Catalytic ethanolysis of microcrystalline cellulose over a sulfonated hydrothermal carbon catalyst

The catalytic ethanolysis of microcrystalline cellulose in supercritical ethanol is examined over a sulfonated hydrothermal carbon catalyst (SHTC). SHTC is amorphous carbon containing -OH, -COOH and -SO3H groups with total acidity of 7.15 mmol/g and -SO3H acidity of 1.72 mmol/g. SHTC shows high catalytic activity towards the ethanolysis of cellulose in supercritical ethanol. Complete conversion of microcrystalline cellulose with high yields of ethyl levulinate and ethyl glucoside is obtained. The reaction temperature, time and catalyst amount have significant effects on the catalytic performances of SHTC. Appropriate reaction time and less catalyst amount are favorable for the production of ethyl glucoside, while prolonged reaction time and appropriate catalyst amount favor the production of ethyl levulinate. The highest yield of ethyl glucoside as 420.9 mg/g cellulose is obtained over 0.1 g SHTC at 245 degrees C for 1 h. The highest yield of ethyl levulinate as 817.6 mg/g cellulose is achieved over 0.3 g SHTC at 245 degrees C for 1 h. SHTC shows good stability in the recycle experiments with slight loss of catalytic activity.