Catalytic Conversion of Furans to Aromatics over Ga-MFI Zeotypes with Varying Gallium Content

Journal article, 2025

To address the need for a sustainable chemical industry, commodity chemicals including the aromatics benzene, toluene, and xylenes (BTX) must be produced from renewable feedstocks such as biomass-derived furans. Here, the conversion of 2,5-dimethylfuran (2,5-dmf) into aromatics was studied by step-response experiments in a chemical flow reactor, catalyzed by a series of phase-pure MFI framework Ga-zeotype catalysts with a gallium content ranging from 0.5 to 11 wt %. The lifetime of the catalyst and its aromatic production increase with increasing gallium content, demonstrating a near-40-fold increase in benzene production when increasing the gallium content from 0.5 to 8.6 wt %, while a further increase to 11 wt % leads to a decrease in benzene production due to rapid deactivation of the catalyst by coke. Acid site analysis reveals that aromatization occurs on strong Brønsted acid sites, promoted by strong Lewis acid sites, while isomerization occurs on weak Brønsted acid sites. At high gallium content (≥6.0 wt %), gallium-based nanoparticles are formed, whose presence results in faster catalyst deactivation. The catalysts were active for five consecutive cycles and were readily regenerated, recovering the majority of their initial acid sites.