Iron and chromium MOFs as sustainable catalysts for transfer hydrogenation of carbonyl compounds and biomass conversions

MIL-88B is a class of metal-organic framework (MOF) that has been widely explored in catalysis. Iron- and chromium-based MIL-88B MOFs were prepared and characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and N₂ adsorption/desorption measurements. The MIL-88B MOFs were investigated as catalysts for transfer hydrogenation (TH) of carbonyl compounds (ketones and aldehydes) and biomass derivatives (levulinic acid and furfural) with 2-propanol as a hydrogen donor. Their conversion and selectivity were excellent. The recovered catalyst was reused ten times, with no significant loss in catalytic activity. The recovered catalyst after the tenth run retained its original crystallinity and morphology, which were confirmed by SEM and powder XRD studies. Catalyst reusability for levulinic acid (LA) conversion was also studied. The activation energy for the transformation of LA to γ-valerolactone (GVL) was 25.44 kJ mol^-1. The catalytic performance of MIL-88B(Fe) was compared with that of MIL-53(Fe).