摘要
本文采用分光光度法研究了碱性介质中二过碲酸合铜(Ⅲ)配离子氧化丙酮酸钾的反应动力学。结果表明当丙酮酸钾(py)[py]》[Cu(Ⅲ)]时,反应对Cu(Ⅲ)是准一级反应,表观速率常数Kobs随着[py]的增加而增加,但随着的增加而减小,有正盐效应。提出了包含前期平衡的反应机理,据此求出了不同温度下速控步骤的速率常数及25℃的活化参数,并且能圆满地解释所有实验事实。
The kinetics of oxidation of potassium pyruvate by ditellurato-cuprate(Ⅲ) complex ion was studied by spectrophotometrically in alkaline medium .It was found that the rate with respect to [Cu(Ⅲ)] is unity. A linear relationship between [py]/ kobs and [py] was observed, where kobs stands for pseudo-first-order rate constant kobs decreases with the increase of or [OH-]. There is a positive salt effect. The active species and a plausible mechanism involing free redical have been proposed. All the experimental phenomena can be explained by the rate equation derived from the mechanism. The rate constants of rate-determing step together with the activation parameters have also been evalvated.
出处
《河北大学学报(自然科学版)》
CAS
1996年第1期91-94,共4页
Journal of Hebei University(Natural Science Edition)
基金
河北省自然科学基金
关键词
二过碲酸合铜
氧化还原反应
丙酮酸钾
动力学
Ditellurato-cuprate(Ⅲ)
Redox reaction
Potassium pyrurate
Kinetics and mechanism