(193e) Kinetic Study On the Hydrochloride Acid-Catalyzed Hydrolysis of Cellulose to Levulinic Acid and Formic Acid

Both Levulinic acid (LA) and formic acid (FA) are very promising reactive intermediates for production of JP-8 range compounds from cellulosic biomass at very low cost. In this study, kinetics of the acid catalyzed hydrolysis of microcrystalline cellulose (Avicel PH101) to LA and FA was investigated under the following conditions: 160oC - 240oC, hydrochloric acid concentrations of 0.0515 mol/l - 0.926 mol/l, cellulose concentrations of 0.0343 mol/l - 0.309 mol/l, and residence times of 20 min. - 50 min. We found that increasing hydrochloride acid concentration reduced the time to achieve maximum yields, but that yields of LA and FA did not significantly increase with decreasing cellulose concentration. Results showed that the optimal conditions for both acid yields were 180oC, 0.926 mol/l hydrochloric acid concentration, 0.103 mol/l cellulose concentration, and 20 min residence time. At the low temperature of 160oC, both acid yields were very low, even at the highest hydrochloric acid concentrations in this study, while at the high temperature of 240oC, the substantial amounts of char generated reduced acid yields. The kinetics of cellulose degradation reaction was developed to better understand and optimize yields by considering multiple products, including glucose, LA, FA, and Hydroxymethylfurfural.