Molecular dynamics simulation of the interaction of ethanol-water mixture with a Pt surface

Kholmirzo Kholmurodov, Ermuhammad Dushanov, Kenji Yasuoka, Hagar Khalil, Ahmed Galal, Sameh Ahmed, Nasser Sweilam, Hatem Moharram

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DOI: 10.4236/ns.2011.312126                

Abstract

An analysis of the molecular dynamics of ethanol solvated by water molecules in the absence and presence of a Pt surface has been performed using DL_POLY_2.19 code. The structure and diffusion properties of an ethanol–water system have been studied at various temperatures from 250 to 600 K. We have measured the self-diffusion coefficients of the 50:50% ethanol–water solution; in the absence of a Pt surface our results show an excellent agreement–within an error of 7.4% – with the experimental data. An increase in the self-diffusion coefficients with the inclusion of a Pt surface has been observed. The estimation of the diffusion coefficients of both water and ethanol in the presence of a Pt surface shows that they obey the Arrhenius equation; the calculated activation energies of diffusion of ethanol and water are 2.47 and 2.98 Kcal/mole, respectively. The radial distribution function graphs and density profiles have been built; their correlations with the self-diffusion coefficients of both ethanol and water molecules are also illustrated.

Keywords

Molecular Dynamics Simulations; Ethanol Molecule; Water Active Solvent; Diffusion Coefficient; Pt Surface; RDF Graphs

Conflicts of Interest

The authors declare no conflicts of interest.

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