2-(2-喹啉偶氮)-4,5-二甲基苯酚光度法测定水中的铜

Spectrophotometric Determination of Copper in Water with 2-(2-Quinolinlazo)-4,5-Dimethylhydroxybenzen

研究了2-(2-喹啉偶氮)-4,5-二甲基苯酚(QADMP)与铜(Ⅱ)的显色反应,在pH为4 0的HAc-NaAc缓冲介质中,CTMAB存在下,QADMP与铜(Ⅱ)生成分子比为2∶1的稳定红色配合物,该配合物λmax=561nm,摩尔吸光系数ε为4 56×104L·mol-1·cm-1,铜(Ⅱ)含量在0～0 4mg/L内符合比耳定律,该方法用于水样中微量铜的测定,结果满意。

The color reaction of copper (Ⅱ) with 2-(2-Quinolinlazo)-4,5-Dimethylhydroxybenzen was studied. In the presence of pH = 4.0 HAc-NaAc buffer solution and CTMAB medium, QADMP reacts with copper (Ⅱ) to form a stable 2∶1 complex. The molar absorption is 4.56×10~4 L·mol^(-1)·cm^(-1) at 561 nm. The content of copper is in range of 0～0.4 mg/L that obeys Beer's law. This method can be applied to the determination of copper in water with satisfactory results.