Selective Preparation of 4-Alkylphenol from Lignin-Derived Phenols and Raw Biomass over Magnetic Co–Fe@N-Doped Carbon Catalysts

Graphical Linked in to lignin : 4-Alkylphenol is produced selectively over a magnetic Co 1 –Fe 0.1 @NC catalyst from real lignin oil as feedstock, which is obtained by a “lignin-first” strategy from raw biomass. The incorporation of Fe attenuates the adsorption of 4-alkylphenol to the catalyst, which inhibits the further hydrogenation of 4-alkylphenol to 4-alkylcyclohexanol. Lignin valorization to produce high-value chemicals selectively is an enormous challenge in biorefinery. In this study, 4-alkylphenol, formed by breaking the robust C aryl −OCH 3 bonds solely with the retention of other structures in lignin-derived methoxylalkylphenols, was produced selectively over a Co 1 –Fe 0.1 @NC catalyst from real lignin oil as feedstock, which was obtained by a “lignin-first” strategy from either birch or cornstalk. A yield of 64.7 or 88.3 mol % of 4-propylphenol was obtained if birch lignin oil or eugenol was used as the substrate, respectively. The catalysts were characterized by using methods that include Brunauer–Emmett–Teller measurements, XRD, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, and temperature-programmed desorption with synchrotron vacuum ultraviolet photoionization mass spectrometry. The results of catalyst characterization and comparison experiments indicated that CoN x was the main active phase for demethoxylation and hydrogenation, and the incorporation of Fe weakens the adsorption of 4-propylphenol to the catalyst, which inhibits the excessive hydrogenation of 4-propylphenol. This work shows the potential to produce high-value-added 4-alkylphenol from renewable raw biomass.