Novel copper pyrovanadate (Cu 2 V 2 O 7 )-Al 2 O 3 spherical beads were prepared by alginate-assisted sol-gel method using ammonium vanadate, copper nitrate, and pseudo boehmite as precursors, characterized by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission electron microscope (TEM), X-ray Photoelectron Spectroscopy (XPS), BrunnerÀEmmetÀTeller (BET), X-Ray Fluorescence (XRF) and nitrogen adsorption-desorption technologies and used as catalysts for the selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF). The effects of calcination temperature on catalyst structure, morphology, and catalytic activity were investigated. The results showed that the formation of Cu 2 V 2 O 7 crystalline phase at a high temperature can improve the catalyst activity significantly. Under the optimal reaction conditions, Cu 2 V 2 O 7 -Al 2 O 3 -700 exhibited an HMF conversion of 99.9% and DFF selectivity of 99.8%, respectively. After a five-run recycling test, the activity of the catalyst can remain about 80%.
Highlights• Cu 2 V 2 O 7 was used as catalysts for aerobic oxidation of HMF into DFF.• Alginate-assisted sol-gel method improved interaction between Al 2 O 3 and Cu 2 V 2 O 7 .• Cu 2 V 2 O 7 -Al 2 O 3 beads with 1.8-mm diameter showed good industrial application potential.