Boosting the Hydrodeoxygenation Activity and Selectivity of Ni/(M)-SBA-15 Catalysts by Chemical Alteration of the Support

The influence of the acid sites in the hydrodeoxygenation of anisole performed over Ni catalysts supported on SBA-15 modified with metal oxides (Ni/M-SBA-15, M = Ti, Zr, Al, or Nb) was demonstrated. Catalysts were characterized by SEM-EDX, nitrogen physisorption, XRD, UV-visible DRS, TPR, TPD of ammonia, IR-Py, O-2 chemisorption, and high-resolution transmission electron microscopy. The mesoporous structure and the hexagonal arrangement of the supports were maintained in the catalysts. Ni catalysts supported on modified M-SBA-15 exhibited a higher metal-support interaction, an increase in the acidity and, as a consequence, improved selectivity to cyclohexane. The deoxygenation reaction rate constants increased as Ni/SBA-15 < Ni/Ti-SBA-15 < Ni/Nb-SBA-15 < Ni/Zr-SBA-15 < Ni/Al-SBA-15, which is attributed to the increase in the amount and strength of acid sites, especially of the Br & oslash;nsted ones, which promotes the cleavage of the C-O bond. It is also important to keep the metal/acid sites together to obtain high activity and selectivity to hydrodeoxygenated products.

Automated summary

The influence of acid sites on the hydrodeoxygenation of anisole over Ni catalysts supported on modified SBA-15 was investigated. The modification of SBA-15 with metal oxides increased the metal-support interaction and acidity of the catalysts, leading to improved selectivity to cyclohexane. The increase in the amount and strength of acid sites, especially Brønsted sites, promoted the cleavage of the C-O bond.