Mechanistic importance of intermediate N2O + CO reaction in overall NO + CO reaction system. I: Kinetic analysis
Mechanistic importance of intermediate N2O + CO reaction in overall NO + CO reaction system. I: Kinetic analysis
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DOI：
10.1016/0021-9517(92)90021-9
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发表时间：
1992-11
影响因子：
7.3
通讯作者：
B. Cho
中科院分区：
文献类型：
--
作者：
B. Cho
为了研究贵金属尾气催化剂上CO还原NO过程中N2O + CO反应作为中间反应步骤的机理重要性，我们基于基元表面过程理论分析了NO + CO反应的稳态动力学。拟线性化的非线性NO + CO反应系统，通过确定一个关键的动力学参数，使我们能够开发一套完整的系统，其中包括中间N2O + CO反应步骤的解析解。动力学分析表明，N_2O + CO反应作为中间反应与单独反应的速率有很大差异。结果表明，作为NO + CO反应体系中的中间反应的N2O + CO反应的速率可以比孤立的N2O + CO反应快两到三个数量级，已知孤立的N2O + CO反应与NO + CO反应相比非常慢。这使得中间N2O + CO反应的速率与NO + CO反应的速率一样快或甚至更快，表明前一反应可以对三元催化转化器中发生的CO还原NO的动力学做出主要贡献。
To investigate the mechanistic importance of the N2O + CO reaction as an intermediate reaction step during the reduction of NO by CO occurring on noble metal exhaust catalysts, we have analyzed theoretically the steady-state kinetics of the NO + CO reaction based on elementary surface processes. Quasilinearization of the nonlinear NO + CO reaction system by identifying a critical kinetic parameter has enabled us to develop a complete set of analytical solutions for the system which includes the intermediate N2O + CO reaction step. The kinetic analysis based on this solution scheme shows a dramatic difference between the rate of the N2O + CO reaction as anintermediatereaction and that as anisolatedreaction. Results have revealed that the rate of the N2O + CO reaction as an intermediate reaction in the NO + CO reaction system can be two to three orders of magnitude faster than the isolated N2O + CO reaction, which is known to be very slow compared with the NO + CO reaction. This makes the rate of the intermediate N2O + CO reaction as fast as or even faster than the rate of the NO + CO reaction, suggesting that the former reaction can make a major contribution to the kinetics of the reduction of NO by CO occurring in three-way catalytic converters.