Rare earth elements are a group of 17 chemical elements that are crucial components in many modern technologies, and particularly in the engines of electric vehicles and the generators of wind turbines. REE are critical components in many clean energy technologies because they help to make them more efficient, lightweight and durable.
The 17 REE are scandium, yttrium and the 15 lanthanides (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium). These elements are called ‘rare’ not because they are rare in the traditional sense (ie that there is little available), but because they are typically not found in large concentrations or deposits in the earth’s crust, which means they are rather difficult and expensive to mine and extract.
Light rare earth elements (LREE) and heavy rare earth elements (HREE) are used for making high performance permanent magnets, which are used in high quantities in electric motors and generators. REE are also used as phosphors in energy-saving light bulbs and LEDs. The demand for these REE has increased substantially because of the expansion of renewable electricity and increased e-mobility use. To ensure it is viable, a well-functioning recycling system will need to collect substantial quantities of REE. This will require the clear identification of REE and an ability to separate them out from other materials.