Production of jet fuel-range bio-hydrocarbons over nickel-based catalysts through hydrothermolysis without external H2: Effect of nanoporous supports

Abstract

Bio-aviation fuel, commonly referred to as bio-jet fuel, represents a critical advancement over recent decades, aligning with sustainable energy goals and efforts to mitigate climate change. Catalytic hydrothermolysis is a promising method for producing bio-jet fuel hydrocarbons from biomass without external H₂. This work examined hydrothermolysis of palm oil to produce jet fuel-range bio-hydrocarbons using nickel (Ni)-based catalysts supported on different nanoporous materials, including a proton-form ultra-stable Y (HUSY) zeolite and Santa Barbara Amorphous-15-based mesostructured siliceous (SBA-15) and aluminosilicate (Al-SBA-15) materials. The key properties of these supports were high specific surface area, high thermal stability, shape-selective properties, and tunable acidic properties, which provided the catalysts with bifunctionality for hydrogenation, deoxygenation, and acid-catalyzed reactions. Dealumination of HUSY through mild acid treatment was evaluated for its impact on structural and acidic properties of resulting support material (HUSY-AW). Under optimal conditions (400 °C, 10 wt% catalyst loading, 3-h reaction, and 1:1 oil/water volume ratio), Ni/HUSY-AW achieved the highest yield of alkanes, up to 61.54 %, and an aromatic content of up to 35.17 %. The results obtained suggest that HUSY zeolite, with enhanced mesoporosity and increased active site availability from the acid treatment in Ni/HUSY-AW, improved reactant access and facilitated catalytic reactions. This study contributes to achieving sustainable development goals (SDG) by advancing renewable energy technologies (SDG 7), mitigating climate change impacts through reduced greenhouse gas emissions (SDG 13), and promoting efficient utilization of resources (SDG 12).