Hydrolysis of sugarcane bagasse in subcritical water

In this work, a subcritical water process was used for the hydrolysis of sugarcane bagasse with the aim of producing fermentable sugars. Hydrolysis kinetics was determined using a semi-batch unit equipped with a 50 mL reactor. Different sample loads (2 and 11 g), flow-rates (11, 22, 33, 44 and 55 mL/min) and temperatures (213, 251 and 290 degrees C) were evaluated, while maintaining constant pressure (20 MPa). The liquefaction degree of the sugarcane bagasse was not affected by water flow rate and increased with temperature; the maximum liquefaction degree was 95% for hydrolysis at 251 degrees C and 33 mL/min. The total reducing sugars recovered increased with flow rate up to 23%. The hydrolysis process was completed faster at higher temperatures, requiring 16 min. Maximum monosaccharides + cellobiose + cellotriose yield was 5.6% at 213 degrees C and 33 mL/min. Approximately 60% of the sugars recovered were in the oligomeric form. (C) 2013 Elsevier B.V. All rights reserved.