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© 2021 American Chemical Society.Selective cleavage of C–O bonds in diphenyl ether (DPE), a lignin–derived 4–O–5 linkage, is a challenging topic and of great significance to produce value–added aromatic products for sustainable future. Activated carbon (AC) with different pore structures has different catalytic effects on the reaction. Herein, Ni catalysts supported on AC–1, AC–2, and AC–3 with specific surface area (SSA) values of 829, 1731, and 2399 m2/g, respectively, were investigated in the hydrogenolysis and hydrolysis of DPE. The proper pore structure of AC facilitates the entry of reactants and promotes the reaction. AC with a larger SSA and stronger hydrophilicity was more conducive to metal dispersion and water adsorption to promote the hydrogenolysis/hydrolysis of DPE. The apparent activation energy (Ea) and the turnover frequency further demonstrated that Ni/AC–3 possessed the highest catalytic activity compared to Ni/AC–2 and Ni/AC–1. Catalytic hydrogenolysis/hydrolysis of DPE can be therefore achieved over Ni/AC–3 under mild conditions (180 °C and 1 MPa H2), which is highly selective to afford cyclohexane and cyclohexanol as the major products with the selectivities of 35.5 and 63.9%, respectively. The application of a hydrophilic Ni/AC catalyst with a high SSA may provide a promising approach for the valorization of lignin–derived fragments.
