Following the initial development of IMC’s RapidSX™ process for the separation of rare-earth elements (REEs), the company turned its attention to the separation of nickel (Ni) and cobalt (Co) from a pregnant leach solution (PLS) produced from a ‘real-world’ bulk sample of Ni-laterite ore.
The testing was completed first at the bench scale, and then at the pilot-scale, at IMC’s facilities hosted by Process Research Ortech Inc. (PRO) in Mississauga, Ontario, capable of producing up to 2 tonnes of metals / month.
In addition to utilizing the company’s patent-pending RapidSX process for the separation and purification of Ni and Co from concentrates, the company has also developed a proprietary chloride-based leaching process for producing the PLS, with a cost-saving acid-regeneration step. This allows IMC to extract and to monetize over 80% of the metals present in these ores, while reducing acid consumption and cost. Commercial-grade (99.6%+) purities For Ni, Co and other metals were obtained.
Ni is of vital importance in the manufacturing of stainless steel, other steel, non-ferrous and super alloys, as well as plating, metal-hydride rechargeable batteries and catalysts. Co is essential for the production of Li-ion rechargeable batteries, super alloys, cutting tools, high-performance magnets, catalysts and other applications. Almost all Co, however, is produced as a by-product of copper (Cu) and Ni mining, and sustainable sources can only be achieved through low-cost extraction methods.
The RapidSX process is suitable for concentrates produced from Ni-sulfide ores. However, existing Ni-sulfide deposits are being depleted through mining, with few high-quality exploration targets on the horizon. Ni-laterite deposits are projected to become the most important source of Ni in the future. In addition, future demand for Co in Li-ion batteries is projected to grow dramatically, as electric vehicles take increasing market share in the automotive sector.
This combination of factors, makes it important that the industry has access to efficient processes for producing Ni and Co from lateritic ores, that are cost effective even at today’s relatively low prices for these metals.
The RapidSX approach reduces the number of solvent-extraction (SX) steps required for Ni and Co separation, by over 50% when compared to conventional SX, leading to a significant reduction in plant footprint and associated capital expenditures. The process also leads to reductions in operating costs and time to process completion.
IMC’s overall process approach for Ni and Co includes the electrowinning of the metals produced via the RapidSX process. The multi-stage approach also produces a number of other, valuable commercial-grade metallic compounds, of significant interest to the specialty-chemicals industry.
Following the initial success of the scaled RapidSX-based system, in parallel to its work on REEs, IMC is now in the process of completing its Ni-Co separation pilot-scale work, and developing plans for a commercial-scale demonstration facility, for the cost-effective production of a Ni, Co and other metals, via the RapidSX process.
Based in North America and capable of producing up to 1,000 tonnes / year of Ni and 150 tonnes / year of Co, IMC estimates that this facility would cost in the region of $8-9M to build – a fraction of the cost that a conventional leaching / solvent extraction / electrowinning (L/SX/EW) facility would require. Ni, Co and other metals would be produced in the demonstration facility from purchased lateritic ores and concentrates.
The company is working with current and future producers of Ni and Co on the development of the RapidSX program, and seeks additional strategic and financial partners to help make the Ni-Co demonstration facility a reality.
Given the anticipated reduced plant footprint and low capital costs, IMC is interested in the potential for placing RapidSX-based separation facilities on the same site as upstream hydrometallurgical plants, with or without IMC’s chloride leaching and acid regeneration module. This will allow Ni-Co producers to cost effectively integrate the processes for the production and separation of Ni-Co concentrates, improving the overall margins associated with the production of these metals.