Synergistic contribution of metal-acid sites in selective hydrodeoxygenation of biomass derivatives over Cu/CoO catalysts.

The efficient hydrodeoxygenation (HDO) of biomass derivatives to yield specific products is a significant yet challenging task. In the present study, a Cu/CoO catalyst was synthesized using a facile co-precipitation method, and subsequently used for the HDO of biomass derivatives. Under optimal reaction conditions, the conversion of 5-hydroxymethylfurfural reached 100% with a selectivity of ∼99% to 2,5-diformylfuran. In combination with the experimental results, systematic characterizations revealed that CoO, as the acid site, tended to adsorb CO bonds, and the metal sites of Cu were inclined to adsorb CO bonds and enhance CO bond hydrogenation. Meanwhile, Cu was the main active site for 2-propanol dehydrogenation. The excellent catalytic performance could be attributed to the synergistic effects of Cu and CoO. Further, by optimizing the ratio of Cu to CoO, the Cu/CoO catalysts exhibited notable performance in HDO of acetophenone, levulinic acid, and furfural, which verified the universality of the catalysts in the HDO of biomass derivatives.