ULTRASOUND-ASSISTED PROCESS FOR THE PRODUCTION OF LIGNIN NANOPARTICLES

Method for manufacturing colloidal dispersions of lignin nanoparticles (LNPs) comprising the steps of dispersing raw lignin in aqueous medium such as water, applying ultrasonication (U/S) treatment, during which the temperature is kept constant at a set value of at least 20°C. The method is environmentally benign as it employs an aqueous medium for dispersing the lignin without organic solvents, acids or bases thus eliminating the use of potentially hazardous chemicals or organic solvents. The resulting LNPs are optionally freeze-dried to obtain LNPs of controlled size in solid-state powder form. Also provided is a method of producing LNPs at a pilot-line scale from raw lignin using a customized ultrasound-assisted pilot line. The present invention can produce LNPs with a particle size of 200 nm or less in solid-state form as measured by Transmission Electron Microscopy and a hydrodynamic diameter of 700 nm or less when dispersed in aqueous medium and measured by Dynamic Light Scattering.