Revisiting the Aluminum Trimesate-based MOF (MIL-96): from Structure Determination to the Processing of Mixed Matrix Membranes for CO2 Capture.
Abstract
A microporous Al trimesate-based Metal Organic Framework (MOF), denoted MIL-96(Al), was
selected as a porous hybrid filler for the processing of Mixed Matrix Membranes (MMMs) for
CO2/N2 post combustion separation. First, the structural model of MIL-96(Al) initially reported was
revisited using a combination of synchrotron-based single crystal X-ray diffraction (XRD), solid
state 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, were
prepared. Then, a combination of in situ IR spectroscopy, single gas and CO2/N2 co-adsorption
experiments, calorimetry and molecular simulations revealed that MIL-96(Al) nanoparticles show a
relatively high CO2 affinity over N2 owing to strong interactions between CO2 molecules and
several 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 the
processing of homogeneous and defect-free MMMs with a high MOF loading (up to 25 wt%) that
outperform pure polymer membranes for CO2/N2 separation.
Domains
Material chemistry| Origin | Files produced by the author(s) |
|---|