Work

Ni–NbOx Bifunctional catalysts for selective hydrodeoxygenation of m-cresol to toluene

Year: 2025

Type: article

Abstract: The catalytic performances of a series of Ni supported on mesoporous silica (SBA-15) and niobia, as well as Ni-NbOx dispersed on SBA-15 were evaluated for the hydrodeoxygenation (HDO) of m-cresol at 300 °C under atmospheric pressure. Under the reaction conditions, hydrogenation and C-C hydrogenolysis pathways yielding only oxygenated products dominated over the monometallic Ni catalyst. In contrast, the Direct DeOxygenation pathway (DDO) leading to toluene was significantly promoted when Ni was in contact with oxophilic NbOx surface. Tuning the Ni-Nb ratio on silica revealed a remarkable enhancement of the DDO rate constant. Indeed, the kinetic rate constant determined over 5Ni5Nb/SBA was about 11 times higher than that measured on the catalyst containing only the Ni phase. This enhanced performance can be attributed to the formation of well-dispersed Ni–NbOx interfacial sites, where the hydrogenation capability of Ni associate with the oxophilic character of Nb5+/Nb4+ species allowing to a more efficient activation of the C-O bonding and promoting the DDO reaction pathway. These results offer valuable insights for the rational design of selective catalysts for the transformation of lignin-derived bio-oils into aromatic hydrocarbons.

Source: Molecular Catalysis

DOI: 10.1016/j.mcat.2025.115516

Authors: Camila A. Teles, Carmen Ciotonea, Ruben Palacio, Diana Lopez, Sébastien Royer, Frédéric Richard