Surface Tension of Binary and Ternary Systems Containing Monoethanolamine (MEA), Water and Alcohols (Methanol, Ethanol, and Isopropanol) at 303.15 K

Solutions containing alkanolamines or amines are broadly used for the removal of acidic compounds such as hydrogen sulfide (H2S) and carbon dioxide (CO2) from natural gas flows. In this study, the surface tension of three binary mixtures containing monoethanolamine (MEA) and alcohol (methanol, ethanol, or isopropanol) and three ternary systems containing MEA, water, and alcohol (methanol, ethanol, or isopropanol) were determined in the whole composition range at 303.15 K and ambient pressure by means of the Du Nouy ring method. From these data, the composition dependence of the surface tension (sigma) and surface tension deviation (Delta sigma) of binary mixtures was correlated using the FLW equation (proposed by Fu et al.) and the MS equation (proposed by Myers and Scott), respectively. Then, the surface tension data of three ternary mixtures were correlated with a polynomial based on the Scatchard model. Also, the surface tension data of three ternary mixtures were predicted based on the FLW model. The results show a good agreement between the predicted and measured values, as well as the applicability of the FLW model in these ternary mixtures. Finally, the isoline curves of surface tension and surface tension deviation versus mole fraction of components for the ternary mixtures are plotted and discussed.