Tailored Co/SBA-15 catalyst for highly efficient hydrodeoxygenation of 5-hydroxymethylfurfural to 2,5-dimethylfuran

Abstract

The design of highly efficient and cost-effective catalysts for the conversion of biomass-derived 5-hydroxymethylfurfural (5-HMF) into sustainable liquid fuel 2,5-dimethylfuran (DMF) is both important and challenging. In this study, we developed a non-noble Co catalyst supported on SBA-15 (25Co/SBA-15). Our results demonstrate that this catalyst exhibits remarkable efficiency in selectively hydrodeoxygenating 5-HMF to DMF, achieving a DMF yield of 96.3 % with complete conversion of 5-HMF under mild reaction conditions (150 °C, 2.0 MPa H₂ for 2 h). Notably, the productivity rate of DMF reached an exceptional value of 19.1 mmol·gcat⁻¹·h⁻¹, surpassing most previously reported catalysts in literature. Additionally, by utilizing two distinct solvents - N,N-dimethylformamide (N,N-DMF) resulting in a high yield of 2,5-bis(hydroxymethyl)furan (BHMF) and tetrahydrofuran (THF) yielding an even higher yield of DMF - our approach enables facile switching between these two products during hydrogenation over the Co/SBA-15 catalyst. Furthermore, our catalyst demonstrates excellent reusability and can be easily regenerated through calcination in air. The exceptional catalytic performance of the catalyst can be ascribed to the synergistic effect between metallic Co and adjacent Lewis acidic Co²⁺ in CoO dispersed on the surface of SBA-15. A dual-site Langmuir–Hinshelwood–Hougen–Watson (LHHW) model was proposed for the hydrodeoxygenating 5-HMF to DMF.