Catalytic hydro-deoxygenation of acetic acid, 4-ethylguaiacol, and furfural from bio-oil over Ni2P/HZSM-5 catalysts

In this paper, catalytic hydro-deoxygenation (HDO) of bio-oil's model molecules (acetic acid, 4-ethylguaiacol, and furfural) using Ni₂P/HZSM-5 catalyst was carried out to better identify the products and make the modeling work of HDO process more reliable. Results showed that low temperatures favored the formation of acetaldehyde and acetone during acetic acid HDO, but disfavored the formation of aromatic hydrocarbons. Acetone was produced via the self-ketonization reaction of acetic acid. In most cases of 4-ethylguaiacol HDO, phenol, cresol, and 2, 4-dimethylphenol were the primary products. For furfural HDO, the major furan and CO products proved that the direct decarbonylation of furfural was the main reaction. Accordingly, the main pathways of acetic acid, 4- ethylguaiacol, and furfural HDO were proposed, which could provide significant guidance for the upgrading of crude bio-oil.