Aerobic oxidation of 5-hydroxymethylfurfural into furan compounds over Mo-hydroxyapatite-encapsulated magnetic γ-Fe2O3

In this study, magnetic γ-Fe 2 O 3 @ HAP-Mo catalyst was successfully prepared and characterized. The activity of the as prepared γ-Fe 2 O 3 @ HAP-Mo catalyst was evaluated by the oxidation of 5-hydroxymethylfurfural (HMF) with molecular oxygen. Some important reaction parameters were investigated and it was found that both the solvent and the reaction temperature showed great effect on HMF conversion and products selectivity. The highest HMF conversion of 95.8% was obtained in 4-chlorotoluene at the reaction temperature of 120 °C for 12 h, and the corresponding 2,5-diformylfuran, 2,5-furandicarboxylic acid and 5-hydroxymethyl-2-furancarboxylic acid yields were 67.5, 19.6 and 8.7%, respectively. The γ-Fe 2 O 3 @ HAP-Mo catalyst could be easily separated from the reaction mixture and reused several times without the loss of its catalytic activity.