银-过硫酸钾-钍试剂体系催化光度法测定痕量银

Catalytic-Kinetic Spectrophotometric Deterimnation of trace Silver with a system of Silver - potassium persulfate -Thoron

本文研究了在pH=4.5的HAc-NaAc介质中,以2,2’-联吡啶为活化剂,过硫酸钾氧化钍试剂催化动力学光度法测定痕量银的新方法。本法检测限为2.49×10-3μg/mL;相对标准偏差为3.3%(n=11);线性范围为0.004~0.048μg/mL。可用于测定黑白相纸液中的银和氯化银的溶度积。

A new catalytic spectrophotometric method for the determination of trace silver has been developed in HAc-NaAc(pH=4.5)buffer medium. This method is based on the catalytic oxidation of thoron by potassium persulfate in the presence of 2,2'-dipyridyl as an activator. The detection limit is 2.49×10^(-3) μg/mL, the relative standard deviation is 3.3%, the linear range of determination is 0.004~0.048 μg/mL for Ag. This method has been successfully used to determine silver in the solution of the black-and-white photographical paper and the solubility product of silver