Reaction kinetics of ammonia decomposition over La-CoMoNx/CNTs catalyst
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摘要: 以La-CoMoNx/CNTs为催化剂,对氨分解制氢反应的本征动力学进行了研究。考察了N2浓度、H2浓度、NH3浓度以及反应温度对反应速率的影响。采用幂指数方程描述反应动力学,确定了本征动力学参数,推导出了本征动力学方程,得到反应的活化能为93.948 kJ/mol。同时对其反应机理进行了探讨,认为La-CoMoNx/CNTs催化剂上氨分解反应遵循Temkin-Pyzhev机理,即表面氮原子的结合脱附为反应的速率控制步骤。Abstract: The reaction kinetics of ammoniade composition over La-CoMoNx/CNTs catalyst were studied. The effect of N2 concentration, H2 concentration, NH3 concentration and reaction temperature on the rate of ammonia decomposition were investigated. According to the experimental data, the correlative kinetic parameters were determined based on an exponential equation. The intrinsic kinetic equation was obtained. The activation energy of the reaction was 93.948 kJ/mol. The reaction mechanism was also discussed. The reaction rate of ammonia decomposition over La-CoMoNx/CNTs was controlled by the combination desorption of nitrogen on the surface of the catalyst.
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Key words:
- supported metallic nitride /
- catalysis /
- ammonia decomposition /
- hydrogen production /
- reaction kinetic
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