ABSTRACT
Among the current major rare earths consumers, United States, Japan, and the European Union are concerned about the rare-earth element (REE) supply, considering that the elements are vital input to materials and devices that support and sustain industrial economy apart from military technology and clean energy initiatives. The US Department of Energy (DOE) commissioned a study to determine which periodic elements are essential to maintaining the integrity of the United States, where key and critical materials were identified (USDOE 2010). Nine of the 14 key elements are REEs. The European Union undertook a similar exercise, and the results are the same. The REEs receiving “key” designations include lanthanum, cerium, praseodymium, neodymium, samarium, europium, terbium, dysprosium, and yttrium. The five other key elements are elements scattered throughout the periodic table and include lithium, cobalt, gallium, indium, and tellurium. “Critical elements” are a selection of the key elements that are necessary for clean energy technology production and have even greater supply risks than the key elements. The key elements conferred with the critical designation in the short term (0-5 years) were dysprosium, neodymium, terbium, europium, yttrium, and indium. Critical materials in the medium term (6-15 years) include dysprosium, neodymium, terbium, europium, and yttrium. All of them are REEs. The same US DOE report has even outlined a strategic plan to explore substitution of key and critical elements in future technologies, recycling from waste electronics, and development of a globally diverse supply of these elements. Out of these three options, the last one will provide a lasting solution if adequately supported by the first two options.
