Catalytic Oxidation of 5-Hydroxymethylfurfural into 2,5-Diformylfuran Over Vanadyl and Cupric Immobilized on Amino-Functionalized MCM-41

Mesoporous MCM-41 was amino-functionalized to immobilize cupric (Cu2+) and vanadyl (VO2+) for preparing MCM–NH2–Cu2+ and MCM–NH2–VO2+ co-catalysts. The as-prepared two catalysts had been characterized by XRD, N2 adsorption–desorption, FT-IR, XPS and TEM. The catalytic performance of MCM–NH2–VO2+ in HMF oxidation could be significantly promoted by using MCM–NH2–Cu2+ as the co-catalysts. Several critical reaction parameters had been investigated, and it indicated that the highest conversion of 5-hydroxymethylfurfural (HMF) obtained was 98.1% at 110 °C in toluene with an optimal 2,5-diformylfuran (DFF) yield of 61.2%. Particularly, the MCM–NH2–Cu2+ and MCM–NH2–VO2+ catalyst exhibited great stability and can be reused and showed no significant loss of their catalytic activities.