过氧化氢-甲基红体系催化动力学光度法测定痕量EDTA  

Determination of Trace EDTA by Cataiysis Kinetic Spectrophotometry in Hydrogen Peroxide-methyl Red System

作　　者：严进[1] 

机构地区：[1]南通职业大学化学与生物工程学院,江苏南通226007

出　　处：《广州化工》2015年第17期149-150,197,共3页GuangZhou Chemical Industry

摘　　要：鉴于在盐酸介质中, EDTA对过氧化氢氧化甲基红反应具有明显的催化作用,据此建立了一种新的测定EDTA的催化动力学分光光度法。研究了该催化褪色反应的动力学条件和参数。在测定波长520 nm下,测定方法的线性范围1.0~9.0μg/25 mL,检出限为2.76×10-9 g/mL。催化反应为动力学零级反应,表现活化能为38.72 kJ/mol,表观反应速率常数1.21×10-3 s-1。该方法用于电厂锅炉清洗废水EDTA的测定,相对标准偏差小于3.8%,试样加标回收率为95.5%~106.0%。A catalytic spectrophotometric method for the determination of trace EDTA was speeded up based on the cataiysis effect of EDTA on the oxidation of methyl red by hydrogen peroxide in hydrochloric acid medium. The optimum kinetic conditions of the catalytic reaction were investigated. The wavelength for the determination was 520 nm. The linear range for determination of EDTA was 1. 0~9. 0 μg/25 mL with the detection limit of 2. 76 ×10-9 g/mL. The results from the studies suggested that the catalytic reaction was zero-order and the apparent activation energy of this reaction was 38. 72 kJ/mol, and the apparent rate constant was 1. 21×10-3 s-1. The procedure was used to determine to clean waste water in EDTA of power station boiler, with the relative standard deviation of below 3. 8% and the average recovery of 95. 5% ~106. 0%.

关 键 词：催化动力学分光光度法 甲基红 过氧化氢 

分 类 号：O657.32[理学—分析化学]