| 초록 |
Here, we report the enhanced organic solvent resistance of SIFSIX-3-Ni by characterizing their crystallinity and gas adsorption properties after exposure to organic solvents. SIFSIX-3-Ni microparticles were incorporated into polysulfone (PSF) matrix to prepare mixed matrix membranes (MMMs) for CO2/CH4 separation. PSF/SIFSIX-3-Ni MMMs with loading up to 30% were successfully prepared with the aid of the weak interaction between sulfonate groups in PSF and the fluorine atoms of SIFSIX-3-Ni. Interestingly, the CO2 permeability of PSF/SIFSIX-3-Ni MMMs monotonically decreased with increasing CO2/CH4 selectivity as the SIFSIX-3-Ni concentration increased. Monte Carlo simulations suggest that the strong Coulombic interactions between SIFSIX-3-Ni and CO2 significantly increased the free energy barrier for CO2 over CH4, leading to a reduction in the CO2/CH4 diffusive selectivity of MMMs. Unlike diffusivity, the CO2 solubility of PSF/SIFSIX-3-Ni MMMs increased with increasing SIFSIX-3-Ni contents due to the strong interaction between SiF62- of SIFSIX-3-Ni and CO2, significantly enhancing the CO2/CH4 adsorptive selectivity. |
