Thermodynamic analysis and dynamics simulation on reaction of Al₂O and AlCl₂ with carbon under vacuum

Abstract

The feasibility study of the AlCl(g) generated by Al₂O−AlCl₂−C system under vacuum was carried out by thermodynamic analysis and CASTEP package of the Material Studio program which was based on density functional theory (DFT) formalism. Thermodynamic calculations indicate that AlCl and CO molecules can be formed under conditions of temperature 1760 K and the pressure of 60 Pa. The interaction of Al₂O and AlCl₂ with C shows that the chemical adsorption of Al₂O and AlCl₂ does take place on C(001) crystal plane, and at the same time, new chemical bond is formed between Al atom in Al₂O and Cl atoms from one of the Al—Cl bonds in AlCl₂. The results, after 1.25 ps dynamics simulation, indicate that adsorbed AlCl molecules are generated and CO molecule will be formed in this system, and they will escape from C(001) surface after a longer period of dynamic simulation time. It means that the reaction of Al₂O and AlCl₂ with C can be carried out under given constraint condition.

Keywords

Ab initio molecular dynamics / carbothermic−chlorination (AlCl₂) reaction / thermodynamics / interaction / Al₂O

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