The trade-off relationship between permeability and selectivity as well as plasticization issues have largely impeded the advancement of membrane technology. Mixed-matrix-membranes (MMMs) with the incorporation of fillers into the polymer matrix is one promising method to deal with these challenges by carefully tuning their chemical properties. Compared with nanoparticles, the counterpart of nanosheet has a larger external surface area with a tendency to have closer contact with a polymer matrix to form a defect-free membrane at higher loading. This work successfully synthesized a high aspect ratio (30/1) of KAUST-8 nanosheets with high CO 2 uptake (60 cm 3 /g). This enables an optimal loading of 30 wt.% in the CO 2 -attractive crosslinked poly(ethylene oxide) (XLPEO) membrane and results in the simultaneously enhanced CO 2 permeability and CO 2 /N 2 selectivity with 280 % and 30 % up, respectively in the mixed gas permeation measurements (50/50 vol.). The resultant membrane performance surpassed the 2008 Robeson upper bound. Meanwhile, the stabilized MMM performance of up to 6 bar and high thermal stability of up to 350 °C bring extra benefits to the KAUST-8-based XLPEO membrane for post-combustion flue gas treatment.
In the petrochemical industry, the separation of C4 olefins is crucial but a challenging and energy-intensive process. In this study, two fluorinated anion-pillared hybrid ultramicroporous materials (HUMs), namely KAUST-7 (NbOFFIVE-1-Ni) and KAUST-8 (AlFFIVE-1-Ni), were explored for the efficient separation of ternary C4 olefin mixtures (C 4 H 6 /n-C 4 H 8 / iso -C 4 H 8 ) via gate-opening and size-sieving effects. KAUST-7, with a narrow and flexible pore window that completely excludes iso -C 4 H 8 , but allows for the absorption of C 4 H 6 and n-C 4 H 8 through gate-opening effects, with a preferential adsorption of C 4 H 6 due to its easier access to the channel. KAUST-8, on the other hand, with a larger pore window size and the strong H-bond interactions between the electronegative fluorine atoms from inorganic anion pillar and the C4 olefin molecules, efficiently separates iso -C 4 H 8 from C4 olefins, as the adsorption of both C 4 H 6 and n-C 4 H 8 is significantly enhanced while iso -C 4 H 8 retains much lower adsorption capacity. The relationship between the structures and separation properties of these materials is discussed, providing insight into the development of efficient separation materials. Fixed bed breakthrough experiments verify the excellent separation performances of KAUST-7 and KAUST-8 for C 4 H 6 /n-C 4 H 8 / iso -C 4 H 8 , highlighting their potential for industrial applications.
危险品化学品经营许可证（带存储）