期刊论文

Kinetics and Mechanism of Oxalic Acid Oxidation by Nitric Acid Catalyzed by Mn(Ⅱ)

Xia, L.-S.

中文

应用化学

1000-0518

2021

38

6

685-692

10.19894/j.issn.1000-0518.200320

本校为第一机构

为明确反应机理和反应历程,优化反应工艺条件,开展了在硝酸体系中以草酸为还原剂、Mn~(2+)为催化剂催化硝酸氧化草酸的动力学研究。通过考察草酸浓度、硝酸浓度等反应条件对反应过程的影响,确定了该反应的初始动力学速率方程为:-dc(H_2C_2O_4) /dt = kc~(0.7840)(H_2C_2O_4) c~(0.3192)(HNO_3),在393 K时,反应速率常数k = 3.0×10~(-3)(mol /L)~(-0.1032) /min。研究了Mn~(2+)和亚硝酸钠浓度对反应速率的影响,结果表明,Mn~(2+)浓度在0.008 ~ 0.020 mol /L范围内,Mn~(2+)的反应级数为0.6742,Mn~(2+)和亚硝酸钠浓度的增加对初始草酸消耗速率有促进作用,并在此基础上推测了可能的反应机理,认为Mn~(...

A kinetic study on the oxidation of oxalic acid by nitric acid using Mn2+ as the catalyst was carried out to clarify the reaction mechanism and reaction process, and optimize the process conditions. By investigating the influence of concentrations of oxalic acid and nitric acid on the reaction process, the initial kinetic rate equation of the reaction is obtained: -dc(H2C2O4)/dt=kc0.7840(H2C2O4)c0.3192(HNO3), and the reaction rate constant is k=3.0×10-3 (mol/L)-0.1032/min at 393 K. The results show that when the Mn2+ concentration is in the ra...