钌催化高碘酸钾氧化偶氮胂I动力学光度法测定痕量钌

Kinetic Spectrophotometry Determination of Ruthenium Based on Its Catalytic Activity for Oxidation of Arsenazo I by Potassium Periodate

在 H3 PO4、90± 0 .5°C水浴条件下 ,Ru( )催化高碘酸钾氧化偶氮胂 I的褪色反应基础上 ,提出了测定钌的新催化光度法。钌质量浓度在 0～ 0 .0 8μg/1 0 m L范围内符合比尔定律 ,检出限为3.47× 1 0 -4μg/m L。对 0 .0 5 μg/1 0 m L Ru( )测定的相对标准偏差为 1 .47% ( n=1 0 )。该催化反应是一级反应 ,表观活化能为 5 8.82 k J/mol。此法已用于了某些冶金产品和矿石中钌的测定 ,相对标准偏差为 1 .73%～ 2 .0 3% ,标准加入回收率为 97%～ 1 0 5 %。

A new catalytic spectrophotometric method has been developed for the determination of ruthenium(Ⅲ) based on its catalytic activity for oxidation of arsenazo I by KIO 4 in H 3PO 4 medium at 90±0.5°C. Beer's law was obeyed in the Ru(Ⅲ) concentration range of 0~0.08 μg/10 mL, and the detection limit was 3.47×10 -4 μg/mL. The relative standard deviation for the determination of Ru(Ⅲ) at the concentration of 0.05 μg/10 mL was 1.47%( n =10). The results of the studies on the kinetic parameters suggested that the catalytic reaction is first order and the apparent activation energy of this reaction is 58.82 kJ/mol. The method has been successfully applied for the determination of trace amount of ruthenium in some ore and metallurgy products with the relative standard deviation of 1.73%~2.03% and the recovery of 97%~105%.