| Global warming mainly caused by carbon dioxide (CO2) emissions can be reduced by its capture and/or sequestration from post combustion flue gases via economically viable processes such as gas separation technology using polymer-based mixed-matrix membranes (MMMs). A series of MMMs were fabricated by incorporating various hydrothermally stable microprorous zeolitic imidazole frameworks (ZIFs: ZIF-300, ZIF-301, ZIF-302) nanocrystals, carbon nanotubes (CNTs) and/or their combinations into glassy polymers via solution-casting method. Different loadings of CNTs and/or ZIFs nanocrystals were incorporated into polysulfone (PSF) matrix to find the separation effectiveness of MMMs to remove CO2 from dry and wet CO2/N2 gaseous mixtures. The flexible MMMs rendered homogeneous dispersion of nanofillers, improved polymerfiller interfacial adhesion, and hydrothermally stable structure as characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA). Gas sorption analyses along with dry and wet gas permeation tests helped to determine the optimized CO 2 permeability as well as CO2/N2 permselectivity of the MMMs. The permeation features of MMMs were slightly improved under humid conditions as compared to dry ones. |
