Exsolution-prepared LaTi1-xNixOy catalyst for hydrotreating of lignocellulose-derived fast pyrolysis oil and its model vanillin

Abstract

The development of sustainable biofuels as alternatives to petroleum is essential for achieving carbon-neutral transportation, including applications in the aviation and maritime sectors. While paraffins derived from lipids have been applied to sustainable aviation fuel, the commercial-scale production of oxygen-free liquid fuels from lignocellulose remains limited because of the low efficiency of catalytic conversion processes. In this study, a nickel-containing perovskite-based catalyst was synthesized via a combustion method followed by exsolution, targeting the hydrodeoxygenation of lignocellulose-derived fast pyrolysis oil (bio-crude). The exsolved Ni catalyst, derived from LaTiO3-based perovskite precursors, possessed finely dispersed nickel nanoparticles on a macroporous lanthanum–titanium–nickel oxide and exhibited strong metal–support interactions. This catalyst exhibited higher catalytic activity than conventional nickel catalysts supported on lanthanum or titanium oxides. The improved performance was attributed to the high nickel dispersion (18.0–39.3%) and strong metal–support bonding, which enabled the efficient conversion of bio-crude into petroleum-like fuels at 300 °C for 4 h in a batch reactor. Catalytic activity was evaluated using phenolic model compounds, including vanillin, guaiacol, phenol, and syringol, as well as actual bio-crude. These findings suggest that exsolution-derived nickel catalysts supported on mixed oxides are promising candidates for advancing lignocellulose-based sustainable fuel production at a commercial scale.