Catalytic hydrodeoxygenation of guaiacol as a model compound of woody bio-oil over Fe/AC and Ni/γ-Al₂O₃ catalysts

In this study, Ni/γ-Al₂O₃ and Fe/activated carbon (AC) catalysts were prepared by an incipient impregnation method and then utilized for hydrodeoxygenation (HDO) of guaiacol (GUA). The AC used in the process was derived from bamboo through steam activation. The effects of the calcination temperature, metal loading, and phosphorus addition on the HDO of GUA were systematically investigated. At 300 °C and atmospheric pressure, 91.52% of GUA was successfully transformed into cresol and 1,2-dimethoxybenzene in liquid phase using 10 wt% of the Fe/AC catalyst, which was calcined at 550 °C. Under the same reaction conditions, utilizing 10 wt% of the Ni/γ-Al₂O₃ catalyst, which was calcined at 450 °C, resulted in 96.88% GUA conversion, producing 13.03% of cresol, 58.98% of 1,2-dimethoxybenzene, and 27.99% of 3-methyl guaiacol. Additionally, the reaction pathways of the GUA HDO were proposed based on the obtained product distributions.