Phosphoric acid-activated carbons as catalysts for 5-hydroxymethylfurfural synthesis

Hydroxymethylfurfural (HMF) presents high potential as a biogenic platform chemical derived from renewable resources. This article reports efficient HMF production from fructose using phosphorous-functionalized activated carbon (AC) as catalysts. AC oxidation/phosphorylation was performed using a solution of 20 and 40 wt% of H 3 PO 4 . Catalysts were characterized by XRD, N 2 adsorption–desorption, FTIR, and XPS. After AC functionalization, no significant changes were observed in the morphological and textural properties of the AC. However, the presence of oxygenated groups and phosphate/metaphosphate species provided acid sites that are essential for the dehydration reaction. The effect of reaction conditions, such as time, temperature, and catalyst loading, was investigated, and a kinetic study was also performed. Results showed that 40%H 3 PO 4 /AC was as active as H 3 PO 4 itself. A remarkable HMF yield (90%) was achieved after just 20 min at 180 °C. As the synthesis of HMF remains a challenge on the way to its commercialization, phosphorus-functionalized activated carbons have great potential for the development of more efficient HMF production processes based on a catalyst that is easy to prepare and reuse.