Copper-manganese oxide for highly selective oxidation of 5-hydroxymethylfurfural to bio-monomer 2, 5-furandicarboxylic acid

Spinel copper–manganese oxide catalysts were prepared via the co-precipitation method to be used for the catalytic selective oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA). Morphological characterization revealed that the primary particles of the as-synthesized catalysts were irregular nanoparticles aggregated with each other. The effects of reaction conditions such as time, temperature, and the dosage of oxidant on the catalytic activity were investigated. The experimental results show that the CuMn 2 O 4 showed superior catalytic performance in HMF selective oxidation reaction. In the presence of acetonitrile and tert-butyl hydroperoxide as oxidant, the catalytic reaction can achieve complete conversion of HMF, and the FDCA selectivity reached to 96.4%. The catalyst exhibited good recyclability and recoverability in a three-run recycling test. Mechanism studies reveal that Mn 3+ has a significant influence on the catalytic oxidation and the synergistic interaction between Mn and Cu can facilitate the mobility of oxygen thus improving the catalytic activity. Graphical abstract