In-Situ Hydrodeoxygenation of Methyl Palmitate on a TiO2–ZrO2 Supported Ni3Sn2 Intermetallic Compound with Methanol as a Hydrogen Donor in the Aqueous Phase

Ni3Sn2/TiO2, Ni3Sn2/TiO2–ZrO2(x:y) (x:y indicates the Ti/Zr atomic ratio), and Ni3Sn2/ZrO2 catalysts were prepared by the sol–gel method and tested for in situ hydrodeoxygenation of methyl palmitate with methanol as the hydrogen donor. The Ni3Sn2 intermetallic compound (IMC) is formed in all of the catalysts. The Ti–O–Zr bonds are generated in the TiO2–ZrO2 mixed oxide, leading to more Lewis acid sites on Ni3Sn2/TiO2–ZrO2(x:y) than those on Ni3Sn2/TiO2 and Ni3Sn2/ZrO2, and Lewis acid sites may contribute to the C–O bond cleavage. Especially, among the as-prepared catalysts, Ni3Sn2/TiO2–ZrO2(2:1) has the largest specific surface area and the smallest Ni3Sn2 particles, subsequently giving rise to the highest activity for in situ hydrodeoxygenation. The decarbonylation pathway dominates on all of the supported Ni3Sn2 IMC catalysts. At 330 °C, the yield of n-pentadecane on Ni3Sn2/TiO2–ZrO2(2:1) reaches 91.2%. Ni3Sn2/TiO2–ZrO2(2:1) shows slight deactivation after reaction for five times, mainly due to carbon deposition and the slight sintering of Ni3Sn2 IMC particles.