Effect of Ionic Liquid Confinement on Gas Separation Characteristics

Work in our laboratory has focused for a number of years on examining the potential of room-temperature ionic liquids for post-combustion carbon capture processes. Results from studies of carbon dioxide solubility, diffusivity, and permeation across supported ionic liquid membranes have raised questions about the impact of a solid interface on the of ionic liquids. In this paper, we report results from measurements of carbon dioxide uptake into ionic liquids confined within a ceramic nanoporous film and compare carbon dioxide solubility and diffusivity to values measured with bulk phase ionic liquids. Results show that both Solubility and diffusivity are enhanced in confined ionic liquids when compared to values observed m unconfined liquids. These observations have implications for gas separation processes involving supported ionic liquid membranes.