(100d) Kinetic Monte Carlo Simulations of the Fischer-Tropsch Reaction

Kinetic Monte Carlo (kMC)[1] simulations are the most relevant tool to accurately study the kinetics of the surface catalytic processes such as the Fischer-Tropsch (FT) sysnthesis. Quantum mechanically calculated activation barriers[2] and rate constants of the elementary processes such as adsorption, diffusion, desorption etc. are related to their actual occurance and therefore to the overall kinetics by the kMC methods. In this work, kMC simulations are used to perform a detailed analysis of the effect of barriers and the thermodynamics of the intermediates in the methanation reaction. We will present models on methanation representataive of different surfaces of transition metals as Ru or Co. We present also the trends in the methanation yield rate and the surface compositions as a function of temperatures and CO activation energies. We then proceed to two different models which incorporate the C-C coupling in the formation of ethylene and ethane respectively. We observe that the reaction rates are very sensitive wth respect to activation energies of CO and rate of oxygen removal.
References:
1. Tonek Jansen, Kinetic Monte Carlo, pgs 183-197, Computational Methods in Catalysis and Materials Science. (Eds) Rutger A. van Santen and Phillipe Sautet, WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, 2009.
2. I. M. Ciobica, G. J. Kramer, Q. Ge, M. Neurock, and R. A. van Santen Mechanisms for Chain Growth in Fischer-Tropsch Synthesis over Ru(0001), Journal of Catalysis 212, 136-144 (2002).