Exploring the Reaction Mechanisms of Furfural Hydrodeoxygenation on a CuNiCu(111) Bimetallic Catalyst Surface from Computation.

Abstract

In this study, the selectively catalytic hydrodeoxygenation of furfural (F–CHO) to 2-methylfuran (F–CH3) on the CuNiCu(111) bimetallic catalyst surface was systematically investigated based on the periodic density functional theory, including dispersion correction. The formation of furfuryl alcohol (F–CH2OH) involved two steps: the preferred first step was the hydrogenation of the branched C atom, forming the alkoxyl intermediate (F–CHO + H = F–CH2O), and the second step was H addition to the alkoxyl group, resulting in furfuryl alcohol (F–CH2O + H = F–CH2OH), which was the rate-controlling step. In contrast, in the formation of 2-methylfuran, the first step was the dehydroxylation of furfuryl alcohol, resulting in alkyl (F–CH2) and OH (F–CH2OH = F–CH2 + OH) groups, the second step was the hydrogenation of F–CH2 (F–CH2 + OH + H = F–CH3 + OH), and the rate-controlling step was the hydrogenation of OH to H2O (OH + H = H2O). Based on the comparison results of the NiCuCu(111), Cu(111), and CuNiCu(111) surfaces, it was concluded that the catalytic performance of the catalyst was closely related to the adsorption structure of furfural. These results provide a basis for studying the intrinsic activity of NiCu catalysts during the hydrodeoxygenation of refined oxygenated compounds involving biomass-derived oils.