segunda-feira, 27 de dezembro de 2010

A GUERRA DO DISPRÓSIO


Habitual destaque semanal para a coluna do físico Robert Park:

"DYSPROSIUM WAR: U.S. WILL BREAK CHINA’S RARE-EARTH MONOPOLY.

This is not good news. The 15 lanthanide-series metals, plus scandium and yttrium are not at all rare in the Earth's crust, but they’re widely dispersed and difficult to separate. The magnetic properties of dysprosium in particular make it important to the iphone and to hybrid and electric automobiles. China gained its monopoly of rare-earth metals by cutting prices at the cost of environmental degradation. It's a time-honored path for modernization of an economy, but with its new wealth, China now seeks to improve the environment. That's not easy to do in the rare-earth market; the dust from mining operations is mildly radioactive due to thorium and uranium minerals and the separation process uses enormous amounts of toxic acids. The chief US producer was Molycorp which now plans to reopen to its notorious mine in Mountain Pass, CA, closed in part because of environmental degradation. The company promises to employ a cleaner technology, but mining it is an inherently dirty business."

Robert Park

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