期刊论文

中文

核科学与工程

0258-0918

2022

42

3

677-683

10.3969/j.issn.0258-0918.2022.03.025

国家自然科学基金资助项目（22176083）； 湖南省自然科学基金资助项目（2021JJ30566）；

本校为第一机构

为明确Mn(Ⅲ)氧化破坏草酸的反应机理和反应历程,优化该反应的工艺条件,开展了动力学过程及机理研究。通过考察草酸浓度、Mn(Ⅲ)浓度和酸度等反应条件对反应历程的影响,确定了该反应的初始动力学速率方程为: -dc(Mn(Ⅲ))/dt = kc~(0.885 5)(H_2C_2O_4)c~( 0.727 4)(Mn(Ⅲ)),在温度为298.15 K时,速率常数k = 2.0 × 10~2(mol/L)~(-0.612 9)/min。研究了甲醇体系下Mn(Ⅲ)与草酸反应过程中产生的自由基,由此推测了Mn(Ⅲ)氧化破坏草酸过程的反应机理:Mn(Ⅲ)氧化破坏草酸的过程为单电子氧化过程,反应速度极快,能够迅速使草酸分解。

In order to clarify the reaction mechanism and process of the oxalic acid destroyed by Mn(Ⅲ)oxidation and optimize the reaction conditions,the kinetic process and mechanism were studied.By investigating the effects of the oxalic acid concentration,the Mn(Ⅲ)concentration and acidity on the reaction process,the initial kinetic rate equation of the reaction was determined as follows:-dc(Mn(Ⅲ))/dt=kc0.8855(H2C2O4)c0.7274(Mn(Ⅲ)),At298.15 K,the reaction rate constant is 2.0×102(mol/L)-0.6129/min.The free radicals produced by the reaction of Mn(Ⅲ...