Molecular dynamics simulations were performed in order to study the influence of the zeolite structure upon molecular migration in the zeolitic void space. The migration of methane in various zeolitic environments was examined by using the all-silica polymorphs of zeolite EU-I, mordenite and silicalite. Diffusion simulations of ethane and propane in silicalite were also carried out (table 41).
Mobility of Adsorbed Species in Zeolites: Methane, Ethane, and Propane Diffusivities. A.K.Nowak, C.J.J.Den Ouden, S.D.Pickett, B.Smit, A.K.Cheetham, M.F.M.Post, J.M.Thomas: Journal of Physics Chemistry, 1991, 95[2], 848-54
Table 41
Diffusion in Silicalite
Diffusant | Direction | D(m2/s) |
methane | x | 4.40 x 10-9 |
methane | y | 1.33 x 10-8 |
methane | z | 1.10 x 10-9 |
ethane | x | 3.00 x 10-9 |
ethane | y | 8.80 x 10-9 |
ethane | z | 2.40 x 10-9 |
propane | x | 3.00 x 10-9 |
propane | y | 9.00 x 10-9 |
propane | z | 3.00 x 10-10 |