Endangered elements Critical thinking As our supply of some essential elements dries up, it’s time to start urban . Emma Davies reports

Serious threat in the next 100 years

Rising threat from increased use

Limited availability, future risk to supply


50 | Chemistry World | January 2011 www.chemistryworld.org Last October, China started Mike Pitts, of the UK’s Chemistry between the rate at which we’re In short building the world’s biggest off- Innovation Knowledge Transfer using materials and recycling,’ says shore wind farm in Bohai Bay, a few Network.  Supply of several Pitts. ‘We are making the elements hours from Beijing. The country Pitts and his colleagues have elements, including economically unrecoverable. You is constructing wind farms on an compiled an ‘endangered element’ , , get concentrations of in unprecedented scale – surely good where red elements and is waste streams that are higher than news given its insatiable appetite are under ‘serious threat’ of predicted to exceed the ores they are coming from.’ for coal. But each megawatt of becoming unavailable in less demand in the near future power a generates than a century (see facing page).  Rare used in Magnetic attraction requires up to one tonne of rare Helium is marked red, as are the and The rare elements (REEs) earth permanent magnets. The staples gallium and are not scarce, but are – the fifteen , plus elements used in the magnets indium. Meanwhile, the rare earth difficult to separate and and – are being – , and metals rank near the top of most purify consumed at alarming rates, partly – are in short supply and ‘critical’ lists.  The west relies on to feed our obsession with the the west is in danger of losing China to supply rare latest must-have technology. ‘The access to them as China’s domestic Action stations earths, but as China’s real gift of the rare earths has been needs soar. Western governments are domestic demand miniaturisation,’ says Jack Lifton, Unfortunately, the green future awakening slowly to the threat of grows, alternatives are who runs a US consultancy called of the UK and much of Europe also losing access to key elements and desperately required. Technology Metals Research. relies heavily on wind turbines rich expert panels in the EU and US  Recycling and Rare earths like neodymium and in rare earths. And it’s not just green have published lengthy reports. alternative sources are dysprosium are used to make small, technology that is under threat – Critical raw materials for the EU, being explored, but they lightweight, and incredibly strong many of our everyday electronic published in 2010, identified 14 may not arrive quickly magnets. From military high-tech items, from iPhones to LCD raw materials and groups, enough to plug the short gadgets to , magnetic televisions, depend on the same including all of the rare earth and term demand gap jewellery clasps and magnetic toys, critical elements. platinum metals, as well the rare earths have brought huge Rare earths are not the only as , beryllium, , benefits. elements causing supply concerns fluorspar, gallium, , Many green technologies are – elements such as helium (see graphite, indium, , heavily dependent on the REEs, Balloon about to burst? p53), , , and tungsten. especially wind turbines and hybrid phosphorus (see Taking the P, p54) The expert group that compiled cars; each Toyota Prius hybrid car and are beginning to slip the report would like to see ‘policy is reported to contain as much as from our grasp. actions’ to make recycling more A monument in a field of 1kg of neodymium in its motor and ‘The periodic table is a thing efficient and is keen to promote wind turbines in Damao, 10–15kg of in its battery. of real beauty to chemists but we research into recycling ‘technically China. The inscription Although the metals are not all are staring at the possibility of not challenging’ products. reads: ‘The home of rare that rare, they are only found – being able to access parts of it,’ says ‘There’s currently an imbalance earths welcomes you’ lumped together – in particular REUTERS www.chemistryworld.org Chemistry World | January 2011 | 51 Endangered elements The screen ‘Indium is one of the most critical elements cells and flat panel displays. ‘There is more indium and gallium in use because of the way that we use it,’ says Mike The Earth’s crust contains roughly three than in proven possible reserves,’ says Pitts, from the UK’s Chemistry Innovation times as much indium as , although silver Roger Morton from UK recycling specialists Knowledge Transfer Network. For example, can be mined far more efficiently. In 2007 the Axion Consulting. ‘So it’s more interesting to every display screen contains US Geological Survey estimated that we will mine stuff around you than mine it out of the indium components. run out of indium for extraction in less than two ground,’ he says. About 45 per cent of all indium extracted is decades, although the indium industry tends to Recycling the indium from spent technology used for the indium that lines solar dispute such figures. holds an obvious appeal but industry is reluctant to invest. C-Tech innovation, a UK technology development company, was part of a recent project to recycle flat screens and THINKSTOCK recover liquid , , and indium using an -leaching process. ‘We have the technology which will work to recover the indium from screens, but at the moment it’s not economically viable,’ says Ian Holmes, project manager at C-Tech. ‘The price of indium is less than half of what it was when we started the project three years ago,’ he says. The project highlighted several recycling issues, not least the differing internal makeup of seemingly identical devices. ‘There’s a long list of issues to be addressed,’ says Holmes. In the past couple of years, Axion has had interest from some major Asian electronics manufacturers looking to set up segregated EU recycling schemes for their branded products, says Morton. The idea is that the companies would stay in touch with those who had bought their technology and after a few years offer a deal on a new model in exchange for the old. Although such schemes would boost sales of new products, the ‘prime driver is to get the resource back,’ says Morton. ‘It’s much easier to recycle a stream of identical Apparently identical screens can be different inside, making recycling more difficult computers of a single brand.’

