高碘酸钾-偶氮氯膦mk催化动力学光度法测定痕量钌

Catalytic kinetic spectrophotometric determination of trace ruthenium(Ⅲ) with potassium periodate and chlorophosphonazo-mk system

研究了在磷酸介质中，痕量钌（Ⅲ）催化高碘酸钾氧化偶氮氯膦mk褪色反应特性，测定了反应级数、反应速率方程和表观活化能，拟定了反应的最佳条件，建立了一个测定痕量钌的催化动力学新方法。该方法的检出限为6．19×μg／mL，25mL溶液中，钌（Ⅲ）的线性范围为0．12～1．1μg，大多数共存离子不干扰测定。用于测定冶金产品和矿石中的钌。测定值与原结果相吻合，回收率在98．8％～101．0％之间，相对标准偏差不超过2．5％。

The catalytic effect of ruthenium（Ⅲ） on the oxidation decolorizing reaction of chlorophosphonazomk by potassium periodate in phosphoric acid medium was investigated. Based on this, the determination of ruthenium（Ⅲ） by the kinetic spectrophotometry was established. The rate equation, reaction order and apparent activation energy of the catalytic reaction were also studied. In 25 mE solution, the linear range for the determination of Ru（Ⅲ） is 0.12 - 1.1 μg with detection limit of 6.19 × 10^-10g/mL, and most coexisting ions don＇ t interfere in the determination. The method has been applied to the determination of trace ruthenium in ores and metallurgy products and the results are consistent with the original values, the recoveries are in the range of 98.8% 101.0% with RSD no more than 2.5%.