Molecular dynamics simulations of the adsorption and diffusion behavior of pure and mixed alkanes in silicalite

• Published in: Microporous and mesoporous materials 2005-10, Vol.85 (1), p.143-156
• Main Authors: Hussain, I., Titiloye, J.O.
• Format: Article
• Language: English
• Subjects: Adsorption; Alkane mixtures; Chemistry; Colloidal state and disperse state; Diffusion; Exact sciences and technology; General and physical chemistry; Ion-exchange; Molecular dynamics; Porous materials; Surface physical chemistry; Zeolites; Zeolites: preparations and properties
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2005.06.017

The adsorption and diffusion of mixed hydrocarbon components in silicalite have been studied using molecular dynamic simulation methods. We have investigated the effect of molecular loadings and temperature on the diffusional behavior of both pure and mixed alkane components. For binary mixtures with components of similar sizes, molecular diffusional behavior in the channels was noticed to be reversed as loading is increased. This behavior was noticeably absent for components of different sizes in the mixture. Methane molecules in the methane/propane mixture have the highest diffusion coefficients across the entire loading range. Binary mixtures containing ethane molecules prove more difficult to separate compared to other binary components. In the ternary mixture, however, ethane molecules diffuse much faster at 400 K in the channel with a tendency to separate out quickly from other components.