Highly stable Mo-based catalysts for selective hydrodeoxygenation to produce diesel-like hydrocarbons

Abstract

Unsaturated hydrocarbons with C=C bonds prepared from bio-oils are excellent substitutes for petrochemical oils, which are characterized by high stability and high calorific value. Currently, the most effective way to prepare such compounds is hydrodeoxygenation of unsaturated oils and fats, and an ideal approach would be selective hydrodeoxygenation. Mo/C-based catalysts exhibit excellent performance in this type of reaction; however, their low oxidation resistance limits their stability, and hence their applicability. Herein, we report a novel Mo-based catalyst with high stability by exploiting the variable valences of transition metal dopants. A Cu-Mo/C catalyst proved to be most effective for the hydrogenation of methyl oleate to produce diesel-like hydrocarbons, showing excellent activity and stability. XRD, XPS, and EPR characterizations have indicated that the presence of oxygen vacancies is conducive to the preferential adsorption of carbon–oxygen bonds and avoids the hydrogenation of C=C bonds. Subsequently, the active species of the Mo-based catalyst promotes the cleavage of the carbon–oxygen bonds.