Monte Carlo simulations of sorption and diffusion of isobutane in silicalite

We report kinetic Monte Carlo (KMC) and configurational-biased Monte Carlo (CBMC) simulations of isobutane adsorbed in zeolite silicalite. The CBMC simulations provide evidence for the presence of repulsive interactions between molecules adsorbed at adjacent intersection and straight-channel sites. KMC simulations show that even weak repulsive interactions have a strong influence on the diffusivities at higher loadings and therefore could serve as a possible explanation for the experimentally observed change of the apparent activation energy of self- and Maxwell-Stefan diffusion coefficients in this regime. (C) 2001 Elsevier Science B.V. All rights reserved.