Study of the performance of SiO2-supported Mo2C and metal-promoted Mo2C catalysts for the hydrodeoxygenation of m-cresol

The performance of Mo2C, Mo2C/SiO2, Ni-MoxCy/SiO2, and Cu-MoxCy/SiO2 catalysts for the hydrodeoxygenation of m-cresol at 300 °C and atmospheric pressure was investigated. Ni/SiO2 and Cu/SiO2 were used as references. To get more insight into the effect of the promoters during the synthesis of the Mo carbides, the carburization of the supported catalysts was followed by X-ray spectroscopy under 20 % (v/v) CH4/H2. The results showed that the presence of a second metal promotes the first step of reduction, and it is related to the crystallinity of the mixed molybdates in the initial promoter species, but that it does not assist the carburizing step. All carbides were highly selective to toluene (> 96 %), indicating that Mo2C species is the active site responsible for the deoxygenation of m-cresol. Mo2C/SiO2 catalyst carburized at 400 °C was inactive, which is due to the lower oxophilicity of the oxycarbide species (MoO2−xCx).