Molecular Simulations of Acid Gas Absorption into Aqueous Solvents

Molecular simulations predict the thermodynamic and transport properties by computing the interactions between the molecules in a system. These simulations offer practical alternatives to address challenges arising from experimental limitations in measuring Vapor-Liquid Equilibria (VLE) of acid gases at very low partial pressures and the diffusivities in reactive solutions.
In this thesis, we investigated how force field-based molecular simulations can be used to compute reaction equilibria and transport properties, relevant for absorption-based CO₂ and H₂S removal. We introduced novel features to the Brick-CFCMC code and developed a versatile chemical reaction equilibria solver, called CASpy, to compute the concentration of species in any reactive liquid-phase absorption system, including CO₂ and H₂S absorption in aqueous alkanolamine solutions. We also investigated transport properties of CO₂ and H₂S in aqueous solutions of two commonly used alkanolamines, MEA and MDEA.