Soft modelling of spruce conversion into bio-oil through pyrolysis – Note I: steam explosion and LPMO-activated enzymatic saccharification

Biorefinery converts biomass into energy and high-value bioproducts, such as bio-oil. The combined power and fuel generation is particularly attractive for energy transition and reduction of non-biogenic CO2 emissions. Biomass conversion requires a series of complex treatments. The development of reliable models is essential for scaling up and designing. Soft-modelling approach provides a simplified description of the system without losing accuracy. This contribution presents a soft model for steam explosion (after impregnation with carbocation scavengers) and enzymatic saccharification (boosted with H2O2-driven oxidative depolymerization by LPMO enzymes). These are two key pre-treatments for the extraction of carbohydrate fraction prior to pyrolysis of lignin-rich solids to produce the bio-oil. The proposed saccharification model accurately predicts experimental data in the range of interest for steam explosion temperature and enzyme concentrations investigated. This approach can be considered general and is potentially applicable to every kind of biomass.