Os(Ⅳ)—MR—ClO_3^-—As(Ⅲ)体系的动力学研究及应用

Kinetic Study on the System of Os(Ⅳ) - As(Ⅲ) - ClO_3^- Methyl Red and Its Application

提出了一种制备值化剂Os(Ⅳ)的新方法。利用在HAC-NaAc缓冲溶液中,锇(Ⅳ)对反应ClO_3^-—As(Ⅲ)—MR的强烈催化作用,以甲基红为指示剂,单扫描示波极谱为检测技术,研究了甲基红(MR)的示波极谱特性和反应体系ClO_3^-—As(Ⅲ)—Os(Ⅳ)—MR的动力学,提出了可能的反应机理,并用固定时间法拟定了一个锇的催化反应—示波极谱新方法,该法的线性范围为24×10^(-10)～72×10^(-9)mol/L,已用于合成试样中锇的分析、

The oscillopolarographic behavior of methyl red (MR) in acidic mdia was investigated. A procodure for the preparation of catalyst Os(Ⅳ)was described and its composition was inferred experimentally as Os(OH)_4(H_2O)_2. The kinetics of the catalytic reaction system of Os (Ⅳ)-As(Ⅲ)-ClO_3^--MR was studied by using oscillopolarograph as detection technique and methyl red as indicator. On basis of the achievement of kinetic study, a highly sensitive method for determination of ultratrace amounts of osmium was developed, and found that the amenable range is 2A×10^(-4)～7.2 ×10^(-9)mol/L. The method has been used to measure osmium in synthetic sample with excellent results.