Chemical degradation, yields, and interactions of lignocellulosic compounds of poplar wood during dilute acid pretreatment assessed from a comprehensive data set
Julien du Pasquier, Gabriel Paës, Patrick Perré
Abstract
To optimize and guide future valorization of lignocellulosic biomass (LB) in biorefinery into different platform molecules, this work analyses a broad data set to provide a comprehensive overview of the chemical evolution sequences and interactions between different biomass compounds during pretreatment. For this purpose, a comprehensive dataset with a wide range of dilute acid pretreatment (DAP) conditions (2–60 min, 120–190°C, 0–4%wt H2SO4) and severity (Combined Severity Factor (CSF) 0–4) was used. This dataset gathers the chemical composition of 38 DAP-treated samples for 12 compounds (sugars, inhibitors, and lignin) in the solid residue and the liquid phase. All these data were related to the CSF value, so that kinetics are proposed to describe the evolution and quantify the degradation pathways of the C5 and C6-related compounds. All mathematical equations derived from this analysis are provided to the scientific community as supplementary material. The resulting comprehensive reaction scheme can thus be considered as a relevant guide to define the most appropriate DAP conditions depending on the expected objective of the pretreatment. In the case of enzymatic hydrolysis to release monosaccharides, CSFs from 2.0 to 2.5 reveal to be the most appropriate pretreatment conditions, while to produce furfural, a CSF slightly lower than 3 is more adapted. CSFs above 3 should be avoided since they lead to massive losses of polysaccharides.