Efficient and Clean Method for Nano-Lignocellulose Powder by Particle Collision With Magnetic Acceleration

Nano-lignocellulose exhibits great potential for high-value utilization due to its large specific surface area and excellent dispersibility. However, conventional fabrication methods typically rely on chemical reagents, leading to inevitable environmental concerns. Here, a dry processing method for the fabrication of nano-lignocellulose powder is proposed. A mechanical pulverization device based on electromagnetic acceleration is designed, in which multiple coils are sequentially energized to generate magnetic fields, driving magnetic microparticles into high-speed motion. These high-speed magnetic particles collide with lignocellulose and induce its fragmentation, thus enabling the nanoscale fabrication of lignocellulose. Compared with conventional shear-based mechanical pulverization methods, this electromagnetic approach achieves significantly finer particle sizes. Scanning electron microscopy reveals particle sizes of ≈300-400 nm, while Brunauer-Emmett-Teller analysis indicates a 177.2% increase in specific surface area. The absence of solvents ensures retention of the native chemical components. The magnetic fragmentation does not disrupt the lattice, and the original crystalline structure and thermal stability remain unchanged. Mechanical testing of modified biomass composites demonstrates that tensile strength increases with decreasing lignocellulosic particle size. Incorporation of nano-lignocellulose results in a remarkable 72% enhancement in tensile strength compared to neat polylactic acid.