催化动力学分光光度法测定水样中的痕量铜

DETERMINATION OF ULTRATRACE AMOUNTS OF COPPER(ll) BY LTS CATALYTIC EFFECT ON THE OXIDATIVE COUPLING REACTION

在pH值为7.6的磷酸二氢钾-硼砂缓冲介质中,痕量铜(Ⅱ)可灵敏地催化H2O2氧化N,N-二甲基苯胺(DMA)与3-甲基-2-苯并噻唑-酮腙(MBTH)的氧化还原显色反应.研究了该反应的最佳条件,建立了催化动力学分光光度法测定痕量铜的新方法.该方法的线性范围为(1.5～7.7) μg/L,检出限为0.463 0 μg/L.该法被用于测定水样中铜的含量,获得满意结果.

A spectrophotometric method was developed for the determination of ultratrace amounts of copper （Ⅱ） based on its catalytic effect on the oxidative coupling reaction of 3 - methyl - benzothiazolinone hydrozone with N, N - Dimethylaniline to produce an intensely colourd dye （ （ max = 590 nm） in the presence of hydrogen peroxide. In this reaction, 1,10 - Phenanthroline acted as an effective activator for the catalysis of copper（Ⅱ）. By measuring the absorbance of the dye, copper（Ⅱ） can be determined at the （ 1.5 - 7.7 ） μg/L level. The detection limit was 0.46 μg/L. The proposed method was successfully applied to the determination of copper（Ⅱ） in some water samples.