Adsorption and Diffusion of Methane in Coal Slit Pores: Insights into the Molecular Level

Coal contains multi-scale pore structures, which determine the adsorption and diffusion of methane. To further reveal the effect of the pore structure from the molecular level, we construct the different slit pore models of coal and carry out a series of molecular simulations. The results show that the increase of slit pores increases the absolute adsorption capacity and isosteric heat of adsorption. The increased slit pores can promote the self-diffusion and transport diffusion of methane molecules. This research can provide a basis for the theory of the coal–methane interaction.