regions of the Earth’s crust. Their their unique electrical and magnetic similar chemical properties make properties and there is no substitute them difficult and expensive to for them,’ he says. separate from one another. Not only are they becoming harder to mine Heavy heart but the few nations that do mine Demand is predicted to outpace them are clutching their precious supply for the so-called heavy rare resources ever tighter. earths dysprosium and terbium in China has 37 per cent of the little more than a decade, perhaps world’s accessible reserves, less. Not only are the elements according to the British Geological harder to extract than the light Survey (BGS), followed by the REEs, but all of the world’s heavy former Soviet Republics that rare earths are mined in China. make up the Commonwealth of Dysprosium and terbium are Independent States, then the US ‘miracle ingredients of green and Australia. But China supplies energy products,’ says Lifton. Very about 96 per cent of the world’s small amounts of dysprosium give REEs, according to the BGS. In magnets that are up to 90 per cent recent years it has started to cut rare lighter, while terbium can cut the earth exports and is expected to electricity consumption of lights limit exports to finished products, by up to 80 per cent. Alloying according to the US Government neodymium with terbium and Accountability Office (GAO). dysprosium preserves the magnetic Lifton is alarmed by the slow pace properties at the high temperatures with which western governments of hybrid car engines and wind are dealing with the supply situation. turbines. The high temperature ‘These metals are not used for their magnets need considerably more

ISTOCKPHOTOS structural value – they are used for dysprosium relative to neodymium

52 | Chemistry World | January 2011 www.chemistryworld.org Balloon about to burst? Helium may be the second most abundant element in the universe, but here on earth this is rare and precious. The only element to remain liquid at , its two stable , helium-4 and helium-3, are essential and irreplaceable mainstays of cryogenics. 4He can supercool magnets down to about 1.8K, and 3He goes really low – down to below 1K. For years, US government stockpiles have created the illusion of an abundant supply of 4He and an adequate supply of 3He, but recently growing worldwide demand and short-sighted management have shattered the illusion. Global demand for 4He is climbing as emerging powers such as China and India step up helium-hungry activities.Yet, despite the small supply and the growing demand, helium is cheap – a helium filled party balloon costs just a few dollars, for example. This is because the US government, which controls the Fort Knox of helium – the US National Helium Reserve near Amarillo, Texas – has been selling it off at bargain basement prices. The cheap price means that this precious Artificially cheap prices and poor resource management could spell the end of the party balloon resource has been squandered, according helium-filled balloon should cost $100. Spurred the heavy- used in thermonuclear to Nobel laureate Robert Richardson, on by recent National Research Council warheads. Thanks to the cold war arms race, who discovered liquid helium’s superfluid recommendations to sell 4He at market prices, the US has had a steady and adequate supply. properties. At the current rates, ‘the world the US government announced in August that But after the terrorist attacks on would run out in 25 years, plus or minus five prices will increase by 15 per cent in 2011. 11 September 2001, US national security years,’ he told a gathering of Nobel laureates 3He is critical for European Organisation for agencies began using 3He in nuclear detectors in August of this year. Nuclear Research (CERN) in Switzerland, and that were installed by the thousands at 4He can be recycled, but with prices so low, other scattering facilities. The airports, shipyards and border crossings. there is little incentive. The price needs to has also revolutionised lung imaging, and These scanners now account for 80 per cent rise by 20- to 50-fold to make recycling worth it is used in oil and gas exploration. 3He is a of US consumption of the gas. while, according to Richardson, who says that a byproduct of the of tritium, Rebecca Renner

than is found in the ores. its rare earth mine in southeast The Chinese think they are Alaska, which could produce running out of dysprosium and significant amounts of dysprosium. terbium, explains Lifton. China has several mines under currently produces about 900 development. The problem with all tonnes of dysprosium per year of these is that the start-up costs are and estimates that it can mine high but the mines are small, with a further 13 500 tonnes. So at limited revenues, says Lifton. ‘So the current consumption rate, either you subsidise them or you the country could run out of the get the end-user industry to put the element in 15 years. But given the money in and develop them.’ soaring demand, reserves could be Mountain Pass in California, exhausted even sooner. US, was once the largest rare earth ‘If we want electric cars, we mine in the world – but ceased had better start producing some production in 2002, partly because dysprosium, because the Chinese of Chinese businesses undercutting won’t keep supplying it to us,’ adds prices. Now US company Molycorp Lifton. ‘My guess is we’re going is set to reopen the mine in 2011, to be short of dysprosium before and by 2012 expects to be mining anyone gets a solution rolling.’ and separating , lanthanum, The US GAO has reported that it , and neodymium may take up to 15 years to rebuild a at full capacity. The mine rare earth supply chain in the US. will do much to ease the current Industry is onto the problem but pressure on neodymium supplies. time is running out. Yet Mountain Pass will not Countries with reserves are initially be able to refine the rare scrambling to open mines. In earth oxides into raw materials and July 2010 US company Ucore will probably have to ship them Rare Metals started drilling at to China. Refined rare earths are www.chemistryworld.org Chemistry World | January 2011 | 53 Endangered elements

