Integrated C–C coupling/hydrogenation of ketones derived from biomass pyrolysis for aviation fuel over Ni/Mg–Al–O/AC bifunctional catalysts

Aldol condensation of biomass-derives coupled with hydrogenation is a promising route for the production of renewable aviation fuel. In this study, a bifunctional catalyst was prepared to integrate the aldol condensation of cyclopentanone and hydroprocessing for aviation fuel in one pot. Due to its strong mild-basic sites, Mg–Al–O performed the best with the total yield of dimer and trimer of 80.4%. Nickel was screened out to be favorable for hydrogenation. Considering the unsatisfactory porous structure of Ni/Mg–Al–O, the bifunctional catalyst was prepared with activated carbon (AC) as carrier. With Ni loading of 20 wt%, the maximum yield of targeted alkanes reached 81.1% over Ni/Mg–Al–O/AC. The calcination and reduction temperature in the preparation process were both optimized at 550 °C. In the reusability test, the yield of targeted alkanes reduced to 31.6% in the 5th run. To attenuate the hydration effect, n-pentane was introduced as solvent, and the bifunctional Ni/Mg–Al–O/AC performed stably in 5 runs. By the design of bifunctional catalyst based on the theoretical basis to realize the integration of C–C coupling and hydrogenation in one pot, it will promote the development of aviation fuel from biomass in a more sustainable and green way.