Catalytic upgrading of biomass-derived 5-hydroxymethylfurfural to biofuel 2,5-dimethylfuran over Beta zeolite supported non-noble Co catalyst

Abstract

Selectively converting biomass-derived 5-hydroxymethylfurfural (5-HMF) into biofuel 2,5-dimethylfuran (DMF) via hydrogenolysis route is one of significant transformations in the field of heterogeneous catalysis, which is generally performed over supported noble catalysts and/or under harsh conditions such as high temperature (above 423 K, even achieving 533 K) and H2 pressure (1–4 MPa). Herein, non-noble metal (i.e., Co) supported on siliceous *BEA zeolite with open channel systems (Co/Beta-DA) is innovatively proposed for this hydrogenolysis reaction based on strong metal-support interaction. The micro-environment and particle size of metallic Co species were closely related to calcination temperature during the preparation of Co/Beta-DA. The Co species existed in the form of CoOx on the zeolite surface or stabilized inside the zeolite pores as well as isolated Co sites within zeolite framework after calcination (above 723 K), which were reduced by hydrogen to corresponding metallic Co species. It was confirmed that this prepared sample with 20 wt % content of Co, calcined at 723 K, was an efficient catalyst for HMF hydrogenolysis to DMF under mild conditions (423 K, 1.5 MPa H2, 3.0 h), giving an excellent DMF productivity of 1.108 h–1. Thus, this contribution provides new insights for rationally constructing non-noble-based zeolite catalyst for the transformation of biomass into renewable liquid biofuels under mild conditions.