May/June 2013
Global supply worries and price volatility have motivated a variety of stakeholders to explore whether recycling rare earth metals is possible—or profitable.
By Theodore Fischer
Despite their name, you can find rare earth metals just about everywhere. They’re in smartphones, earbuds, computer hard drives, microphones, and other common electronics as well as wind turbines and hybrid cars. They’re part of LEDs, LCDs, and energy-efficient fluorescent lighting, not to mention camera lenses, cigarette-lighter flints, battery electrodes, and catalytic converters. One rare earth metal even works as an emissions-reducing additive in diesel fuels.
Rare earths became rarer in 2011, when China—the world’s largest producer of rare earth minerals—cut its exports of the materials, sending prices through the roof. This wake-up call inspired manufacturers, governments, mining companies, and others with an interest in rare earth elements to seek additional supplies through mining and, notably, recycling. Though rare earth prices have moderated from their recent peaks, supplies remain unstable and unpredictable, making a strong case for the stepped-up recycling of the metals.
A Rare Earth Primer
The names of the 17 rare earth elements sound like they come from a science-fiction novel: cerium, dysprosium, erbium, europium, gadolinium, holmium, lanthanum, lutetium, neodymium, praseodymium, promethium, samarium, scandium, terbium, thulium, ytterbium, and yttrium. Of these elements, 15 are considered lanthanides, with the other two—scandium and yttrium—included in that group because their chemical makeup is similar to the others and because they often appear in the bastnäsite, monazite, and loparite deposits that contain most rare earths. These elements are valued for a variety of properties when alloyed with other metals: their magnetism, strength, heat resistance, or ability to act as a catalyst, for example. When used as phosphors, they create bright white light in compact fluorescent lamps and vivid colors in LCD screens.
Extracting the minerals from virgin ore is no easy feat because their similar chemical properties make it difficult to separate them. “You just don’t go mine for one or the other; you mine for all of them, you get them all, and they all come in different ratios depending on the mine,” says Tim Wilson, president and CEO of Arnold Magnetic Technologies (Rochester, N.Y.), a manufacturer of samarium cobalt magnets and a member of the Rare Earth Technology Alliance, part of the American Chemistry Council (Washington, D.C.). “If you had 100 kilograms of dirt from a really rich mine, out of that you would have 10 kilograms of rare earths—but you’d have all 17 of them, and you have to peel them apart like an onion.”
Rare earths aren’t scarce in a geological sense. With the exception of promethium, they are relatively abundant in the earth’s crust, but they tend to be found in low concentrations, making it challenging and expensive to mine and extract them. In short, the effort required to produce these materials is what transformed them from simply earths—their original name—to rare earths, and it wasn’t until the development of efficient separation techniques that the materials gained widespread use in industrial and commercial applications.
Until 2000, rare earths came from a variety of mines around the world, including the Mountain Pass open-pit mine in California, which dominated global rare earth production from the 1960s to the 1980s. Mountain Pass—now part of Molycorp Minerals (Greenwood Village, Colo.)—shut down in 2002 due to a combination of environmental restrictions and the appearance on the market of lower-priced rare earths from China. By 2010, China produced at least 95 percent of the world’s rare earths.
In 2011, however, China slashed its rare earth exports by some 40 percent, causing worldwide prices to surge. In mid-2010, for example, rare earth ores from China were about $14,500 a mt; a year later, the price had spiked to more than $100,000 a mt. Prices have stabilized considerably since then, but the previous price shock and the ongoing threat of shortages created a worldwide rush to find new ways to capture rare earths, including recycling them from electronic scrap.
Research and Recycling
The U.S. Department of Energy (WashÂington, D.C.) is one entity researching ways to recycle rare earths for commercial uses, with a focus on extracting dysprosium, neodymium, and praseodymium from commercial magnets and reusing them to make new magnet alloys. “We’re working on the science of developing the process—the best way to actually extract rare earths—and also determining what the recycled rare earths can be used for,” says Ryan Ott, the lead scientist on the project at DOE’s Ames Laboratory in Ames, Iowa. In a related vein, the Center for Resource Recovery and Recycling, a partnership of three higher education institutions with federal and corporate support that’s based at the Worcester Polytechnic Institute (Worcester, Mass.), is researching the recovery of rare earths from magnets, catalysts, phosphor dust from fluorescent light fixtures, and other secondary sources.
