J. Phys. IV France 10 (2000) Pr7-143-Pr7-146
Dynamics of alkane mixtures in silicalite poresL.N. Gergidis1, D.N. Theodorou1 and H. Jobic2
1 Department of Chemical Engineering, University of Patras, and Institute of Chemical Engineering and High Temperature Chemical Processes, 26500 Patras, Greece
2 Institut de Recherches sur la Catalyse, CNRS, 2 avenue Albert Einstein, 69626 Villeurbanne, France
The transport of n-butane – methane mixtures in silicalite has been studied at 200 K using molecular dynamics simulations and quasi-elastic neutron scattering experiments. The dependence on the wave vector of the half-width at half-maximum of the incoherent dynamic structure factor is indicative of a jump diffusion process. Distributions of the jump lengths of methane using a coarse-grained jump model have shown that the jump lengths are widely distributed between 0 and 15 Å, the mean jump length being a decreasing function of the loading. Self-diffusivity values calculated from the dynamics simulations are in excellent agreement with the experimental measurements from quasi-elastic neutron scattering.
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