Adsorption of propane and propylene in zeolitic imidazolate framework ZIF-8 pore: periodic SCC-DFTB method

Abstract

Adsorptions of propane and propylene in the ZIF-8 pore, were studied using periodic SCC-DFTB method. Six and eleven adsorption configurations for propane and propylene molecules in the ZIF-8 pore, were respectively found. The adsorption energies based on the most stable configurations of propane (− 1.38 kcal/mol) and propylene (− 1.25 kcal/mol) in the ZIF-8 pore were obtained. Due to adsorption abilities of the ZIF-8 pore which can adsorb propane better than propylene, the ZIF-8 therefore differentiate diffusion flux of propane and propylene via hexagonal aperture. These results agree with ability of the ZIF-8 pore to separate propane/propylene mixture based on the principle of gas–solid partition. All the adsorption configurations of propane and propylene molecules and their adsorption energies are reported.