大学化学2016，Vol.31Issue(10)：84-88,5.DOI:10.3866/PKU.DXHX201603015
碳氧化反应速率常数与温度特殊关系的理论解释
Theoretical Explanation of the Special Temperature Dependence of Rate Constant for Oxidation of Carbon
孔令然 1张树永1
作者信息
- 1. 山东大学化学与化工学院，济南250100
- 折叠
摘要
Abstract
For oxidation of carbon in different temperature ranges, there is different temperature dependence of rate constant. The temperature dependence can be divided into two sections. The first section is mainly determined by the chemical adsorption of oxygen on the carbon surface, forming oxygen-containing surface complexes. The effect of temperature on adsorption equilibrium of oxygen results in the first increase and then decrease of rate constant with increasing temperature. For the second section, it is mainly influenced by gasification of carbon in carbon dioxide, in which desorption of the carboxyl group is the rate-determining step (r.d.s.). In this paper, a comparison among the formerly established mechanisms for carbon oxidation at high temperature was made and a simplified mechanism was put forward. The rate equation for the second section was deduced based on this new mechanism using r.d.s. approximation and pre-equilibrium approximation treatments. The deduced rate equation is in good accordance with the main experimental facts. Therefore, a satisfactory explanation is given for the unusual behavior of carbon oxidation.关键词
碳氧化反应/多相反应/吸附平衡/二氧化碳/反应机理Key words
Carbon oxidation/Heterogeneous reaction/Adsorption equilibrium/Carbon dioxide/Reaction mechanism分类
社会科学引用本文复制引用
孔令然,张树永..碳氧化反应速率常数与温度特殊关系的理论解释[J].大学化学,2016,31(10):84-88,5.
