Metal-oxide interaction was widely observed in supported metal catalysts, playing a significant role in tuning the catalytic performance. Here, we reported that the interaction of Ru and MnOx was able to facilitate the hydrodeoxygenation of levulinic acid (LA) to 2-butanol with a high turnover frequency (1.99 × 106 h-1), turnover number (4411), and yield (98.8%). Moreover, this catalyst was capable of removing the hydroxymethyl group of lactones and diol with high yields of products. The high activity of the Ru-MnOx catalyst was due to the strong Ru-MnOx interaction, which facilitated reduction of Ru oxide to Ru0 and Mn oxide to Mn2+. The increased fractions of Ru0 and Mn2+ provided metal and Lewis acid sites, respectively, and therefore facilitated LA hydrodeoxygenation. A linear correlation between the hydrodeoxygenation activity of the Ru-MnOx catalyst and [Mn2+]ln([Ru0]) was observed.
Keywords: 2-butanol; Ru−MnOx interaction; hydrodeoxygenation; hydroxymethyl group; levulinic acid.