Catalytic aerobic oxidation of 5-hydroxymethylfurfural over VO2+ and Cu2+ immobilized on amino functionalized SBA-15

Abstract

Amino modified SBA-15 (SBA-NH2) was used to immobilize vanadyl (VO2+) and cupric (Cu2+) ions, giving SBA-NH2-VO2+ and SBA-NH2-Cu2+ catalysts, respectively, and the as-prepared catalysts were characterized by XRD, XPS, TEM and Nitrogen adsorption–desorption technologies. The catalytic performance of the SBA-NH2-VO2+ catalysts for the oxidation of HMF can be enhanced by the use of SBA-NH2-Cu2+ as the co-catalyst. Several important reaction parameters were investigated, and it was found that the reaction solvent showed a great effect on the oxidation of HMF. The highest HMF conversion and product selectivity were obtained in aromatic solvents. The highest HMF conversion reached 98.8% at 110°C in 4-chlorotoluene, affording DFF and 2,5-furandicarboxylic acid (FDCA) with yields of 28.9% and 62.7%, respectively. More importantly, the catalysts could be recycled and showed no significant decrease of their catalytic activities.