Synthesis of 5-hydroxymethylfurfural from fructose over chromium-exchanged hydroxyapatite encapsulated γ-Fe2O3

A novel magnetically recoverable chromium-exchanged hydroxyapatite encapsulated γ-Fe2O3 was prepared and its structure was characterized by XRD, FT-IR, and XPS technologies. The prepared catalysts were used to catalyze the conversion of carbohydrates into 5-hydroxymethylfurfual in DMSO. Various reaction parameters such as catalyst loading, and reaction temperature were investigated. A high HMF yield 88.9% was obtained at 120 °C after 240 min. More importantly, the catalyst could be easily separated by the application of an external magnet. The catalyst could be reused for several times without the loss of its significant catalytic activities.