Evaluating ultra-fine friction grinding for the continuous production of nanofibrillated cellulose

Nanofibrillated cellulose (NFC) has diverse applications, but economical large-scale production with minimized ecological footprint remains challenging. A Masuko Supermasscolloider was modified for continuous processing using a pump-controlled circulating system, an in-line viscosimeter, and power consumption meters. Utilizing the upgraded system, we investigated NFC production from Miscanthus biomass under various conditions: different initial cellulose concentrations (1, 1.5, and 2 wt%), process volumes (15 and 25 L) and different grinding times (15–120 min, 15 min intervals). Particle size analysis showed equivalent hydrodynamic diameters of 200–300 nm regardless of processing conditions. Notably, our approach demonstrated 70 % reduction in specific energy consumption by simultaneously increasing process volume from 15 L to 25 L and initial cellulose concentration from 1 wt% to 2 wt%. Additionally, NFC produced at different grinding times was used to prepare carboxymethyl cellulose nanocomposites. Tensile testing demonstrated the same level of mechanical reinforcement regardless of NFC grinding time, highlighting a clear opportunity to reduce the footprint of NFC production while maintaining performance.