Defibrillated Celluloses via Dual Twin-Screw Extrusion and Microwave Hydrothermal Treatment of Spent Pea Biomass

The defibrillation of lignocellulosic matter from pea waste using a dual approach of twin-screw extrusion and microwave hydrothermal treatment (MHT) in the presence of water alone from 120 to 200 °C is reported. Gradual “scissoring” of biomass macrofibers to microfibrils was observed alluding to the hydrothermal microwave-assisted selective scissoring (Hy-MASS) concept. The morphology and properties of two types of MFC: PEA (nonextruded) and EPEA (extruded) were compared. The EPEA samples gave a higher crystallinity index and thermal stability, reduced lignin and hemicellulose content, narrower fibril width, better water holding capacity slightly, and higher surface area compared with their nonextruded counterparts (PEA). Twin screw extrusion as a pretreatment method followed by MHT represents a potential way to produce microfibrillated cellulose with improved physical performance from complex biomass sources.