Many were skeptical of Ucore Rare Metals Inc.’s claims that it had identified a technology that would revolutionize the way the notoriously tightly interlocked rare earth elements are separated. Less than two years later, however, the mineral explorer turned innovator has quieted some of this doubt by separating the most critical rare earth – dysprosium – from a solution derived from its Bokan Mountain REE project in Southeast Alaska.
Ucore achieved this feat with the help of Utah-based IBC Advanced Technologies Inc., a world leader in molecular recognition technology, a means of isolating a targeted material by binding with ions based on multiple parameters such as size, chemistry, and geometry.
This process is considered to be quicker and less complicated than the methods traditionally used to coax apart REE.
Ucore and IBC teamed up to build SuperLig-One, a pilot plant that employs the highly-selective MRT process to isolate rare earth elements suspended in a leach solution created while putting together a process flow-sheet for extracting the rare earths from the Dotson Ridge deposit at Bokan Mountain.
In the final phase of the trial run of SuperLig-One, the pilot plant produced 99.99 percent pure dysprosium from the solution.
“The isolation of Dy (dysprosium) at an advanced pilot scale has … been one of mission-critical objectives of SuperLig-One since the early-blueprint phase nine short months ago, and we’re excited to complete this mission in such a concentrated time frame,” said Ucore President and CEO Jim McKenzie.
Dysprosium prizeSince a REE-laden solution from Bokan Mountain was first pumped through SuperLig-One, the pilot plant has earned high marks in terms of purity and recoveries.
“The MRT (molecular recognition technology) platform has consistently outperformed traditional REE separation methodologies, including solvent extraction, ion exchange, and precipitation, based on critical metrics such as efficiency, recovery, and near-quantitative levels of purity,” McKenzie touted.
The process to extract pure dysprosium involved five stages:
• Separating the suite of rare earths contained in the pregnant leach solution from non-REE elements such as iron, thorium, uranium, zinc, copper, nickel, titanium, zirconium, and other trace base metals;
• Extracting the first rare earth by separating scandium from the other rare earths in the solution;
• Dividing the heavy rare earths, samarium to lutetium, and light REE, lanthanum to neodymium plus yttrium;
• Dividing the heavy rare earths into two subgroups, samarium-dysprosium and holmium-lutetium; and
• Finally, the extraction of nearly pure dysprosium.
Ucore said one of the amazing things is that through each step of the process, more than 99 percent purity for the groups, subgroups and individual rare earths was achieved at each stage; and nearly 100 percent of the REE were retained and available for the next stage. This means that virtually none of the rare earths were lost and the recovered rare earths are exceptionally pure.
Scandium, the first individual rare earth SuperLig-One extracted from Bokan Mountain feedstock, is a highly valued component of advanced aluminum alloys. Its electrical and heat-stabilizing qualities also make it a desired ingredient in the production of solid oxide fuel cells.
The big prize, however, is the separation of dysprosium.
“The recovery of near-quantitative purities of dysprosium at industrial scale, solely using American feedstock, and without the use of chemically-intensive SX technologies, are significant firsts for the industry,” said McKenzie.
According to a 2011 study by the U.S. Department of Energy, dysprosium is deemed the most critical of all elements in terms of its importance to clean energy and supply risk.
“This metal is deployed extensively in United States military, high technology and clean energy sectors, with 100 percent of the product currently originating from China,” the Ucore CEO said.
In fact, four rare earths – dysprosium, europium, terbium and yttrium – topped the list of DOE’s five most critical and supply risky elements.
The europium and terbium are the next REE to be separated from the Bokan Mountain solution.
The remaining heavy REE solution and the light REE solution with the yttrium will be retained for future work.
Beyond BokanUcore identified MRT during a search for an economic and environmentally sound way to separate the 16 tightly interlocked rare earths present at Bokan Mountain. What it discovered, however, is a potential game-changer that has implications well beyond the Southeast Alaska project.
The company envisions this cutting-edge rare earth recovery technology could be used to extract rare earths and other metals from coal ash, mine tailings, oil sands and recycled consumer and commercial products.
In July, Ucore announced a program to use SuperLig molecular recognition technology to bench-scale separations of rare earths and other technology metals from a leach solution derived from the tailings of an Alberta oil sands operation.
Ucore and an unnamed major Alberta producer will equally absorb the net costs of the project, after a C$220,000 grant provided under Canada’s Industrial Research Assistance Program.
“This high-profile project truly shows the versatility of SuperLig across a diverse range of feedstock alternatives, including not just in-situ mining facilities, but process-flow and tailings management facilities as well,” said McKenzie.
The separation of metals from the oil sands derived leach solution will take place at IBC’s Utah facility, which is where the SuperLig-One plant successfully separated 99.99 percent pure dysprosium from a solution sourced from Bokan Mountain.
Ucore and IBC also are looking beyond rare earths.
“The SuperLig portfolio now includes fully developed and customized separation molecules for almost all of the burgeoning clean energy and technology metals, specifically REE, lithium, cobalt, tungsten and PGM (platinum group metals),” said McKenzie.
“All told, the comprehensive portfolio represents a broad field of vision and a remarkable potential for rapid growth across multiple metals sectors, via a hub and spoke growth platform,” the Ucore CEO added. “That vision will apply to a potential multi-metal co-venture with IBC.”
With the successful maiden run of SuperLig-One now complete, the partners now have their sights set on the construction of a commercial-scale REE separation plant.