Processamento hidrotérmico da casca de aveia em modo semi-contínuo

Abstract

Oat husk is a low-cost by product obtained mainly from agro-industrial waste, in this work it was found that this lignocellulose biomass has great potential as a source of renewable, clean and sustainable energy. Subcritical water was used for carbohydrates hydrolysis such as cellulose and hemicelluloses in oat hulls. Therefore, the objective of this study was to obtain fermentable sugars, platform chemicals bio-oil and hydrochar from this biomass by hydrothermal processing. Temperatures of 300 and 330 °C, and solvent/feed ratios of 37.5 and 60.9 g water/g hulls were evaluated on products yield, kinetic profiles and characteristics of bio-oil and hydrochar. The pressure was set at 20 MPa and the reaction time was evaluated up to 30 min. A synergistic conversion of lignocellulose biomass promotes the highest fermentable sugars (4.98 ± 0.48 g / 100 g oat hulls) and platform chemical (5.48 ± 0.06a g / 100 g oat hulls) yields at 300 °C in both solvent/feed ratio (S/F-37.5 and S/F-60.0). The best bio-oil (43.11 ± 5.08 g/100g oat hulls) yield was obtained at 330 °C, also for both solvent/feed ratio. For hydrochar, the evaluated experimental conditions did not affect differences in yield, which was (11.24 ± 2.49 g/100g oat hulls). The hydrochar showed an increase of 1.78 times in HHV (29.70 ± 2.01 MJ/kg), when compared to the value obtained for oat hulls (16.67 ± 0.77 MJ/kg).