阻抑动力学光度法测定痕量铜

摘要

研究了在磷酸介质中，痕量铜(Ⅱ)阻抑铬(Ⅵ)氧化二安替比林基-（3-溴）苯基甲烷显色的新指示反应及其动力学条件，建立了动力学光度法测定痕量铜(Ⅱ)的新方法。ΔA与铜(Ⅱ)浓度呈线性的范围为1.0～6.0μg／25mL，相对标准偏差为1.51％。用于铝合金样品的分析，结果满意。%A system of inhibitory kinetic spectrophotometic determination of trace copper(Ⅱ) was investigated. In the presence of manganese (Ⅱ) and phosphoric acid, trace amounts of Cu(Ⅱ) inhibit the reaction which chromium(Ⅵ) oxidizes DAmBM to form an orange-red product. The reaction condition was studied. The linear relationship between the ΔA and the concentration of Cu(Ⅱ) is found in the range of 1.0 to 6.0 μg/25mL, and the relative standard deviation is 1.51%. The method has been applied to the determination of trace copper in aluminum alloy with satisfactory results.