Critical Elements' Supplies Worry US Scientists

A leading group of American scientists has joined together to urge the federal government  to secure future supplies of rare earths and other elements critical to the development of new technologies to ensure U.S. energy independence.

The call comes as efforts to develop new energy technologies intensify and China starts to control supplies of many critical elements.

"Our report outlines a plan that can help the U.S. take control of its energy future," says Robert Jaffe, professor of physics at the Massachusetts Institute of Technology and co-chair of the study group. "No country can mine its way to ECE (energy-critical elements) independence. Instead, we need to develop an integrated approach to securing supplies of these key materials."

The report is a combined effort by the American Physical Society (APS) and the Materials Research Society (MRS).

In general, the committee does not recommend that the federal government establish non-defense-related economic stockpiles of the critical materials, with the exception of helium.

Helium is found in economically viable quantities only in natural gas reservoirs, occurring at levels as high as 7 percent. Natural gas is extracted from reservoirs at a rapidly increasing rate with helium being vented to the atmosphere.

Helium liquefies at the lowest temperature of all elements and does not solidify, making it important for cryogenic applications.  Also, helium is the only element that cannot be rendered radioactive by exposure to radiation. Helium is also the fluid of choice for advanced nuclear reactor design.

Other critical elements include:

• Gallium, germanium, indium, selenium, silver and tellurium: All employed in advanced photovoltaic solar cells, especially thin-film photovoltaics.

• Dysprosium, neodymium, praseodymium, samarium and cobalt: Used in high-strength permanent magnets for many energy-related applications, such as wind turbines and hybrid automobiles.

• Most rare earth elements, valued for their unusual magnetic and/or optical properties. Examples include gadolinium for its unusual paramagnetic qualities and europium and terbium for their role in managing the color of fluorescent lighting. Yttrium is an important ingredient in energy-efficient solid-state lighting and lasers.

• Lithium and lanthanum: Used in high performance batteries.

• Platinum and palladium used as catalysts in fuel cells that may find wide applications in transportation. Cerium is also used as an auto-emissions catalyst.

• Rhenium, used in high performance alloys for advanced turbines.

A bill introduced by U.S. Sen. Mark Udall of Colorado (the Critical Minerals and Materials Promotion Act of 2011) makes recommendations similar to those found in the report.

"It's vital that we take steps today that will stabilize the market for energy-critical materials and ensure we have a sustainable supply in the future," Udall says. "The APS-MRS report and my bill provide a solid foundation that, when implemented, will help U.S. companies globally compete in emerging energy industries that are essential to strengthening U.S. economic and national security."

A focal point is a recommendation to establish a research and development effort focused on energy-critical elements and possible substitutes that can enhance vital aspects of the supply chain, including: geological deposit modeling, mineral extraction and processing, material characterization and substitution, utilization, manufacturing, recycling and lifecycle analysis.