Monte carlo and molecular dynamics simulations of clay mineral systems

Abstract

This chapter is focused on reviewing molecular dynamics and Monte Carlo simulations of greenhouse gases’ interactions with swelling clay minerals. This chapter unfolds with the results of simulations on stepwise expansion of interlayer in hydrated montmorillonite. Next, an overview of the simulation data on carbon dioxide intercalation in clays is given with respect to structural changes, transport properties, thermodynamics, spectroscopic characteristics, sorption behavior at the basal clay surfaces, and surface wettability changes in CO2-brine-mineral systems. Effects of the chemical nature of interlayer ions, as well as charge density and its distribution within clay layers on carbon dioxide/water intercalation and interaction with clay surfaces, are discussed. Then, results of methane interaction with hydrated swelling clays are presented. The discussion is centered around the formation of gas hydrate phase in the interlayer under suitable pressure and temperature conditions. Dynamic nature of hydrate cages encapsulating methane molecules is considered together with a mechanism of their formation in interlayer. A shift of the equilibrium pressure and temperature conditions in comparison with bulk phase is attributed to distortion of hydrate lattice in clay and to finite pore space. Finally, intercalation of the carbon dioxide/methane molecules in interlayer is reviewed through competitive adsorption of the binary mixture on clay surfaces.