Design of 2D materials for selective adsorption: a comparison between Monte Carlo simulations and direct numerical integration

Understanding the behaviour of fluids in confinement is essential to predict adsorption selectivity and develop adsorbents that can address challenging separations, such as ethane/ethylene mixtures. In this work we show that adsorption selectivity for an ethane/ethylene mixture can be predicted from direct numerical integration of the solid-fluid interaction potential because fluid-fluid interactions are negligible when compared to solid-fluid interactions, and adsorption sites are indistinguishable in pure component and mixture simulations. We present a comprehensive analysis of the density and orientation distributions in the pores as a function of pore size and pressure, providing tools that can be used for the design of 2D materials for the selective adsorption of gases.