Stationary fronts due to weak thermal effects in modelsof catalytic oxidation

• Published in: The Journal of chemical physics Vol. 123; no. 6; pp. 064708 - 064708-6
• Main Authors: Sheintuch, Moshe, Nekhamkina, Olga
• Format: Journal Article
• Published: American Institute of Physics 16.08.2005
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.2000232

We analyze the possible existence of an infinite number of stationary front solutions in a microkinetic model of a catalytic reaction coupled with weak enthalpy effects in the domain of kinetics bistability. The kinetic model incorporates three steps: dissociative oxygen adsorption, reactant adsorption and desorption, and surface reaction. The infinitude of stationary front solutions emerges due to the lack of intercrystallites communication of surface species in supported catalysts; thermal conductions and gas-phase diffusion are the only means of interaction. Incorporation of surface species diffusion leads to a very slow front motion. We complement this analysis with simulations of stationary states on one- (wire and ring) and two-dimensional (disk) systems which may be subject to control or to fluid flow. These results account for certain experimental results and may have implications for various technological problems.