(288e) Preparation and Characterization of Fluoropolymeic Microcapsules for Gas Separation Applications

Fabrication of microcapsules with permeable shells has been an active research topic for the past two decades. A simple one-step approach for encapsulation of ionic liquid absorbents within a polymeric shell of fluoropolymers was developed. Using this approach, we can benefit from the advantages of liquid solvent sorbent, such as high selectivity and high capacity, and the enhanced specific mass transfer area, provided by the microcapsules. The effect of different parameters including choice of solvent, non-solvent pair, the molecular weight of polymers, dope solution concentration and different solvents such as acetone, triethyl phosphate (TEP), and dimethylacetamide (DMAc) were systemically investigated. Microcapsules with desired sizes and porosity were fabricated. By adjusting the experimental parameters, the mean diameters of these microcapsules were tuned in between 700 to 2000 µm. The cross-sectional scanning electron microscopy images of the shells, showed that the thickness was in between 60 to 160 µm, translating into the void density values of more than 75%. Moreover, using different non-solvent systems, roughness and surface structure of the capsules were adjusted. The physical stability and chemical resistance of these polymeric shells allow for these capsules to be used in a variety of processes such as gas sorption. Microcapsules, loaded with ionic liquid, were fabricated and tested for carbon dioxide adsorption from gaseous mixture.