Remember the periodic table from high-school chemistry? The elements of life—like carbon, hydrogen, and oxygen—are near the top. Then, along the bottom, is a row of elements the teacher never talked about. These are the rare earth elements—17 of them make up <0.02% of the Earth’s crust. They have names like lanthanum, neodymium, europium, and yttrium. And, until recently, they seemed like bit players.
It turns out that the rare earth elements are essential to the electronics we all love—cell phones, laptops, and LED light-bulbs. Every Toyota Prius contains some 10 pounds of lanthanum in its batteries. About 60,000 tons of rare earth minerals were mined worldwide in recent years. Nearly all of them were extracted in China.
Rare earth metals pose a number of problems—political, because the ores containing them are concentrated in only a few places; social, since their recycling often exploits some of the world’s poorest people; and environmental, because recycling rare earth metals may be the best way to avoid shortages and harmful mining techniques to extract new supplies.
The amount of rare earth metals in use is about 4 times larger than the annual new production, indicating a significant potential for recycling. But, in many electronic applications only tiny amounts of rare earth metals are used, making it difficult to recover them. When larger amounts are used in a single product—for instance magnets for wind turbines—recycling is easier.
But, for rare earth elements in general, recycling takes on real importance for environmental sustainability.
Photo, taken on January 12, 2012, courtesy of Toyota via Flickr.