Kinetics modeling for the mixed reforming of methane over Ni-CeO2/MgAl2O4 catalyst

doi:10.1016/S1003-9953(10)60148-X

Journal of Natural Gas Chemistry

Volume 20, Issue 1, January 2011, Pages 9-17

https://doi.org/10.1016/S1003-9953(10)60148-X Get rights and content

Abstract

Kinetics model was developed for the mixed (steam and dry) reforming of methane, which is useful for the control of H₂/CO ratio. The equilibrium constants of reaction rate were determined using the experimental equilibrium data at different reaction temperatures, while the forward reaction rate constants were estimated using the experimental data under non-equilibrium (high inert fraction and high space velocity) conditions. The comparison between calculated and experimental data clearly showed that the developed model described satisfactorily, and further analysis using the parametric sensitivity determined the wall temperature and CO₂ fraction in the feed gas as effective parameters for the manipulation of CH₄ conversion and H₂/CO ratio of synthesis gas under the equilibrium condition. Meanwhile, the inert fraction, rather than the residence time, was selected as additional parameter under non-equilibrium condition.

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This procedure is also used for the tri-reforming process which is presented in the next section. In this research, a kinetic model for the combined reforming by a Ni-CeO2/MgAl2O4 catalyst [28,29] is employed to predict the results for the syngas synthesis from bi-reforming reactions. The kinetic equations of this model are given by Equations B.1 - B.10 while the kinetic parameters are presented in Table B1.
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: This work was supported by the Energy Efficiency & Resources Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea Government Ministry of Knowledge Economy (No. 2006CCC11P011B-21-2-100) and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2010-0003380).

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Kinetics modeling for the mixed reforming of methane over Ni-CeO2/MgAl2O4 catalyst

Abstract

Appl Catal A

Chem Eng Sci

Int J Hydrogen Energy

Int J Hydrogen Energy

Catal Today

Chem Eng Sci

Appl Catal A

Chem Eng Sci

Chem Eng J

J Power Sources

Appl Catal A

Chem Eng J

Kinetics modeling for the mixed reforming of methane over Ni-CeO₂/MgAl₂O₄ catalyst