摘要：

在硫酸介质中以及在十六烷基三甲基溴化铵（CTMAB）存在条件下，对痕量Cr（Ⅵ）催化溴酸钾氧化孔雀石绿褪色的反应进行了研究，建立了测定痕量Cr（Ⅵ）的新方法，研究了影响褪色反应的因素。在优化实验条件下，方法的线性范围0~60 μg/L，检出限为7.5×10^-4 μg/L。该法用于测定电镀废水中的铬（Ⅵ），相对标准偏差（n=6）为2.1%，结果与原子吸收法相符。

关键词: 铬(Ⅵ), 分光光度法, 十六烷基三甲基溴化铵(CTMAB), 孔雀石绿, 电镀废水

Abstract:

A new method for the determination of trace Cr(Ⅵ) has been developed,based on catalytic effect of chromium(Ⅵ) on the oxidative decoloration reaction of malachite green oxidized with potassium bromate,and cetyl trimethyl ammonium bromide(CTMAB) as sensitizer in sulfuric acid medium. The factors affecting decoration reaction are studied. Under optimized experimental conditions,the linear range of the determination is 0－60 μg/L for chromium(Ⅵ),and the detection limit 7.5×10^-4 μg/L. The method is successfully applied to the determination of chromium(Ⅵ) in electroplating wastewater,its relative standard deviation(n=6) is 2.1%. The results are consistent with those obtained by atomic absorption spectrometry.

Key words: chromium(Ⅵ), spectrophotometry, cetyl trimethyl ammonium bromide(CTMAB), malachite green, electroplating wastewater

中图分类号: 

• O657