摘要：

在硫酸介质中,铋(Ⅲ)对碘酸钾氧化生物染料曙红B的褪色反应有强烈的催化作用,据此建立了测定痕量铋(Ⅲ)的催化动力学新方法。体系催化反应吸光度(A)和非催化反应吸光度(A0)的变化值(ΔA)与铋(Ⅲ)浓度在0.2～1.2 mg/L范围内呈良好的线性关系。方法检出限为7.22×10-11 g/L,表观速率常数为2.97×10-4 s-1,表观活化能为36.74 kJ/mol。将该法用于水体中痕量铋(Ⅲ)的测定,结果满意,回收率为98.5%～104.2%。

关键词: 曙红B, 催化动力学光度法, 痕量铋(Ⅲ)

Abstract:

In H₂SO₄ media, bismuth(Ⅲ) has strong catalytic effect on the decolorizing reaction of potassium iodate oxidizing biological dyestuff, bromeosin B. According to this phenomenon, a new method of trace bismuth(Ⅲ) determination by catalytic kinetics has been established hereby. The absorbency variation value ΔA of system catalytic reaction(A) and non-catalytic reaction(A0) have good linear relationship with bismuth(Ⅲ) whose mass concentration is in the range of 0.2-1.2 mg/L, and the detection limits is 7.22×10-11 g/L. The apparent velocity constant is 2.97×10-4 s-1, and apparent activated energy is 36.74 kJ/mol. The method has been applied to the determination of trace bismuth(Ⅲ) in water body. The results are satisfactory and its recovery rate is 98.5%-104.2%.

Key words: bromeosin B, catalytic kinetics spectrophotometry, trace bismuth（Ⅲ）

中图分类号: 

• O657.3