Integrated study on the role of solvent, catalyst and reactant in the hydrodeoxygenation of eugenol over nickel-based catalysts

Abstract

The hydrodeoxygenation (HDO) of phenols to hydrocarbons is a very promising technique process for the lignin valorization. To reveal the role of reactant, solvent and catalyst, the HDO experiments of eugenol to hydrocarbons were carried out at 523K under 3MPa H2 over Ni catalysts supported on activated carbon (AC) and MFI-type zeolites in polar water and nonpolar n-hexane, respectively. It was found that Ni/AC was more efficient for the HDO of eugenol in water than in n-hexane, but Ni/HZSM-5 was just the opposite. The respective roles of Brønsted acid sites and Lewis acid sites on supports were also investigated by employing NaZSM-5, HZSM-5 and silicalite-1 as supports. It was revealed that Brønsted acid showed superior advantages (TOF: 37.9h−1 to 11.1h−1) over Lewis acid in the dehydration of 4-propyl-cyclohexanol. Oxygen-containing functional groups could be removed from the aromatic ring completely over Ni/HZSM-5 in n-hexane.