Breakthrough process recovers REEs from coal waste, magnets Metal Tech News – February 10, 2021
American Resources Corp. has acquired exclusive rights to potentially game-changing rare earth and critical elements separation and purification technologies from Hasler Ventures LLC and Purdue University.
These technologies developed in the laboratory of Linda Wang, a professor of chemical engineering at Purdue, are designed as a highly efficient and environmentally sound method to separate and purify rare earths and other critical elements from coal, coal byproducts, recycled permanent magnets, and lithium-ion batteries.
Joe Pekny, a Purdue professor of chemical engineering, believes the REE and critical mineral separation processes developed by Wang offer a sustainable and economical path for the United States to re-enter the rare earth metals market.
"What's exciting is that the U.S. has the rare earth metals to meet the growing demands of the U.S. market and other markets around the globe and reduces our dependence on foreign sources," he said. "Linda's method replaces a very inefficient process and replaces it with an earth-friendly, safe extraction process."
American Resources investors agree with Pekny's assessment. American Resources stock has rocketed more than 300%, from $2.50 per share on Feb. 1, the day before Purdue announced that American Resources acquired the technologies, to $7.72 per share at the open of trading on Feb. 9.
The reason for the excitement amongst scientists and investors alike is this technology has the potential to convert environmental liabilities such as coal ash storage areas, acid mine drainage, and discarded magnets into new sources of rare earths and critical elements.
Rich REE sources
The group of metals known as rare earths include the 15 elements in the lanthanide series near the bottom of the periodic table, plus scandium and yttrium, which have similar properties and are almost always found with the lanthanides.
These 17 elements are essential ingredients for magnets, metal alloys, polishing powders, catalysts, ceramics, and phosphors. While all high-tech sectors are finding new and increased applications for the special properties offered by these rare earths, the elements used in powerful permanent magnets that go into electric vehicles and wind turbines are particularly in high demand.
"About 60% of rare earth metals are used in magnets that are needed in almost everyone's daily lives. These metals are used in electronics, airplanes, hybrid cars and even windmills," Wang said.
The global rare earths market is estimated at roughly $4 billion and is growing at 8% per year.
Enormous domestic reserves of rare earths are found in the coal that has been burned to generate electricity in America for decades. Though unmined coal deposits typically do not have high enough concentrations of REEs for economic recovery, the burning of this fuel works like a concentrator that leaves behind higher grades of these technology metals in the ash.
"Coal ash is rich in rare earth elements, as rich as some of the ore deposits," said Wang. "The United States produces about 129 million tons of coal ash every year."
In recent years, nearly half of this coal ash is recycled as fill for abandoned mines; an ingredient in concrete; gypsum in sheetrock and other wallboard; and an agricultural soil additive.
With more than a century of coal-fired electrical generation, however, there are billions of tons of REE-bearing coal ash that have simply been buried or stored in containment facilities in the U.S.
Over the past five years, American Resources has acquired more than $300 million worth of coal assets and related infrastructure, primarily in Kentucky, that could provide sources of REE-bearing coal ash.
American Resources also envisions waste magnets as an incredibly efficient feedstock for Wang's REE separation technologies.
Containing more than 25% rare earths oxides – dysprosium, neodymium, praseodymium, samarium, and terbium – REE magnets are considered a super grade ore with a simple mineral compound.
Widely used in consumer electronics, it is estimated that roughly $3 billion worth of rare earths ends up in landfills each year.
Thus, the recycling and recovery of the rare earths from these permanent magnets in speakers, hard drives, electric vehicles, magnetic resonance imaging (MRI) machines, wind turbines, and other products could offer another domestic REE supply while reducing waste headed to landfills.
Cleaner, greener tech
Whether they are sourced from heaps of coal ash, recycled magnets or naturally occurring geological deposits – the 17 rare earth elements are extremely difficult to separate due to their identical ionic charge and very similar size.
The traditional method of separating these rare earths into individual metals is known as solvent extraction, which involves a long and complex process that uses numerous chemicals.
