Light-Irradiated Thermal Energy-Promoted Selective Phenol Hydrogenation on Cellulose-Supported Palladium Catalyst with Green Hydrogen

Abstract

The energy and environmental crises urge us to develop a green and sustainable catalytic strategy to achieve chemical transformation. Thus, light-irradiated thermal energy, green hydrogen generated from water electrolysis, and natural cellulose were combined into a catalytic system for phenol hydrogenation to cyclohexanone in this article. The cellulose containing abundant hydroxyl groups improves the catalytic activity of palladium nanoclusters supported on it and hinder the overhydrogenation of cyclohexanone to cyclohexanol. DFT calculations and control experiments demonstrate that the existence of glucose (the monomer of cellulose) on a Pd surface facilitates the dissociative adsorption of phenol on a catalyst and deactivates the hydrogenation of cyclohexanone to cyclohexanol, which further clarifies the higher catalytic activity and better selectivity of Cel-1Pd. More importantly, the selective hydrogenation of phenol to cyclohexanone can be conducted smoothly in a photothermal reactor under irradiation of a xenon lamp, effectively facilitating the benign conversion between light, thermal, and chemical energies.

Carbon Vacancies in Graphitic Carbon Nitride-Driven High Catalytic Performance of Pd/CN for Phenol-Selective Hydrogenation to Cyclohexanone

“…In the one-step route, the catalyst design and preparation are a key step. Many metallic catalysts such as Ni-, Co-, Pd-, − Pt-, Ru-, , and Rh- based catalysts have been reported for phenol-selective hydrogenation to cyclohexanone, but the selectivity at high conversion is not satisfactory due to the further hydrogenation of cyclohexanone. − Therefore, a highly active and selective catalyst system is extremely desirable. Among the reported catalysts, Pd-based catalysts, such as Pd/C, , Pd/ACN (ACN represents N -doped carbon), Pd/MCN@MS-NH 2 (MCN@MS-NH 2 represents mesoporous carbon nanospheres encapsulated with amine-functionalized mesoporous silica), Pd/TiO 2 , Pd/Al 2 O 3 , Pd/MgO, Pd/SiO 2 , Pd/g-C 3 N 4 , , Pd/MCM-41, Pd/MIL-101, , etc., showed high efficiency in phenol-selective hydrogenation.…”