Coke formation over a nickel catalyst under methane dry reforming conditions:: Thermodynamic and kinetic models
Coke formation over a nickel catalyst under methane dry reforming conditions:: Thermodynamic and kinetic models
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DOI：
10.1021/ie0496333
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发表时间：
2005-07-06
影响因子：
4.2
通讯作者：
de Lasa, HI
中科院分区：
文献类型：
--
作者：
Ginsburg, JM;Piña, J;de Lasa, HI
在20wt%Ni/USY-沸石上研究甲烷的CO2重整，并且更具体地，使用焦炭形成的热力学分析作为在干重整条件下存在的焦炭现象的动力学建模的基础。两个热力学参数，α和β，比较的CH，分解和CO分解反应的平衡常数和定义，以确定是否有利于焦炭的形成。该热力学分析阐明了CO加氢反应对催化剂上积炭量的重要性。一个动力学模型与负的整体顺序之一，相对于一氧化碳的分压，被认为是最准确的预测焦炭形成的速率。这种类型的动力学强烈地表明，在允许的热力学条件下进行焦化反应需要三个相邻的游离催化剂位点。
The CO2 reforming of methane is studied over a 20 wt % Ni/USY-zeolite, and more specifically, a thermodynamic analysis of the formation of coke is used as a basis for the kinetic modeling of coke phenomena that exist under dry reforming conditions. Two thermodynamic parameters, alpha and beta, are compared to the equilibrium constants for the CH, decomposition and the CO disproportionation reactions and defined to determine whether coke formation is favored. This thermodynamic analysis elucidates the significance of the CO disproportionation reaction on the amount of coke deposited over the catalyst under consideration. A kinetic model with negative overall order of one, with respect to the partial pressure of carbon monoxide, is found as the most accurate prediction of the rate of coke formation. This type of kinetics strongly suggests the requirement of three adjacent free catalyst sites for the coking reaction to proceed under allowable thermodynamic conditions.