Adsorption Behavior of Methane on Kaolinite

Abstract

In this work, the adsorption behaviors of CH4 in slit-like kaolinite pores were investigated using the grand canonical Monte Carlo method. The research results show that the isosteric heat of adsorption of CH4 decreases with increasing pore size and that CH4 adsorption on kaolinite can be characterized as physical adsorption. The potential energy between CH4 and kaolinite was found to decrease with increasing pressure or decreasing pore size, indicating that the adsorption sites of CH4 changed from higher-energy adsorption sites to lower-energy adsorption sites. The CH4 adsorption capacity decreased with increasing pore size in mesopores. With increasing temperature, the isosteric heat of adsorption of CH4 decreased, and the adsorption sites of CH4 changed from higher-energy adsorption sites to lower-energy adsorption sites, resulting in a decrease of the CH4 adsorption capacity. As a result of van der Waals force interactions, Coulomb force interactions, and hydrogen-bonding interactions, the water molec...