关键词: 生物质, 芳香含氧化合物, C— O键, 加氢脱氧, 催化机理

Abstract:

Lignocellulosic biomasses contain aromatic ring structures but have high oxygen contents. The key issue for the high value utilization of biomass-derived aromatic oxygenates is the activation and breaking of C— O bonds. There are various types of C— O bonds in biomass-derived aromatic oxygenated compounds, mainly including C_aryl—O(H) bonds connecting the carbon of the aromatic ring with the hydroxy-oxygen, ether bonds C_aryl—O—CH₃, and C\stackrel{}{̿}O bonds in the side chain of the aromatic ring. Catalytic hydrodeoxygenation (HDO) is an effective way for cleavage of C—O bonds of aromatic oxygenated compounds. This paper reviews the current research status of complete C— O bond cleavage and selective C—O bond cleavage of biomass-derived aromatic oxygenates, and describes the catalytic cleavage mechanism of C— O bond for typical aromatic oxygenates such as phenol, methylphenol, anisole, guaiacol, eugenol and vanillin. The roles of catalyst properties and structures such as hydrogenation ability, oxophilicity, acid sites, electronic structure and metal sites on C— O bond cleavage of aromatic oxygenated compounds are analyzed. Furthermore, some key issues and research focuses on the C— O bond breaking of aromatic oxygenated compounds are proposed.

Key words: biomass, aromatic oxygenates, C— O bonds, hydrodeoxygenation, catalytic mechanism