Combining spectroscopic and transient kinetic techniques provides access to the identification and quantification of active sites and corresponding turnover frequencies of catalyzed reactions [1]. Ab initio calculated rate coefficients combined with network generation codes allow so-called microkinetic models accounting for all relevant elementary steps of complex reaction networks. Computational Fluid Dynamics (CFD) account for the scale-dependent transport of mass, energy and momentum and, hence, renders the design of an industrial process based on the intrinsic chemical kinetics possible. These theoretical and experimental achievements cannot be a substitute for the insights provided by the analysis of a catalytic cycle in terms of a limited number of kinetically significant steps [2]. We analyse the kinetics of a single-path reaction represented as a closed sequence of two steps [3]. We discuss some examples of chemical looping processes providing, in contrast to catalytic technology, the possibility to perform the steps of a closed sequence at different conditions.

结合光谱和瞬态动力学技术可以识别和量化催化反应的活性位点和相应的转换频率 [1]。从头算计算的速率系数与网络生成代码相结合，允许所谓的微动力学模型解释复杂反应网络的所有相关基本步骤。计算流体动力学 (CFD) 解释了质量、能量和动量的尺度相关传输，因此，使基于内在化学动力学的工业过程设计成为可能。这些理论和实验成果不能替代通过有限数量的动力学重要步骤分析催化循环所提供的见解 [2]。我们分析了表示为两个步骤的封闭序列的单路径反应的动力学 [3]。我们讨论了一些化学循环过程的例子，与催化技术相比，它提供了在不同条件下执行封闭序列步骤的可能性。