 ) 8 氨基 3,6 萘二磺酸 (简称 5 NO2 PAH)与铜离子显色的适宜条件及其共存离子的影响 ,建立了 5 NO2 PAH测定铜的新显色反应体系。在pH 7.0～ 1 0 .0范围内 ,铜与试剂形成稳定的1∶2配合物 ,其最大吸收峰位于 65 3nm ,表观摩尔吸光系数εCu=4.68× 1 0 4L·mol- 1 ·cm- 1 ,铜的浓度在 0 μg/1 0mL～ 1 4μg/1 0mL范围内遵守比尔定律。

The optimum condition for colour reaction of copper with a new reagent 1 hydroxy 2 (5 nitro 2 pyridylazo) 8 aminonaphthalene 3,6 disulfonic acid (5 NO 2 PAH) was studied. The experimental results showed that, in the pH range of 7.0～10.0, copper could react with 5 NO 2 PAH and form a stable complex which exhibited a maximum absorption at 653nm with apparent molar absorptivity of 4.68×10 4 L·mol -1 ·cm -1 . Beer's law was obeyed in the range of 0～14 μg/mL copper. The method was applied to determination of copper in alloy samples with satisfactory results.