KBrO_3-邻氨基酚体系催化动力学光度法测定微量Cu(Ⅱ)

Determination of Trace Cu(Ⅱ) in the Potassium Bromate-o-Aminophenol System by Catalytic Kinetic Spectrophotometric Method

在pH为4.5的HAc-NaAc缓冲溶液介质中,Cu(Ⅱ)能催化KBrO_3氧化邻氨基酚而显色,据此建立了测定微量Cu(Ⅱ)的新方法。方法的测定波长为430nm,反应温度为60℃时控制反应时间为6min,Cu(Ⅱ)在0.10~1.2μg/mL范围内吸光度与Cu(Ⅱ)的浓度呈良好的线性关系,相关系数r为0.9971。方法用于测定冶炼厂电解银废液中铜含量,相对标准偏差为2.49%(n=6),加标回收率在91.6%~99.4%之间。

In the medium of acetic-sodium acetate buffer solution （pH = 4. 5）, Cu（Ⅱ）can catalyze thecatalytic oxidation of potassium bromate o-aminophenol and make it coloration. Therefore,a new methodfor determination of trace copper was established. The determination wavelength was 430 nm, thereaction temperature was 60 C, and the reaction time was 6 min. The concentration of Cu（Ⅱ）andabsorbance showed good linear relationship in the concentration range of 0.10-1.2 g/mL forCu（Ⅱ）.The regression equation is x2=0. 5446%0. 1284 and the correlation coefficient is 0. 9971. This methodcan be used for the determination of copper content in smelter electrolytic silver waste liquid, the relativestandand deviations was 2.49%（n=6） ,and the recovery rate was between 91.6 %-99.4%.