Computational study of CO2 absorption in aqueous and non-aqueous solutions using MEA

Chemical absorption using Ethanolamine to capture CO2 is considered to be an effective way to cover the large reduction of the greenhouse gas emissions. As the absorption capacity is different between aqueous and nonaqueous solutions, in this work, the reaction processes about monoethanolamine (MEA) absorbing CO2 in aqueous and non-aqueous (take methanol as the medium) solvation effect without solvent molecular are studied using density functional theory (DFT), respectively. The result shows that the reaction mechanism is same both in aqueous and non-aqueous solutions and a two-step reaction process can demonstrate it well. The main effect of the different solvent on the reaction is the relative energy of the optimized configurations. The energy shows that stable configurations have lower relative energy in methanol than in water, which demonstrates that the configurations are more stable in non-aqueous solutions than those in aqueous solutions. (C) 2013 The Authors. Published by Elsevier