Selective hydrogenolysis of 5-hydroxymethylfurfural to 2,5-dimethylfuran over Co3O4 catalyst by controlled reduction

2,5-dimethyfuran (DMF), which is produced from 5-hydroxymethyfurfural (HMF) by hydrodeoxygenation (HDO), is a high quality fuel due to the high heating value, the high octane number and the suitable boiling point. Selective hydrogenation of HMF into liquid fuel DMF has been widely researched. In this paper, Co3O4 catalyst was prepared by co-precipitation and was reduced at different temperatures to form Co-CoOx catalysts. The characterization of catalysts was tested by XRD, TEM, XPS, TPR, BET and NH3-TPD. Co-CoOx possessed a high amount of Co metal and CoOx acidic sites, wherein Co worked as the active hydrogenation sites and CoOx acted as the acid promoter to facilitate the selective HDO of HMF to DMF. The synergistic effect of Co-CoOx is the key for HDO of HMF, obtaining 83.3% of DMF yield at 170 degrees C, 12 h and the reduction temperature of 400 degrees C. This method not only saves the catalyst cost, but also promotes the utilization of biomass energy. (C) 2018 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.