Promoted Hydrogenolysis of Furan Aldehydes to 2,5-Dimethylfuran by Defect Engineering on Pd/NiCo2 O4
Xiang Li1, Likang Zhang1, Qiang Deng1
1Key Laboratory of Poyang Lake Environment and Resource Utilization (Nanchang University) of Ministry of Education, School of Resource, Environmental and Chemical Engineering, Nanchang University, No. 999 Xuefu Avenue, Nanchang, 330031, P. R. China.
Abstract:
Catalytic hydrogenolysis of biobased furan aldehydes (i. e., 5-methylfurfural, 5-hydroxymethylfurfural) to 2,5-dimethylfuran has gained extensive interest for biomass-derived fuels and chemicals. Herein, a class of NiCo2 O4 -supported palladium with considerable oxygen defects was synthesized by hydrogen plasma etching and phosphating methods. The oxygen defects not only promoted the hydrogenation of the C=O group but also enhanced the accessibility of coordinatively unsaturated metal cations with Lewis acidity for the hydrogenolysis of the C-OH group. Meanwhile, the additional Brønsted acidity in Pd/NiCo2 O4-x obtained by phosphating could further strengthen the hydrogenolysis ability by the etherification route of C-OH. Finally, Pd/NiCo2 O4-x exhibited the most effective performance with 2,5-dimethylfuran yields of 92.9 and 90.5 % from 5-methylfurfural and 5-hydroxymethylfurfural, respectively. These catalytic mechanisms were confirmed by in-situ infrared spectroscopy and control experiments. Furthermore, the catalyst showed outstanding recycling stability. This work shows powerful synergistic catalysis in the hydrogenolysis reaction by multifunctional active sites.
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