Physical and chemical pretreatment of sugarcane bagasse for enhanced acid hydrolysis

Abstract

The second-generation ethanol production process proceeds in several stages. One of them is the pretreatment of lignocellulosic materials, which consists in the disruption of vegetal fibers, promoting partial removal of lignin and hemicelluloses. Pretreatment methods are of great importance to the effectiveness of the hydrolysis stage due to the increase in accessibility of hydrolysis reagents to the interior of the fibers, improving the conversion of lignocellulosic materials. In this study, a pretreatment of sugarcane bagasse was performed, involving milling and ultrasound treatment in alkaline or acidic medium. After the pretreatments, the materials were submitted to acid hydrolysis reactions. To evaluate the efficiency of the pretreatments, the amount of total reducing sugars (% TRS) of the hydrolysis products were assessed. The best results were obtained for the alkaline pretreatment of sugarcane bagasse, with almost 20% of TRS.