Magnetic lignin-derived carbonaceous catalyst for the dehydration of fructose into 5-hydroxymethylfurfural in dimethylsulfoxide

•A magnetic lignin-derived catalyst (MLC-SO3H) was prepared and characterized.•MLC-SO3H possessed a porous structure and a high surface area.•MLC-SO3H was effective for the dehydration of fructose into HMF in DMSO.•MLC-SO3H could be easily separated by using an external magnet.

A magnetic carbonaceous catalyst was prepared by a simple and inexpensive impregnation–carbonization–sulfonation process using the enzymatic hydrolysis lignin residue as a precursor. The resulting catalyst possessed a porous structure with a high surface area and contained Fe3O4 components and SO3H, COOH and phenolic OH groups, and it showed a good catalytic activity for the dehydration of fructose into 5-hydroxymethylfurfural (HMF). By optimizing the reaction conditions, a high HMF yield of 81.1% with 100% fructose conversion was achieved in the presence of dimethylsulfoxide (DMSO) at 130 °C for 40 min. More importantly, the magnetic lignin-derived carbonaceous catalyst could be easily separated from the reaction mixture by using an external magnet, and when it was reused 5 successive runs, no obvious decrease in the yield of HMF was observed, indicating that the magnetic lignin-derived carbonaceous catalyst also exhibited an excellent catalytic stability.

Graphical abstractA magnetic lignin-derived carbonaceous solid acid catalyst was very effective for the dehydration of fructose into HMF in the presence of DMSO.Figure optionsDownload full-size imageDownload as PowerPoint slide