Mechanism unraveling for efficient hydrodeoxygenation of fatty acids/esters over highly stable Ni/<scp>Nb₂O₅</scp>‐<scp>SiO₂</scp> catalyst

Abstract The conventional hydrodeoxygenation process for sustainable aviation fuel production using Al 2 O 3 ‐supported Ni‐Mo sulfide catalyst faces dual challenges: sulfur contamination and catalyst hydrothermal instability. This work develops a hydrothermally stable 5% Ni/Nb 2 O 5 ‐SiO 2 catalyst, where strong metal‐support interaction drives Nb to Ni electron transfer to form oxygen vacancies activating oxygen‐rich groups. The addition of SiO 2 increases the specific surface area of the catalyst, while niobium oxide enhances its water resistance. The catalyst exhibits highly catalytic activity in the hydrodeoxygenation of methyl palmitate with &gt;99% conversion and 96% liquid alkane yield, maintaining activity over a 1000‐h on a fixed‐bed continuous‐flow reactor. Furthermore, the catalyst demonstrated stable and reliable performance over a cumulative period of 500 h, comprising 240 h during the hydrodeoxygenation of palm oil and an additional 260 h of continuous operation with waste cooking oil. This work provides a green, non‐sulfur, and stable approach for the production of renewable fuels.