Rare earth element sources, end-use demand trends, and hydrometallurgical separations

Rare earth elements are increasing in demand due to the movement towards electrification. In particular, there is a growing need for high performance rare earth permanent magnets for motors and generators used to convert electrical energy to mechanical energy, and vice versa. Current trends in rare earth demand are reviewed and discussed as the specific rare earth metal demand can influence the choice of feed material and process selection. Australia has the potential to increase the supply of these metals. Rare earth sources in Australia are briefly reviewed, with some discussion on the Mary Kathleen Uranium Tailings opportunity. Much of the cost of recovering rare earths is in the challenging chemical separations, some examples are provided using equilibrium chemical thermodynamic diagrams to explain the specific leaching and precipitation reactions.