Preparation of Highly Active Cu/SiO2 Catalysts for Furfural to 2-Methylfuran by Ammonia Evaporation Method

Biomass plays an important role in the green manufacture of high value-added chemicals. Among them, the conversion of furfural (FFA) into 2-methylfuran (2-MF), catalyzed by a copper-chromium catalyst, is important in its industrial application. However, the use of chromium is limited due to its toxicity and pollution of the environment. In this paper, a Cu/SiO2 catalyst, prepared by the ammonia evaporation method, shows a better catalytic performance compared with that prepared by the co-precipitation method for the vapor-phase hydrodeoxygenation of FFA. The selectivity of 2-MF is higher than 80% with almost a complete conversion of FFA. Combined with the characterizations, the superiority of the ammonia evaporation method is attributed to the reduction of highly dispersed copper species and the increased Cu+/(Cu+ + Cu-0) ratio due to the formation of a large content of copper phyllosilicate during the preparation. Moreover, Cu+ sites can act as a weak acid site, which improve the surface acidity of the catalyst and facilitate the formation of 2-MF. This new catalytic system provides a feasible and promising strategy for the industrial preparation of 2-MF from FFA, and effectively utilizes biomass resources to promote the development of biomass industry.