Simulation of adsorption and diffusion behaviors of H2O and O2 in low-rank coal pores

In this paper, Materials Studio software was used to construct 2–7 nm cylindrical pore models to study the adsorption and diffusion behaviors of H2O and O2. The results show that H2O is adsorbed in multiple layers or clusters in micro-mesoporous pores, while O2 is adsorbed in single layer·H2O occupied the adsorption site of O2, resulting in a decrease in the adsorption capacity of O2 by 5.44%∼31.38%. The diffusion coefficients of H2O and O2 are both on the order of 10−8 m2/s, but H2O will preferentially bind to high-energy sites, promoting the diffusion of O2.