催化褪色光度法测定痕量钍(Ⅳ)的研究

STUDY ON THE DETERMINATION OF TRACE THORIUM(Ⅳ) BY CATALYTIC KINETIC DISCOLORING SPECTROPHOTOMETRY

在硝酸介质中 ,钍 (Ⅳ )能较灵敏地催化过氧化氢氧化苦胺酸偶氮变色酸褪色的指示反应 ,研究了该催化褪色反应的最佳条件及动力学参数 ,建立了一种新的动力学测定钍 (Ⅳ )的方法。线性范围 (0 - 2 .5 ) μgTh4+ / 2 5mL ,检测限为 1.6 73× 10 -9g/mL。用于稀土矿中钍 (Ⅳ )的测定 。

In this paper,a method has been studied for the determination of trace Th(Ⅳ) based on the fact that Th(Ⅳ) in nitrate solution may catalyze the discoloration of picraminicazochromotropic acid by hydyogen peroxide.The linear range is (0-2.5)μg/25 mL.The limit of detection is 1.673×10 -9 g/mL,it has been used in the determination of trace Th(Ⅳ) in rare earth with a good result.