"Typically, old technologies from the 1950s are used for separation and purification," said Wang. "They usually require 1,800 different extraction stages in series and in parallel for purification. Such processes can be hazardous, costly and inefficient."
Seeking a more environmentally sound and efficient means to extract these technology metals from coal ash, Wang developed new processes for separating rare earth elements first from other impurities and then from each other in just a few steps.
These processes utilize chromatography, which involves the use of substances that cause the various components of a mixture to flow at different speeds, to separate the notoriously tightly interlocked rare earth elements.
Wang and her team at Purdue refined the process, known as ligand-assisted displacement chromatography, to produce rare earths with purities topping 99%, while also capturing more than 99% of the available rare earths.
The ligands used to achieve these results are readily available and low-cost. The primary material used for this purpose is titania, a naturally occurring oxide of titanium.
As a cleaner and greener means of separating and purifying rare earths, Wang's ligand-assisted displacement chromatography provides a triple benefit to the environment when applied to coal waste and byproducts – cleanup decades of coal waste, no toxic solvents used in the production of rare earths, and a source of REEs needed by the EV and renewable energy sectors.
Wang's work has earned her praise from her colleagues.
"We've long been proud of Professor Wang and her research," Purdue University President Mitch Daniels said. "If this comes to fruition, it could be a very vital new asset in protecting our country's national security and manufacturing competitiveness."
Exclusive licenses
American Resources, who wants to bring Wang's lab work to commercial fruition, has licensed the ligand assisted displacement chromatography patents and know-how from Hasler Ventures.
"It is our shared belief that to compete in the world markets and to establish a robust domestic source of rare earth metals, the United States cannot solely rely on the current costly and environmentally harming methods of solvent-based extraction," said American Resources CEO Mark Jensen. "Linda Wang's method represents this path."
Founded by Dan Hasler, who retired from Purdue University in March 2020, Hasler Ventures is a Florida-based company founded in partnership with Purdue to commercialize the patented ligand-assisted chromatography rare earth separation technology.
"Linda has dedicated more than 10 years of research to developing this process and her innovation is one of the most promising and environmentally safer methods to separate and purify rare earth metals," Hasler said. "There is a lot of interest in this technology because it could support the U.S. domestic supply chain to more safely purify this critical resource currently done almost exclusively in China, which makes us dependent on them even though we have the raw materials available in the U.S."
American Resources' agreements with Hasler Ventures come in the form of two exclusive licenses:
• Technologies for the separation and purification of rare earths from coal, coal byproducts, coal waste and acid mine drainage.
• Technologies for the extraction and purification of rare earth and critical elements from used or waste permanent magnets and batteries.
American Rare Earth LLC, a wholly owned subsidiary of American Resources, plans to use the exclusive patents and technologies developed at Purdue to further develop much needed and environmentally safer rare earths and critical minerals supply chains in the U.S. The company already has several REE projects in eastern Kentucky.
"We're excited about partnering with American Rare Earth and American Resources on the implementation of our research," said Wang. "We look forward to working with their team on the design of a pilot production facility and an eventual full-scale production plant."
This team will include William Smith III, a chemical engineer that is very familiar with the chromatography process from his 33-year career of overseeing technical support for Eli Lily's global manufacturing facilities.
"The chromatography technology developed by Purdue for this process is one that I am confident will be successful given my years of experience in the field," said Williams, a distinguished alumnus of Purdue. "Our goal is to demonstrate globally that we supply the electrification market with isolated pure rare earth elements from domestic sources."
In addition to implementing the REE separation technologies for its own use, American Resources has committed to a three-year sponsored research program with Purdue and Wang to continue advancement of the technologies. In addition, Hasler will represent American Resources in subsequent sub-licensing and partnership opportunities and as an advisor to the company.
"Working with Purdue and Hasler Ventures to commercialize such an impressive suite of technologies that are of major importance to national security and the growth of the electrification marketplace is an honor for our company," said Jensen. "Their teams have been nothing short of amazing, as they have fully embraced the need to rapidly scale to a commercial process to produce rare earth and critical elements from available domestic sources."
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