Lignocellulosic Biomass to Biofuel Production: Integration of Chemical and Extrusion (Screw Press) Pretreatment

Application of mechanical pretreatment in lignocellulosic biomass using screw press or extruder pretreatment recently gained more interest due to high shear, rapid mixing, short residence time, no inhibitor formation (e.g. furfural and HMF), and moderate operating condition. Eventhough, the physical structure of biomass can be modified through this process, the lignin is stay still. This remaining lignin cannot be removed and it subsequently inhibits the enzyme activity to hydrolyze cellulose and hemicellulose. Therefore, the chemical addition to remove lignin is considered as the option to combine with mechanical pretreatment to improve the overall pretreatment efficiency. This review provided the study cases focusing on the feasibility of this process and the selection of suitable chemicals in order to implement this process to practical applications in industries.