Comparison of Kinetics and Activity of Ni-Based Catalysts for Benzyl Phenyl Ether Catalytic Hydrogenolysis

The influence of the type of support [activated carbon (AC), HZSM-5, and gamma-Al2O3] on the performance of Ni-based catalysts for the catalytic hydrogenolysis (CH) of benzyl phenyl ether (BPE) is investigated. The properties of an Ni-based catalyst are investigated using diverse characterization techniques. An Ni/AC catalyst exhibits the highest dispersion of Ni atoms by CO pulse. The kinetic studies show that the apparent activation energies (E-a) for CH of BPE increase in the order E-a (Ni/AC) E-a (Ni/gamma-Al2O3) E-a (Ni/HZSM-5), and the initial turnover frequencies follow the order of Ni/AC (64 mol mol(Nisurf)(-1) h(-1)) > Ni/gamma-Al2O3 (58 mol mol(Nisurf)(-1) h(-1)) > Ni/HZSM-5 (45 mol mol(Nisurf)(-1) h(-1)). All these results prove that the CH activity of BPE is significantly affected by the type of support, and Ni/AC is the highest activity catalyst in CH of the C-O bond of BPE. Toluene and phenol are major products in CH of BPE at a relatively low hydrogen pressure and high temperature. Based on catalytic experiments, a reaction mechanism is proposed, which provides the theoretical basis for converting lignite into high-value organic molecules.