Microkinetic Modeling of the Fischer-Tropsch Synthesis over Cobalt Catalysts
Microkinetic Modeling of the Fischer-Tropsch Synthesis over Cobalt Catalysts
复制标题
DOI：
10.1002/cctc.201402662
复制
发表时间：
2015-01-01
期刊：
影响因子：
4.5
通讯作者：
Kraft, Markus
中科院分区：
文献类型：
--
作者：
Azadi, Pooya;Brownbridge, George;Kraft, Markus
本文对Co/γ-Al_2O_3催化剂上的费托合成反应进行了详细的微观动力学分析。实验在卡伯利转篮式间歇反应器中进行，初始H-2/CO比为1.8~2.9，温度为469~484K，初始压力为2 Mpa。提出了一个基于H-2辅助的CO活化途径的反应机理，它包括128个基元反应和85个自由参数，解释了实验结果。这些基本反应中的每一个都属于下列反应基团之一：吸附-解吸、单体形成、链生长、氢化-氢提取或水-气变换。基于准随机全局搜索和无梯度局部优化的两阶段参数估计方法被用来计算指前因子和激活能的值。利用从批量实验中获得的数据，能够有效地分析合成气转化不同阶段的主要反应。
We present a detailed microkinetic analysis of the Fischer-Tropsch synthesis on a Co/gamma-Al2O3 catalyst over the full range of syngas conversions. The experiments were performed in a Carberry spinning basket batch reactor at initial H-2/CO ratios between 1.8 and 2.9, temperatures of 469 and 484 K, and initial pressures of 2 MPa. A reaction mechanism based on the H-2-assisted CO activation pathway, which comprises 128 elementary reactions with 85 free parameters, was proposed to explain the experimental results. Each of these elementary re-actions belongs to one of the following reaction groups: adsorption-desorption, monomer formation, chain growth, hydrogenation-hydrogen abstraction, or water-gas shift. A two-stage parameter estimation method, based on a quasi-random global search followed by a gradient-free local optimization, has been used to calculate the values of pre-exponential factors and activation energies. The use of data obtained from batch experiments enabled an effective analysis of dominating reactions at different stages of syngas conversions.