Organosolv lignin hydrophobic nanoparticles as low-carbonfootprint biodegradable flotation collectors (LIGNOFLOT)

Purpose and goal
1. Establish a novel sustainable flotation process for the extraction of base metals from sulfide ores based on the replacement of toxic xanthate derivatives with biodegradable non-toxic lignin nanoparticles 2. Develop a process with low environmental impact (production of lignin nanoparticles take place in mild conditions and are non-toxic) using eco-friendly forest biomass organosolv fractionation technology

Expected results
Biodegradable organosolv lignin nanoparticles to be used as efficient flotation collectors of base metals from sulphide ores and replace the toxic xanthate derivatives

Structure and implementation
Forest materials will be subjected to organosolv pretreatment for the isolation of organosolv lignin. Then the organosolv lignin will be dissolved in ethanol/water solution followed by processing using a pressure homogenizer to produce organosolv lignin nanoparticles. Functionalization of of organosolv lignin to increase its hydrophobicity will be performed via esterification of hydroxyl groups. Non-functionalised and functionalised lignin nanoparticles will be evaluated as flotation collectors during the flotation of pure metals.