Materials recovery from end-of-life wind turbine magnets

Neodymium-iron-boron permanent magnets are increasingly used in green energy technologies, such as wind turbines and electric vehicles. In the near future, an increasing amount of magnets will reach their end-of-life stage, andtherefore, it is imperative to develop proper recycling routes aimed at the valorization of this waste fraction. In this work, a room temperature hydrometallurgical process was developed aimed at the recovery of both iron and rare earths contained in end-of-life wind turbine magnets. The process is based on a leaching step with nitric acid, followed by two precipitation steps and calcination. Iron hydroxide(III) and rare earth oxide with purity grade equal to 98% and 99%, respectively, were obtained. Based on these results, a process flowsheet was proposed for industrial implementation.