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RECLAIMING RARE EARTHS 66 E&MJ; • OCTOBER 2017 www.e-mj.com tation based on an SEM-EDX analysis of Fire Clay fine coal refuse. It reported, "Unliberated monazite particles with an REE content of around 60% were discovered having particle sizes less than two microns." Flotation release analysis found heavy REEs "were like- ly associated with finely dispersed ash materials within the organic matrix. (M) aximum REE content occurred in par- ticles with an ash content of around 80%." The group recommended column flotation at a pH of nine and grinding for 60 minutes. Such reports add to a growing body of knowledge on the possibility of profitable REE extraction from coal. Concurrently, the federal government observed, con- ducted its own research, and is increas- ingly putting skin in the game. Government Involvement Recently, the Department of Energy's (DOE) National Energy Technology Lab- oratory (NETL) announced the results of multiple in-house projects centered on sampling and processing optimization. One of the highlights was the suc- cessful development of a procedure to arrive at accurate concentration data. Conventional methods were assessed for determining the markers, overlays, and interferences that caused a couple of the elements, such as scandium, to be reported at inaccurate concentrations, Mary Anne Alvin, REE technology manag- er, NETL, said. "Depending on what lab- oratory you go to, you may get the same concentrations for cerium, lanthanum, gadolinium or other REEs plus or minus some variation," she said. "NETL worked out a better set of procedures to be able to obtain the best concentration data rel- ative to whatever your sample is." Those procedures are available to researchers and miners on the NETL website. A separate NETL project arrived at a REE recovery process for acid mine drain - age. "External researchers are recover- ing nearly 100% of all the REEs," Alvin said. "When you think about cleaning up or adding value to a waste product, ex- tracting REEs out of acid mine drainage sludge, you've got to see that as a win." Currently, NETL is developing com- putational fluid dynamics modeling for REEs extraction from clays using ammo- nium sulfate, Alvin said. "You can design your reactor, change the parameters of your reactor, change your feed and pro- cess conditions," she said. "And by doing this, you can save time and cost, ironing out many of the problems before you ac- tually go into full design, construction and operation." NETL assigns its projects a technical readiness level, a score based on degree of development of the subject technology or process. "The fundamental work being done at NETL's in-house research is more on the lower TRL levels, maybe two or three, possibly four," she said. The DOE funding opportunities now available are for projects that would end at a five or six, she said. In June, the DOE's Office of Fossil Energy announced three funding oppor- tunities for research into processing tech- nologies potentially capable of producing salable REEs from coal, byproducts and waste. Targeted are REEs from the lan- thanide series (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), including scandium and yttrium, Jess Szymanski, DOE spokeswoman, said. "Of particular interest are the REEs that have been defined as critical elements: Nd, Eu, Tb, Dy and Y." The opportunity will allot $1 million apiece to three corporate entities. Equi- nox Chemicals was selected to conduct lab testing and produce a technical design for a plant to process byproducts from an ex- isting eastern Kentucky coal preparation plant. Inventure Renewables was selected to do the same using coal-related materi- als from an eastern Pennsylvania anthra- cite mine. Marshall Miller & Associates was selected to do the same with byprod- ucts from a West Virginia coal preparation plant. Success brings increased competi- tion for a possible second round of fund- ing to further develop initial plans. The focus is to validate the feasibil- ity of prototype REE separation and ex- traction systems, Szymanski said. The goal is to have an operational plant with- in a couple of years. "Validation is to demonstrate production of 10 pounds per day of at least three rare earth elements, as oxides, that are present in concentra- tions that are 90%-99% pure," she said. "After that, advancements and improve- ments in efficiency and optimization of either the equipment, technologies and/ or overall systems will follow." Many of the technologies and sys- tems are already established. Inventure Renewables, for example, will be using an ion exchange process that is based on the one used to separate uranium for the Manhattan Project. "What our partners have done is refine that pro- cess from a batch process to a continu- ous process," Anthony Marchese, chair- man, Texas Mineral Resources Corp. (TMR), said. TMR is part of the consor- tium that includes Inventure, K-Tech- nologies and Penn State. "What it does is it saves a tremendous amount of time, and it is way more efficient to do it on a continuing basis rather than a batch process." TMR will process coal overburden into a purified liquid solution, which will serve as a feedstock for continuous ion exchange, continuous ion chroma- tography (CIX/CIC). The primary target is scandium. Currently, roughly 10 tons of scandium are produced globally per year. Commercial applications include laser crystals and minor aerospace com- ponents. "We will also target the REEs that have higher market values, which tend to be the magnet-related elements, things like dysprosium and neodymium," Marchese said. "When we actually pro- cess it, we will determine which material we want to selectively extract." Currently, TMR likes its prospects, he said. "We are using a process that has been tested over time," Marchese said. "We are confident that if we can produce a purified liquid solution, we can separate it and extract the REEs." In August, the DOE announced a $17.4 million second-phase funding opportunity for four projects to test plans and designs for bench-scale and pilot-scale technolo- gy for REE separation and extraction from coal and its byproducts. Three of the four recipient projects are run by state universities. A University of North Dakota project could receive $2.75 million to test its system that uses lignite as feedstock. The West Virginia Univer- sity Research Corp. could receive $2.66 million to test its system that uses acid mine drainage solids. The University of Kentucky Research Foundation could re- ceive $6 million to test a pilot plant that uses coal washing byproducts and dry, fine coal. Technology solutions company Physical Sciences Inc. could receive $6 million to test its system that uses fly ash. Roughly six weeks later, DOE Secretary Rick Perry visited Inventure Renewables'