Rare Earth Processing: A Complicated Proposition

(Casper Star Tribune, September 27) – Mining and processing rare earth elements is a particularly complicated endeavor. Unlike other minerals such as gold and silver, rare earth elements can’t be removed from the ground and with little effort formed into a final product.

Complexities stem first from the fact that rare earths are actually a group of 17 elements that naturally occur together. Each of the 17 are used individually or in combination with another for various products ranging from super magnets to laser guided missiles. That means the elements, which aren’t obvious to the naked eye, must be separated out from each other and the rock where they reside.

Most of the world’s rare earths currently come from China. But Wyoming’s northeast corner holds another major deposit. A Canadian company, Rare Element Resources, hopes to mine the elements, creating the country’s second rare earth mine and moving the U.S. away from its independence on Chinese minerals, said Jaye Pickarts, the company’s chief operating officer.

While the first stages of processing will be done in Wyoming, most of the world’s rare earth refining facilities are in China.

The U.S. developed some of the original refining technology decades ago. Overtime the process became expensive relative to Chinese miners and refiners. Environmental issues also forced the temporary halt of operations in the early 2000s at the Mountain Pass Mine in California, said Luisa Moreno, a research analyst who specializes in rare earths with Euro Pacific Canada.

Other countries, including the U.S., have recently spent millions of dollars trying to improve the technology.

“Molycorp built a new state of the art refinery facility with a chlor-alkali plant to recycle waste water and reagents,” Moreno wrote in an email. “Once commissioned, the new plant at Mountain Pass is expected to be more efficient, economically competitive and environmentally friendly, with a price tag however of over $1.5 billion to date.”

Molycorp, the only operational rare earth mine and refinery facility in North America, can refine some elements. There are also processing facilities in Europe, Japan, India and a number of other Asian countries, but China has most of the world’s capacity and expertise, Moreno said.

“China has the largest heavy rare earth reserves. These elements are the less common rare earths elements. Approximately 1 percent of what Molycorp produces are the heavy rare earths elements,” she said. ““That said, it’s an existing technology. And if Rare Element Resources decides to refine most elements in Wyoming, there’s likely no major processing challenges that with money and time they wouldn’t be able to solve.”

Rare Element Resources has had interest from companies around the world in its bulk product, but can’t yet say who they are going to sell it to. The company hopes, in the short term, to send its materials to refining facilities outside of China, Pickarts said.

“We want to build our own separation facility,” Pickarts said. “So we’re not at the mercy of a third party separator.”

The basic rare earth mining process in the Black Hills would start by removing rock from the ground and crushing it in a nearby building. That gravel would be trucked to a processing center in Upton, ground into a powder and leached with acid to dissolve the rock and separate impurities such as iron, manganese and aluminum.

All 17 rare earth elements, some in larger quantities than others, would then exist in super fine powder, Pickarts said. At that point, the company must find a buyer who would then separate and individually process the elements.

Rare Element Resources could develop its own refining and separation facility one day, Moreno said.

But in the meantime, they will need to sell it to whoever is interested.

Original article here.