|
Mining News: Refining rare earths Ucore pioneers new method of separating REEs into high purity salts Shane Lasley Mining News
Ucore Rare Metals Inc. has reached another milestone in its quest to separate rare earths into the individual elements needed in high-tech devices.
In testing molecular recognition technology, a proprietary method of separating rare earths developed by Utah-based IBC Advanced Technologies, the rare earths found at Ucore’s Bokan Mountain project in Southeast Alaska have been segregated as individual salts exceeding 99 percent purity.
“MRT offers a means of separating REEs to high purity in a rapid and cost effective manner, and with an exceptional level of selectivity and precision,” said Ucore President and CEO Jim McKenzie.
The avant-garde technology could turn the company into a front-runner in economic and environmentally sound rare earth separation worldwide.
“It’s very gratifying to see the fruition of this work and achieve such a high level of success. It is exciting to think of the business opportunities this can create for Ucore and for Alaska,” said Ucore COO Ken Collison.
Sen. Orrin Hatch, R-Utah, says opportunities offered by MRT could touch numerous industrial sectors across the United States.
“This breakthrough represents advanced American technology being used to address a uniquely American challenge. Securing the most critical specialty metals is essential to fuel our nation’s technology engines,” said Hatch. “Rare earths such as dysprosium, terbium, and neodymium are increasingly important to U.S. military, transportation, medical, and super-computing applications as we compete across the globe.”
Three-step process The MRT process is designed to bind selectively with ions based on multiple parameters such as size, chemistry, and geometry. Conventional technologies such as ion exchange, solvent extraction and precipitation generally recognize differences between ions based only on a single parameter.
MRT can separate tightly interlocked rare earths into individual salts in three steps, an achievement that took up to dozens of phases using forerunner technologies.
The basic idea behind the MRT process is that certain resins, known as SuperLig® resins, grab ions based on a number of traits. The technology has already been proven in mining, especially for applications in platinum group metal recovery and removing bismuth impurities from copper.
In creating a REE separation process for Ucore, IBC created resins specifically to bind to the parameters of ions associated with rare earths.
Using a pregnant leach solution prepared from material taken from the Dotson Ridge deposit at Bokan, IBC developed a three-step process for creating nearly pure rare earths.
In the first step, scandium and cerium were extracted. The remaining rare earth elements were then separated into two groups roughly defined as heavy and light rare earths. A final step caused the mixtures to separate into individual rare earth salts. Individual rare earths are cleaned from the SuperLig® resin columns with a small amount of acid.
The technique created 99.9 percent pure dysprosium and neodymium salts and a 99.1 percent pure terbium salt. All three of these heavy rare earth elements are considered critical to military, high-tech and green sector applications.
“Among other firsts, this is the first time that high-purity dysprosium has been generated in the U.S. using American feedstock. What’s more, the accomplishment was made without the use of traditional solvent extraction, a technology long known for the generation of unavoidable environmental pollutants,” said Jack Lifton, principal co-founder of Technology Metals Research and consultant to Ucore.
The new process also recovered more than 99 percent of the REEs available in the pregnant leach solution.
The MRT breakthrough is another advance in the Bokan Mountain project becoming a domestic source of heavy rare earths.
“In my opinion, Ucore now has the opportunity to both extract and purify heavy REEs completely within the U.S. This is a remarkable win for American technology independence from China,” said Lifton.
Exclusive rights To further strengthen Ucore’s foothold in the rare earths sector, the company has cut a deal with IBC for exclusive rights to the SuperLig® REE separation technology.
Upon delivery of a fully functional pilot plant, Ucore has agreed to pay IBC US$2.9 million for the rights to the potentially sector-changing technology.
“This is an important step for Ucore in obtaining the capabilities of an integrated provider of rare earth products from mine to metal,” Ucore’s McKenzie said March 3 in announcing the agreement.
“Perhaps most importantly, our licensing arrangement includes the application of SuperLig® technology to the world recycling and tailings processing sector – both for the recovery of rare earths and all other metals,” he added.
Under the agreement, Ucore will hold 60 percent interest in a joint venture with IBC to market and sell the REE separation technology to others.
“My congratulations to Ucore and Utah-based IBC Advanced Technologies, Inc. for delivering a prospective ‘missing link’ in the domestic technology metals supply stream,” commended Hatch.
Feasible mining While critical, rare earth separation is only one part of the equation when it comes to securing a domestic supply of REEs – mining is another.
A preliminary economic assessment completed for Ucore in 2012, envisions the production of 2,250 metric tons of rare earth oxides per year during the first five years of full production; including an annual output of 95 metric tons of dysprosium oxide, 14 metric tons of terbium oxide, and 515 metric tons of yttrium oxide.
The PEA predicts a pre-tax net present value of US$577 million, at a 10 percent discount rate; an internal rate of return of 43 percent; a payback period of 2.3 years; and an 11-year mine life.
A feasibility study currently underway will benefit from the new recovery process and an updated resource estimate based on drilling completed since 2012, including 3,960 meters in 2014.
A 2013 resource update for the Dotson Ridge deposit, not included in the PEA, outlines an indicated resource of 2.9 million metric tons averaging 0.614 percent (39.7 million pounds) total rare earth oxides and an inferred resource of 2 million metric tons averaging 0.605 percent (26.6 million lbs.) TREOs. Roughly 40 percent of the TREOs are the higher valued heavy rare earths.
A 17-hole drill program completed in 2014 included 12 infill holes aimed at confirming the resource and five deeper holes.
Ucore said 10 of the confirmation holes cut significant mineralization, including 2.42 meters grading 1.03 percent TREO; 2.76 meters grading 1.65 percent TREO; 3.37 meters grading 1.9 percent TREO; and 2.88 meters grading 1.12 percent TREO.
The deep drilling tapped similar widths and grades some 100 meters below any previous intercepts. With the current resource extending only to an average depth of 220 meters, this evidence that the deposit runs deeper shows the potential for adding years to the life of a heavy rare earths mine being planned for Southeast Alaska.
The final blueprint of what that mine might look like will be outlined in the feasibility study due out later this year.
| 