Production of Renewable Jet-Fuel Additives through Hydrodeoxygenation of Isophorone over Ni-Supported, Mesoporous Catalysts

High Resolution Image Download MS PowerPoint Slide This work demonstrates a novel catalytic approach for the synthesis of renewable jet-fuel components by using isophorone as a biomass-derived platform molecule. Isophorone, which can be obtained from biogenic acetone via aldol condensation, can be upgraded to cycloalkanes and aromatics that are suitable for aviation fuel formulations. The upgrading strategy relies on bifunctional catalysts that combine hydrogenation activity from metal sites with dehydration activity from acidic supports. Ni-based catalysts supported on mesoporous materials (Al 2 O 3, TiO 2, ZrO 2, SBA-15, Al-SBA-15, and Al-MCM-41) were synthesized by wet impregnation, thoroughly characterized, and evaluated in a batch autoclave reactor under 35 bar H 2 at 150–250 °C. Support acidity was found to critically govern reaction pathways and product distribution. Strong Brønsted acid sites, particularly in Al-SBA-15 and Al-MCM-41, enhanced hydrocarbon yields but also promoted the formation of heavy species, leading to catalyst deactivation via adsorption and pore blockage. In contrast, Al 2 O 3 -supported catalysts, dominated by medium-strength Lewis acid sites, showed lower initial activity but superior stability, enabling sustained production of hydrodeoxygenated products. These findings highlight the trade-off between activity and stability and underscore the need to balance metal functionality and acid strength in the design of efficient and durable catalysts.