Solid base pretreatment to improve the accessibility of lignocellulosic molecules for biomass recovery

Pretreatment with solid base catalysts addressed the challenge of recalcitrance of the lignocellulosic cell wall and provided insight into an economical and environmentally friendly biorefinery technology. Several solid base catalysts were prepared, to establish a reliable assessment of the factors governing their catalytic behaviors. The activity of solid base catalysts, allowing the more accessible lignocellulosic molecules to be depolymerized by enzymes, were evaluated by investigating the properties of the catalysts, the pretreated feedstock, and the residues, after 72 h of enzymatic hydrolysis. A statistical design (CCD) approach was applied to define the factors for the maximum saccharification and an efficient activity recovery. In the case of hybrid pennisetum, an optimized yield of 92% and a retention of 98% activity after 4 cycles were obtained. One of the mechanisms of the solid base catalysts during recalcitrance removal reactions, considering their structures and chemical compositions, was to enhance the accessibility of the cellulosic molecules.