铜与洋茉莉基荧光酮反应的分光光度研究及应用

Spectrophotometric Studies and Applications on the Reaction of Copper with PIF

本文研究了在ＣＰＢ存在下洋茉莉基荧光酮（ＰＩＦ）与铜的显色反应。结果表明：在ｐＨ５．８－６．６的六次甲基四胺－ＨＣｌ缓冲介质中，Ｃｕ２＋与ＰＩＦ形成１∶２的蓝紫色配合物，以５２４ｎｍ为参比波长、５８２ｎｍ为测定波长，用双波长吸光光度法测得表观摩尔吸光系数为１．１１×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。铜在０—０．２０μｇ／ｍＬ范围内服从比耳定律。用于高纯稀土氧化物中微量铜的测定，相对误差不大于３．７％。相对标准偏差不大于２．０％（ｎ＝６）。

A highly sensitive color reaction of copper(Ⅱ) with piperonal fluorone (PIF) in the presence of CPB has been studied in detail.The results showed that copper(Ⅱ) with PIF forms 1∶2 blueviolet complex in a (CH 2) 6N HCl buffer medium of pH5.8-6.6.The absorptivity coefficient of the complex determined by dual wavelength spectrophotometry is 1.11×10 5L·mol -1 ·cm -1 .Beer's law is obeyed in the concentration range of 0-0.2μg·mL -1 for copper.The proposed method has been applied to the spectrophotometric determination of microamounts of copper in highly pure rare earth with the relative error and the relative standard deviation( n =6) of less than 3.7% and 2.0%,respectively.