Protonic acid catalysis of sulfonated carbon material: Tunable and selective conversion of fructose in low-boiling point solvent

•The solid acid catalyst was prepared with waste polyurethane elastomer as precursor.•The tetrahydrofuran was reclaimed in preparation process of the catalyst.•The highest HMF yield of 70.1% was obtained in low-boiling solvent.•The 66.0% yield of EMF was observed when the solvent ratio of ethanol/1,4-dioxane equal to 70:30.