Thermal Desorption in Pure Hexane and Hexane/Butane Mixtures on Graphite

نویسنده

  • Cary L. Pint
چکیده

The results of an extensive study of desorption in hexane (monolayer and submonolayer) and hexane/butane mixtures initially adsorbed onto the graphite basal plane is presented. Molecular dynamics (MD) simulations are utilized to carry out atomistic simulations at temperatures 300≤T≤700 for all three cases studied. Results from submonolayer and monolayer hexane indicate that the desorption energy needed for the system to proceed with the desorption process is independent of the system’s coverage, which is in good agreement with experimental results. It is also found that simulations of desorption of hexane/butane mixtures yield a high ratio of butane molecules being desorbed from the surface at lower temperatures (300 K), suggesting a strong dependence of the desorption barrier upon alkane chain length. The results are discussed and compared to previous experimental and theoretical results.

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تاریخ انتشار 2004