Abstract

This work studies the role of steam explosion and autohydrolysis as part of the pretreatment of lignocellulosic biomass. Biomass samples were subjected to steam explosion or autohydrolysis as well as autohydrolysis followed by steam explosion in order to identify the contribution of each of these pretreatment techniques on enzymatic digestibility, xylan extraction and lignin release. Steam explosions were carried out at 160-220◦C without residence time and autohy- drolysis at 180-220◦C with a residence time up to 56 min. Results show that steam explosion alone does not have important effects on biomass digestibility, xylan extraction or lignin release. Above 200◦C, steam explosion increases the digestibility of autohydrolysed biomass at low enzymatic dosage. Digestibility at high dosage was also analysed. No signicant differences between autohydrolysed biomass either before or after steam explosion were observed. A mathematical model is proposed to describe the effect of each pretreatment on digestibility.