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- ItemSomente MetadadadosSimulações Computacionais De Sistemas Absorvedores De Gases(Universidade Federal de São Paulo (UNIFESP), 2017-08-28) Cardoso, Piercarlo Fortunato [UNIFESP]; Siqueira, Leonardo Jose Amaral De [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)n this work, molecular dynamics simulations were employed in order to obtain physicochemical properties of solvation of the H2S, CO2 and CH4 gases in the ionic liquid butyltrimethylammonium bis(trifluoromethylsulfonyl)imide (IL), in the polymer poly (oxyethylene) (PEO) and in the mixing of the ionic liquid with the polymer. From the values of free energy of solvation (ΔGsol) of the gases in the three different systems were estimated the values of Henry's Law constant (KH) for CO2, H2S and CH4. Regardless the absorption system, the solubility of H2S was always greater than that of CO2, which in turn was more soluble than CH4. Among the systems, PEO showed the greatest solubility and interaction with the gases. In the study of bulk dynamic properties, the gas diffusion coefficients (D) were higher in the system with lower gas-absorber interactions. From the diffusion coefficients and of solubilities, the permeabilities of the gases in the systems were estimated. The H2S gas has been shown to be the most permeable in all three systems, while CH4 is the least permeable. For the study of the interface properties, it was observed by the density profiles that H2S has higher density inside the liquid phase. The existence of peaks in the density profiles at the liquid-gas interfaces evidences the adsorption layer of the gases. Potentials of mean force calculated from the density profiles showed the existence of valleys at the liquid-gas interfaces, whose depths followed the order: H2S > CO2 > CH4. The depth of the valleys presented correlation with the residence time of the gas at the surface of the liquid, that is, the deeper the valley, the longer the residence time of the gas at the interface. It was also observed a correlation between the residence time at the interface with the rate of absorbed gas molecules by the system. Therefore, the residence time and absorption kinetics of the molecules follow the order: H2S > CO2 > CH4. In the comparison between the systems, the PEO was the system that presented the highest solubility and highest rates of gas absorption.