Enzymatic Hydrolysis, Kinetic Modeling of Hemicellulose Fraction, and Energy Efficiency of Autohydrolysis Pretreatment Using Agave Bagasse

Agave bagasse is a promising and interesting raw material for the development of second-generation biorefineries. However, the intrinsic resistance (recalcitrance) of lignocellulose biomass to enzymatic hydrolysis is a barrier to its effective conversion into fermentable sugars. Therefore, an autohydrolysis process under subcritical conditions is an alternative to provide the fractionation of biomass in terms of biorefinery concept. In this work, agave bagasse as a feedstock was subjected to the autohydrolysis pretreatment at controlled operational conditions (180°C — 50 min), providing fractionation of biomass > 41.71 % glucan content in the pretreated solid phase (cellulose+lignin fraction). Also, a kinetic modeling of hemicellulose fraction (liquid phase after the pretreatment) for the depolymerization has been studied, considering a linear kinetic mechanism. The cellulolytic hydrolysis process improved the glucose concentration by 40.98 g/L at 72 h with a saccharification yield conversion of 82.58%. The energy efficiency (η) during the autohydrolysis pretreatment was determined (1.039 gsugars/MJ). The design and development of this process will allow establishing optimal operating conditions and energy efficiency for the development of biorefineries with an impact on the circular bioeconomy.