There are few products more in need of a revival of U.S. manufacturing than rare earth metals. Once an important producer, the U.S. ceded its position to China when prices fell sharply a number of years ago. But with prices now at record highs, America needs to again become a major producer, given the substantial amounts of some of these somewhat esoteric metals required for the production of wind turbines(neodymium, dysprosium), hybrid car batteries(lanthanum), lasers(dysprosium), nuclear reactor control rods(dysprosium), TV displays(europium, yttrium), etc. Molycorp is reopening a mine at Mountain Pass, Calif. (Chemical Week, April 11/18, 2011, Ppg. 19-23) and other, smaller producers are also gearing up. A huge potential source of rare earth metals exists in Alaska, but it will be years before mining there could even start., let alone processing and separation. In the meantime, China will have a 90%+ monopoly on rare earths supply, an unacceptable situation for America and Europe, where firms want to installa lot more wind turbines. These each use a large amount of neodymium for high efficiency magnets.
Mined materials usually consist of a mixture of a number of metal oxides, which need to be separated and refined, a difficult task given also the fact that some of the ores contain radioactive oxides (thorium and uranium). The chemistry of separating the rare earths is complex because their chemical behavior is quite similar. Unit operations employed include fractional crystallization, fractional precipitation, ion-exchange, solvent extraction and separation based on selective oxidation-reduction. The challenge is to develop large-scale separation techniques, requiring a number of chemical engineering disciplines. Given the complexity of separation techniques, it seems unlikely that current producers in China and prospectively in Malaysia will share their knowhow and license this technology. So, here is an opportunity for U.S. firms to develop proprietary U.S. manufacturing techniques to produce several key rare earths in large quantities.
China has about 6000 researchers and chemists working in the rare earths sector. In contrast, only one U.S. school, the Colorado Schol of Mines, offers a course in rare earths chemistry. Some chemical firms, in addition to Molycorp, do have some knowhow in the area. Rhodia, now owned by Solvay, supplies a number of rare earth compounds, but it appears that its main production center is in China. Grace Davison worked on separating rare earths from spent catalyst some years ago.
Clearly, we are in a cacth-up situation, but the U.S. has faced this kind of challenge before. The domestic resource is available. Large-scale oxide separation plants need to be built as efficient separation techniques are developed and piloted. Chemical engineers: here is a golden opportunity!