Commercial enterprises are delving into rare earth recycling as well. Creative Recycling Systems and GreenRock Rare Earth Recovery Corp., both in Tampa, Fla., have formed a joint venture to extract and reuse rare earth elements from cell phones, flat-panel video screens, fluorescent lighting, magnets, and industrial batteries. The venture processes material using a system from BLUBOX Trading (Birrwil, Switzerland) that shreds materials and recovers the rare earths while also capturing hazardous materials such as mercury. The BLUBOX essentially is “an environmentally enclosed, advanced shredding and separation system that will recover the phosphors from [each] unit and separate and sort the other elements—the glass, plastics, circuitboards, and metals—as well,” says Brian Diesselhorst, senior vice president of Creative Recycling, which owns exclusive North American rights to the technology. The phosphorous coating on the glass in fluorescent bulbs and LCD screens is made up of three heavy rare earth elements: europium, terbium, and yttrium, Diesselhorst says. Creative Recycling sends the material in phosphor form to refiners in Europe that separate and recover the mercury from the rare earths and sell the rare earth metals primarily to parts and bulb manufacturers.
Two other companies—AERC Recycling Solutions (Flanders, N.J.) and Global Tungsten & Powders Corp. (Towanda, Pa.)—have worked together since 2008 on a process to recycle rare earths from spent fluorescent lamps. AERC uses a mercury retort furnace at its Allentown, Pa., facility to remove and recover the mercury, creating a clean phosphor powder containing rare earths that Global Tungsten uses to manufacture a variety of products.
In Europe, Solvay (Brussels) has opened two facilities to recover rare earths from end-of-life equipment. The company collects and sorts used light bulbs containing cerium, europium, gadolinium, lanthanum, terbium, and yttrium, then it grinds them into luminescent powders. It ships the substances to its plant in Saint-Fons, France, which extracts the rare earth concentrate, then it sends the concentrate to a facility in La Rochelle, France, that separates the various rare earth metals. Once separated, the rare earths are reformulated into luminescent precursors used to make new bulbs.
Also in Europe, a joint venture of Umicore (Brussels) and Rhodia (La Défense, France), part of the Solvay group of companies, has developed a process for recycling rare earths from nickel-metal hydride batteries. The rare earths cerium, lanthanum, neodymium, and praseodymium constitute 7 percent of such batteries. A Umicore plant in Antwerp, Belgium, separates the rare earths from the batteries’ nickel and iron. The resulting high-grade concentrate then heads to Rhodia’s plant in La Rochelle, which refines it into rare earth materials.
In Japan, Honda Motor Co. (Tokyo) has joined with Japan Metals & Chemicals Co. (Tokyo) to extract rare earths from the spent Ni-MH batteries that power Honda hybrid vehicles. The venture’s process extracts an oxide containing rare earth metals from the batteries, then it uses molten salt electrolysis to extract metallized rare earths suitable for use as negative-electrode material in new Ni-MH batteries. According to Honda, the process recovers rare earth metals that are 99-percent pure—matching the purity level of “ordinary traded, newly mined rare earth metals”—and extracts as much as 80 percent of the rare earth metals in each Ni-MH battery.
Prospects for Recycling Rare Earths
Wilson of Arnold Metal Technologies makes the case that some rare earths are worth pursuing more than others. The 17 rare earth elements typically are classified into light and heavy rare earths, he explains. The light group includes lanthanum, cerium, praseodymium, promethium, neodymium, and samarium, and the heavy group includes terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. “There’s a lot of supply of light rare earths coming online, but the heavy rare earths are in short supply,” Wilson says. China is the only country producing them currently, and potential Western sources won’t begin production for years. Because there are limited reserves of these materials, they “are going to continue to be in short supply,” he says. “So if I were a recycler, I’d focus on figuring out ways to recycle heavy rare earths.”
That might be easier said than done, however. With electronics, for example, “the problem is getting [the magnets] out of the device—they tend to be smaller,” Wilson says. “Then there are all different grades of these materials, so you have to figure out a way to reprocess them—either remelt them or potentially go back to re-separating them to reconstitute them back as magnets. It’s not as easy as it might seem.” As Ott puts it, “obviously recyclers are [already] going after all the precious metals in electronics, but it’s questionable right now if the technology exists yet to economically recover the rare earths in there.”
