催化动力学分光光度法测定痕量钒(Ⅴ)

Catalytic Kinetic Spectrophotometric Determination of Trace Vanadium(Ⅴ)

在醋酸介质中 ,以抗坏血酸作活化剂 ,痕量钒 (Ⅴ )对溴酸钾氧化邻苯三酚红褪色的指示反应有灵敏的催化作用。研究了该反应的最佳实验条件和动力学参数 ,建立了一种测定超痕量钒 (Ⅴ )的新方法 ,该法选择性强、操作简便、快速 ,其线性范围为 0 .8～ 4.0 μg/L钒 (Ⅴ ) ;检出限为 6.8× 1 0 -9g/L。方法用于生物样品中痕量钒 (Ⅴ )的测定 ,结果满意。

A catalytic kinetic spectrophotometric method for the determination of trace ultra vanadium(Ⅴ) based on the redox reaction between potassium bromate and Pyrogallon Red in the presence of ascorbic acid as an activator in acetic acid medium has been proposed .The optimum conditions and kinetic parameters have been investigated.The detection limit for vanadium(Ⅴ) is 6.8×10 -9 g/L. The calibration graph is linear for 0.8～4.0 μg/L V(Ⅴ). The method has been applied to the determination of trace vanadium(Ⅴ) in shrimp, fish, apple , banana, pear and orange samples with satisfactory results.