causes the structure to swell,’ explains Taking the P Williams. ‘The surface swells but the Modern agriculture depends on phosphorus, which Yet phosphorus is relatively easy to recover inside doesn’t, creating stresses that is mostly obtained from mined rock. from systems. Every year the global cause the material to break apart.’ Phosphorus is typically combined with , population excretes around three million Williams has managed to make new and potassium in fertilisers. Scientists with tonnes of phosphorus in urine and faeces and magnets by pressing the resulting the Global Phosphorus Research Initiative estimate highly populated cities have been described as powder together and heating it. The that within 30 to 40 years there won’t be enough phosphorus hotspots. If urine can be kept separate magnets are not top-spec but can phosphorus from mining to meet agricultural from the rest of the sewage, it can be applied be used in motors. ‘We can also add demand, and predict a global peak in 30 years. straight to the fields. In some parts of Sweden, all extra neodymium and dysprosium new toilets must be able to divert urine for storage and change it to a different grade of and use by local farmers. material,’ explains Williams. ‘We UK water company Thames Water is building a want to take it to the next step where ‘nutrient recovery facility’ to remove a compound we’re actually collecting scrap and called struvite, which contains phosphorus and reprocessing it into magnets.’ , from sewage at its works in Slough. The Meanwhile, researchers at the plant is scheduled to begin operations in mid-2011. University of Leeds, UK, have found The phosphorus extracted from Slough’s a way to reclaim rare earth oxides wastewater is predicted to form 150 tonnes of cheaply from the waste stream phosphate fertiliser pellets per year which can be from refining . The spread directly onto soil. titanium dioxide industry ‘hates’ the The struvite blocks pipes and causes water rare earths that contaminate their companies real headaches. ‘This project is feedstock, explains project leader a classic win-win,’ says Piers Clark, Thames Animesh Jha. Water’s director of asset management. ‘We Rare earth have

BRYCE RICHTER, UNIVERSITY OF WISCONSIN-MADISON, US WISCONSIN-MADISON, OF UNIVERSITY RICHTER, BRYCE solve a costly problem and in so doing provide a extremely high boiling points, thanks Phosphorus can be reclaimed from wastewater renewable form of phosphate.’ to strong nuclear forces. Working with UK company Millennium Chemicals (now Cristal Global), currently only available from China says. There are projects to reduce Jha’s team set about trying to purify and US industry officials have told and recycle rare earths. When lower grade titanium tetrachloride the GAO that it would take at least computers are discarded the hard feedstock. The process that they came two years to develop a pilot plant that drives are dismantled so as to destroy up with involves roasting aluminate could refine the oxides to metals. any data. Andy Williams’s team at materials with alkali. ‘During roasting the University of Birmingham, UK, the dispersed rare earth There is a light Praseodymium, cerium, has found a neat way to turn their flocculate in the highly alkaline So far, so gloomy. Yet Pitts sees the lanthanum, neodymium, neodymium magnets into powder, medium,’ explains Jha. The metal situation as a ‘huge opportunity’ for and simply by exposing them to hydrogen oxides – of neodymium, cerium, chemists to help recover the elements. oxides – their similar gas at atmospheric pressure. lanthanum and praseodymium – ‘We should be scared but equally properties make them ‘Hydrogen goes into the spaces form a separate layer that floats excited about the opportunities,’ he difficult to separate between the neodymium atoms and despite its high , thanks to repulsion between the OH groups surrounding the metals. ‘Our titanium dioxide process has a very low carbon footprint compared to the standard acid leaching process,’ says Jha. Jha is currently seeking funding for the next project stage – separating out the component rare earth oxides. The rare earth oxides all have very similar properties and Jha has a difficult task in store. We all have a difficult time ahead and it is hard to see how short-term shortages of rare earth elements will be addressed. Let’s hope that the wind of change will blow across the West and give scientists the intellectual and financial boost needed for a recycling revolution.

Emma Davies is a freelance science writer based in Bishop’s Stortford, UK Additional reporting by Rebecca Renner, a freelance science writer


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