Common metals like iron, copper and aluminum are already widely recycled. But only about 1 percent of rare earths in old products are reused or recycled, researchers estimate. The world instead relies on mining for its supply of rare earths, about 70 percent of which comes from China, according to the U.S. Geological Survey.
For the latest study, researchers used modeling to forecast how reusing and recycling rare earths could change that. The scientists found that the United States, the European Union and Japan could eventually accumulate rare-earth stockpiles in their old electronics and other products that far exceed what they would find mining the earth.
Based on their modeling, the researchers predicted that, globally, reuse and recycling could reduce the need to mine neodymium, a rare earth element used in wind turbines, by 60 percent in 2050 compared to a business-as-normal base line. For dysprosium, also used in wind turbines, that figure was 67 percent.
The opportunity is there, but some big challenges remain.
Rare earths are often combined with other metals, so extracting them can be difficult. Some rare-earth recycling methods require hazardous chemicals and lots of energy. Extracting the few grams, or even milligrams, of rare earths that are present in each old product can be a daunting task. And there aren’t many systems in place to collect old electronics and other items.
Scientists, though, are working to advance recycling techniques. Researchers at the Department of Energy’s Critical Materials Innovation Hub at Idaho National Laboratory, for example, are developing ways to use microbes instead of toxic chemicals to pull rare earths from old products. Companies like Apple are developing robots that help to recover critical materials, including rare earths, from old iPhones. Twenty-five U.S. states and the District of Columbia already have recycling laws that mandate the collection of some used electronics, though most rare earths in those electronics aren’t being recycled.
Source: nytimes.com