Résumé
A microporous Al trimesate-based Metal Organic Framework (MOF), denoted MIL-96(Al), wasselected as a porous hybrid filler for the processing of Mixed Matrix Membranes (MMMs) forCO2/N2 post combustion separation. First, the structural model of MIL-96(Al) initially reported wasrevisited using a combination of synchrotron-based single crystal X-ray diffraction (XRD), solidstate Nuclear Magnetic Resonance (NMR) spectroscopy and Density Functional Theory (DFT)calculations. In a second step, pure MIL-96 (Al) crystals differing by their size and aspect ratio,including anisotropic hexagonal platelets and nanoparticles of about 70 nm in diameter, wereprepared. Then, a combination of in situ IR spectroscopy, single gas and CO2/N2 co-adsorptionexperiments, calorimetry and molecular simulations revealed that MIL-96(Al) nanoparticles show arelatively high CO2 affinity over N2 owing to strong interactions between CO2 molecules andseveral adsorption sites such as Al3+ Lewis centers, coordinated water and hydroxyl groups. Finally,the high compatibility between MIL-96(Al) nanoparticles and the 6FDA-DAM polymer allowed theprocessing of homogeneous and defect-free MMMs with a high MOF loading (up to 25 wt%) thatoutperform pure polymer membranes for CO2/N2 separation.