Selective hydrodeoxygenation of aromatics to phenols by Pt nanoparticles supported on La-modified Al2O3

Abstract

Phenols are pivotal chemicals produced mainly from fossil raw materials. The selective hydrodeoxygenation of lignin derivatives shows great potential in the production of phenolic chemicals, but achieving high yield remains a challenge. Herein, we report a catalyst of Pt nanoparticles (NPs) supported on La-modified alumina (Pt/La–Al₂O₃), which can highly selectively fracture the ether C–O(R) bond in guaiacol without hydrogenation of the benzene ring, with a phenol selectivity of over 90.7% and also demonstrates broad applicability to various other substrates with different substituents. The reaction mechanism was investigated by control experiments and in situ diffuse reflection infrared Fourier transform (DRIFT). The synergistic interactions between Pt nanoparticles and La atoms enable the demethylation of aromatic compounds without hydrogenation of the benzene ring, and thus, desired phenols were generated. This work offers new insights for the design and construction of high-efficiency hydrodeoxygenation catalysts to achieve the synthesis of phenols.