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REM recycling isn’t feasible; plethora of experts agree

Jessica Marshall April 14, 2014

 award-winning science, environmental and health journalist. Her work has appeared in Discovery News, New Scientist, Nature, TheAtlantic.com and Science News for Kids, among other outlets. She has a Ph.D. in chemical engineering and has taught science journalism at the University of Minnesota. She lives in St. Paul, Minn. WH

Recycling rare earth elements isn't as easy as recycling glass or plastic — challenges are at nearly every level.

For one thing, the elements are present in small amounts in things like cell phones. As parts get smaller, so do the amounts of material used. In a touch screen, for example, the elements are distributed throughout the material at the molecular scale.

"It's actually getting much harder to recycle electronics," said Alex King of the Ames Lab in Ames, Iowa, director of the Critical Materials Institute — a U.S. Department of Energy-funded "Innovation Hub" focused on strategies for ensuring the supply of five rare earth metals identified by the government as critical. "We used to have cell phones where you could snap out the battery, which is probably the biggest single target for recycling. With smartphones, those things are built so you can't get the battery out, at least not easily."

Cell phones are typically recycled by smashing, shredding and grinding them into powder. The powder then can be separated into component materials for disposal or recycling. But new cell phones incorporate more elements than ever — some around 65 in total. (For comparison, all of industry uses only about 85 elements.) This makes the powder a more complicated mixture to separate than it was with older phones. "It's easier to separate rare earth elements from rocks than from cell phones," King said.

To separate these materials often means "very aggressive solvents or very high temperature molten metal processing. It's not simple," said Yale University industrial ecologist Thomas Graedel.

Because of the nasty materials or large amounts of energy needed, in some cases recycling could create greater environmental harm than mining for the metals in the first place. "A case by case analysis is needed to decide whether a given product is a good recycling candidate," Graedel said.

One recent study calculated the complete energy and environmental impacts of producing a kilogram of the rare earth metal neodymium for magnets by recycling computer hard drives versus mining the same amount of virgin material. In the case considered, recycling had a human toxicity score more than 80 percent lower than mining and used almost 60 percent less energy. However, Graedel noted, "this example recovers neodymium in the alloy form used in magnets." Applications such as use as a glass colorant would require that it be reduced back to elemental form, which would take more resources.

The researchers, led by Benjamin Sprecher at the Materials Innovation Institute in Delft, Netherlands, also found that shredding hard drives for recycling resulted in a 90 percent loss of neodymium. "The large losses of material incurred while shredding the material puts serious doubts on the usefulness of this type of recycling as a solution for scarcity," the researchers wrote. They propose a method in which hard drives are taken apart by hand as a way to address this issue.

When small amounts of rare earths are part of complex mixtures, separation can be too expensive to justify for these elements alone, leading some to suggest that the even more valuable elements within electronics, such as gold, palladium and iridium, may make recycling economically worthwhile. "It might be that the rare earths will pay for the price of doing the processing and the gold, platinum and palladium will be the cash flow," said Eric Peterson of Idaho National Laboratory, who leads the rare earth reuse and recycling research program for the Critical Materials Institute.

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China's recent compliance with the WTO ruling makes this aff pretty non-inherent.  But if you can find defense against that than maybe you can spin it

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