A mild oxidation strategy for oxidation-hydrolysis of cellulose without additional catalyst

O-3 was applied as an efficient oxidant in the pre-oxidation of cellulose under the mild conditions for oxidation-hydrolysis of cellulose without additional catalyst. After treated by O-3 at 120 degrees C for 4 h, some hydroxymethyl groups on cellulose structure were oxidized to carboxyl groups which act as the active sites for the hydrolysis under the hydrothermal conditions to break the glycoside bonds of cellulose. Much lower oxidation temperature and short treatment time make this method more competitive than the conventional oxidation-hydrolysis strategy (210 degrees C, 48 h) where O-2 was used as the oxidant. Furthermore, in this oxidation-hydrolysis strategy, efficient hydrolysis of cellulose to glucose can be realized with a high cellulose/water mass ratio (40 wt%). Correspondingly, a glucose aqueous solution with high concentration (50.9 g L-1) can be obtained. High concentration of glucose is favorable for the further application in fermentation or chemical conversion. This work provides a new, mild, and green oxidation strategy for oxidation-hydrolysis of cellulose without additional catalyst.