A recyclable and regenerable solid acid for efficient hydrolysis of cellulose to glucose

Effective hydrolysis of cellulose to glucose is a crucial step to utilize lignocellulosic biomass for fuels and chemicals. In this study, we adopted the simple Blanc chloromethylation of commercially available Amberlyst-15 to fabricate enzyme-mimic solid acid (A-15-Cl) for cellulose hydrolysis. The results indicated that the chlorine group in A-15-Cl adsorbed cellulose and particularly oligosaccharides through hydrogen bonding while the sulfonic acid group cleaved the β-1,4 glycosidic bonds in cellulose and oligosaccharides. Due to the synergistic effect between the chlorine (adsorbing cellulose) and sulfonic acid (hydrolyzing cellulose) groups, A-15-Cl effectively hydrolyzed cellulose in water achieving a 67.2% glucose yield at 170 °C in 2 h. Moreover, A-15-Cl can be readily separated from the reaction medium by an 80-mesh screen for reuse at least five times without significant loss of catalytic activity .