The rare earth metals are actually not always that rare! Some of the rare earth metals are among the most abundant in the earth’s crust. They are often incredibly difficult to extract, however.
There are fifteen rare earth metals that reside on the periodic table of the elements as the lanthanoids. Scandium and Yttrium are also rare earth metals.
Rare earth metals have special properties, such as catalytic, chemical, electrical, metallurgical, nuclear, magnetic or optical, making rare earth metals valuable for application in an ever increasing host of advanced technological functions.
But, as mentioned earlier, these substances can often be difficult to extract, as they can reside in ores, and require complicated and multi stage processes in order to extract them in usable form.
The primary use of lanthanoids for the hybrid car industry are in the permanent magnets used in the hybrid car batteries. The Toyota company Prius is the most prevalent consumer of lanthanoids, with a major production goal. The Prius uses up to 2.2 pounds of lanthanoid in its batteries, with more needed to increase the future capacities of the battery.
Lanthanoids are contained in “mischmetal” or natural alloys that have varying quantities of the lanthanoids.
The bad news is that the Chinese have bought up most of the world’s stock of mischmetals and lanthanoids, and competition for these substances is high.
The four “rare earth metals”, or lanthanoids, used in the hybrid car industry are Lanthanum, neodymium and dysprosium and terbium.
Lanthanum is made from the minerals monazite and bastnasite. It is a soft, malleable, easily oxidizing metal The Toyota Prius uses 22-33 pounds, or 10-25 kg of lanthanum.
Neodymium is the major component of hybrid car batteries. It is a metal, silver in color which oxidizes. It is also extracted from the minerals monazite and bastnasite, and is not found by itself or in natural form as a metal. Neodymium has the most powerful magnetic potential of the lanthanoids. 2.2 lb, or 1 kilogram of neodymium is used in the Toyota Prius, with increases on the way.
Dysprosium is a metallic silver lanthanoid that is found in several minerals, including xenotime, monazite and bastinite and several others. But dysprosioum rarely shows up as a free element on its own. Dysprosium is used along with terbium to stabilize the magnetic properties of the neodymium.
Terbium is also used in hybrid car batteries to help the neodymium to maintain its magnetic properties. It is a white-silver metal that is more stable in air than other lanthanides. Terbium is one of the most reactive to magnetic fields and helps, along with dysprosium to stabilize the molecular structure of the neodymium magnet and to keep the atoms in line.
“Rare earths are vital, and China owns them all”
The Wall Street Journal Digital Network, Market Watch, 24 Sep 2009.
http://www.marketwatch.com/story/rare-earths-are-vital-and-china-owns-them-all-2009-09-24
Wikipedia Lanthanum
http://en.wikipedia.org/wiki/Lanthanum
Wikipedia neodymium
http://en.wikipedia.org/wiki/Neodymium
Wikipedia Dysprosium
http://en.wikipedia.org/wiki/Dysprosium
Wikipedia Terbium
http://en.wikipedia.org/wiki/Terbium
As hybrid cars gobble rare metals, shortage looms
http://www.reuters.com/article/idUSTRE57U02B20090831
Backpedaling, China Eases Proposal to Ban Exports of Some Vital Minerals
http://www.nytimes.com/2009/09/04/business/global/04minerals.html
