Engineering structured MOF at nano and macroscales for catalysis and separation

Abstract

Here, we present for the first time the combination of the postfunctionalization of a MOF with its shaping as structured bodies. This study deals with the porous zinc carboxylimidazolate material known as SIM-1. A great advantage of this method is that the aldehyde moieties present on the structure walls allow organic modifications in the solid state, such as imine synthesis by condensation with primary amines to give the corresponding imino-functionalized SIM-2. We show that this postfunctionalization can be carried out on shaped SIM-1 bodies and films. The parent SIM-1 structured materials are prepared by direct in situ synthesis on a variety of supports for catalysis such as alumina beads and cordierite monoliths, and for separation applications using supports such as alumina tubes, fibers and anodic alumina disks. The hydrophobic SIM-2(C₁₂) prepared on alumina beads is found to be an active catalyst for the Knoevenagel condensation, while its analogous supported membrane on alumina tube is efficient for CO₂/N₂ separation under humid conditions.