What are rare earths?
What are rare earths?
Rare earths, also known as rare earth elements, refer to 17 elements on the periodic table that include the lanthanide series from atomic numbers 57, lanthanum (La) to 71, lutetium (Lu), plus scandium (Sc) and yttrium (Y).
From the name, one may assume that these are “rare,” but in terms of minable years (the ratio of confirmed reserves to annual production) and their density within the earth’s crust, they are actually more abundant than led or zinc.
By effectively using rare earths, one can expect dramatic changes to conventional technology; changes such as technological innovation through newfound functionality, improvements to durability in structural materials and improved energy efficiency for electronic machines and equipment.
What are they used in?
The first industrial usage of rare earths was for the flint in lighters. At that time, the technology for separation and refinement had not been developed, so a mixture of multiple rare earth and salt elements or unaltered misch metal (alloy) was used.
From the 1960’s, separation and refinement became possible and the properties contained within each rare earth were made evident. For their industrialization, they were first applied as cathode-ray tube phosphors for colored TVs and on high refractive camera lenses. They have gone on to contribute to reducing the size and weight of computers, digital cameras, audio devices and more through their use in high performance permanent magnets and rechargeable batteries.
In recent years, they have been gaining attention as a raw material for hydrogen-absorbing alloys and magnetostriction alloys.
Contributing to the environment and energy conservation through rare earths
One of the reasons that rare earths have been gathering attention as “a resource supporting the future” is due to their contributions to the environment and energy conservation.
Hybrid cars came into being only after the existence of “highly efficient permanent magnet motors” and “safe and clean nickel-metal hydride batteries”; both of which are made from rare earths.
Rare earths are also used in automotive exhaust cleaning catalysts and honeycomb catalysts to allow for the more efficient application of the world’s energy. From here on, they will be an even more essential resource when it comes to developing safe and recyclable devices.