Hydrodeoxygenation of phenol on bifunctional Ni-based catalysts: Effects of Mo promotion and support

Hydrodeoxygenation (HDO) of phenol dissolved in decalin was studied over H-2-activated Ni and Mo-Ni catalysts supported on alumina and amorphous silica alumina (ASA) in the context of the O-removal from bio-liquids. The activity test was carried out in a flow reactor at 310 degrees C and total hydrogen pressure of 3 MPa. The catalyst samples were characterized by several physico-chemical techniques (S-BET, H-2-TPR, HRTEM, DRIFT spectroscopy of adsorbed CO and NH3, Raman spectroscopy, XPS, SEM-EDS and HRTEM) in order to obtain catalyst activity-structure correlation. After 4 h on stream, the Mo-Ni/ASA catalyst displayed the highest activity in the HDO of phenol, which was linked with its highest Ni dispersion, the Mo promoting action and largest acidity. The MoNi/ASA catalyst displayed 2 times higher yield of O-free products than a commercial NiMoP(S)/Al2O3 catalyst activated by sulfidation. The role of metals and metal oxides species in HDO reaction has been discussed.