The SuperLig®-One pilot plant (the “Plant”, “Pilot Plant” or “SuperLig-One”) has been engineered to accept a Pregnant Leach Solution (“PLS”), with the initial output products being carbonate salts of the critical rare earth elements dysprosium, europium and terbium derived from the Bokan Dotson-Ridge Heavy REE Project in Southeast Alaska. The Plant is a “proof of concept,” precedent to a commercial MRT system, capable of accepting PLS feedstock from multiple and diverse feedstock sources, and is expected to have several advantages over conventional processes for REE separations:
1. Clean Chemistry – The MRT system is based on green chemistry principles throughout. Minimal waste is generated. No organic solvents are used. Few chemicals are used and those used in washing and elution of columns are as benign as possible. Energy requirements are minimal.
2. High Selectivity – the high selectivity of the SuperLig® products makes possible separation and recovery of REE from the PLS at >99% purity level, and subsequent separation of individual REE at >99% levels. Results of these high recovery levels are achievement of maximum economic value, minimal loss of REE to the tailings, many fewer stages required to achieve given REE purities, and reduced use of auxiliary substances.
3. Reduced Capex – the entire MRT operation is physically and operationally simple reducing capital costs.
4. Reduced Opex – the MRT operation requires fewer personnel, equipment, and chemicals thereby reducing operating costs.
5. Operating Standards – the green chemistry MRT operation should readily meet stringent environmental standards in the U.S.
6. Targeted High-Value Separations – Dy can be separated in a targeted manner from the REE without the need to first separate low-value rare earths, such as Ce and La.
Based on the bench-scale results reported earlier (see Ucore Press Releases dated March 2, 2015 and April 28, 2015) and the anticipated results from the Plant, all scale-up parameters for future commercial plants are expected to be established. Commercial plants are under initial conceptualization by Ucore and IBC, based on separation of targeted REE that will be of maximum value to end-use products (see block diagram below):
The separation of selected individual REE using MRT provides a platform for maximum value-added in end-use markets. High selectivity, coupled with the elimination of organic solvents, results in a clean, efficient separations process that can be applied to numerous feed sources and can produce purified REE for introduction directly into the manufacturing chain of a variety of end-use products.
Problems associated with the use of organic solvents in chemical production processes have been well documented. A major reason for the problems associated with the use of solvent extraction (“SX”) in REE processing is the low selectivity and slow reaction kinetics of SX for target REE either in separating these metals from gangue metals or from each other. These deficiencies result in low recovery rates, many separation stages, extended time periods for effective separations, and the inability to separate individual REE in a targeted manner – resulting in the requirement to first separate low-value rare earths, such as Ce and La. The results are increased capital and operating costs, including low recovery rates and extended processing times that result in high working capital requirements due to ‘in-process’ REE inventories. MRT, by contrast, has high selectivity, high recovery rates, and rapid processing times for REE separations both from gangue and from each other.
For further information, please see the long form White Paper on the application of MRT to REE separations, available at the following link: WhitePaper_REE_Separations.pdf
MRT Pilot Plant Facility, Salt Lake City, Utah
Conceptual Artist Rendering