One important question is whether recycled rare earths are of comparable quality to mined material. The Ames Laboratory’s initial work has indicated that “recycled rare earths show promising properties compared with pure rare earths for the intrinsic properties of magnet alloys,” Ott says. The laboratory has found, however, that recycling different grades of magnets from a variety of sources poses a challenge, he notes. “It’s as if a plastic recycler had every type of plastic being included in its feedstock.”
Other challenges pertain to identifying scrap sources of rare earths and establishing a recycling infrastructure for the materials. “Where is your scrap coming from?” Ott asks. “We know rare earth magnets are used in a large variety of applications—the amount used just in hard drives is mind-boggling. We know they’re used in wind turbines—there are hundreds of pounds in wind turbines. So the question is infrastructural, maybe even cultural—that’s the first thing you’d have to bridge” to make rare earth recycling as ubiquitous as, say, aluminum can recycling.
A Constantly Changing Market
The rare earth market has changed dramatically since China imposed export quotas on the material in 2011. Prices are down for virtually every rare earth that comes from China. Lanthanum oxide, which rose from $8.71 a kg in 2008 to $117 a kg in the third quarter of 2011, was selling for $11 a kg in January. Praseodymium, part of an alloy used in aircraft engines and welder goggles, was $18 a kg in 2009, peaked at $163 a kg in the first quarter of 2012, and sold for $85 a kg this January. Dysprosium soared from $118.49 a kg in 2008 to $2,300 a kg by September 2011 but had slipped to $630 a kg in January.
One reason for the decline is that new supplies of virgin rare earths are starting to reach the market. In 2011, Molycorp invested more than $1 billion to reopen the Mountain Pass mine. In addition, Lynas Corp. (Sydney) recently began shipping rare earths from its Mount Weld mine in Western Australia to the world’s largest rare earth processing plant in Malaysia, with most of the refined material destined for Japan.
Despite these new supply sources, the global supply of rare earths is likely to decrease in the short term. In January, China announced 2013 production quotas for rare earth-containing ore at about half the level of previous years, and experts foresee no great spurt in its production in the near future. “Given China’s rare earth export restrictions, the country’s rare earth export volume is bound to follow a downward trend,” says ProEdge Wire, an investor newsletter.
In terms of specific rare earths, Roskill Consulting Group (London) predicts that nearly 70 percent of global demand for rare earths will be for cerium and lanthanum, followed by neodymium (used mainly in magnets) and europium, terbium, and yttrium (used in phosphors and ceramics). Roskill expects magnet-related demand for rare earths, primarily for use in consumer electronics worldwide and electric bicycles in China, to grow 6 to 8 percent annually until 2016, with demand for rare earths in phosphors for fluorescent lamps also to grow 6 to 8 percent a year until 2017.
According to DOE’s Critical Materials Strategy Report, the United States faces serious supply challenges for dysprosium, europium, neodymium, terbium, and yttrium—minerals essential in many manufacturing sectors, especially those producing clean technologies such as photovoltaic cells and electric vehicle motors. Consequently, in January, DOE announced it would allocate $120 million over five years to establish the interdisciplinary Critical Materials Institute at its Ames Laboratory to “develop solutions to the domestic shortages of rare earth metals and other materials critical for U.S. energy security.”
Rare earth recycling could figure prominently among those solutions, despite its technical and infrastructure challenges. “We’re trying to use less rare earths now because of the possible limitations of rare earth supplies, but the reality is rare earths are used because—at the moment—they’re the best for many applications. We just don’t have a lot of alternatives in some cases,” Ott says. For Creative Recycling’s Diesselhorst, recycling rare earths makes sense to balance unstable primary supplies in the global market—and to reclaim the valuable resources. “We can’t rely on China,” he says. “Rare earths are difficult to mine for, but these materials are found in everyday consumer electronics. Recycling activities have to be focused on maximizing all the recyclables, not just the precious metals. To have 70 percent of the e-scrap enter landfills every year, it’s just—for lack of a better term—throwing valuable commodities into the dump.”
Theodore Fischer is a writer based in Silver Spring, Md.
Global supply worries and price volatility have motivated a variety of stakeholders to explore whether recycling rare earth metals is possible—or profitable.