Investigations on the separation of metal-bearing values from secondary sources in the production of value-added products

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The Canadian mining industry contributed $97 billion to the nation's Gross Domestic Product in 2018 (Mining.ca-2019). Mineral exports valued at $105 billion in 2018 accounted for 19% of Canada's domestic exports. Canada ranks among the top five countries in the global production of 15 minerals and metals. It is third in graphite, indium and platinum group metals. One application area for graphite (C) as it relates to the current proposal is in the production of anode material in the electric-car batteries, which also use a significant amount of nickel-cobalt for cathode composition (at much higher grades than the Ni grades in ores). According to recent production statistics, however, Ni-Co production declined in Canada. In 2018, Canada lost the top-five ranking position for Ni-Co. The elements C, Ni and Co focused on as part of the current proposal are in the list of strategic materials critical to the economy of Canada. In 2019, the Canadian government announced a plan to develop a strategy to rebuild the domestic supply of such critical elements. In parallel with the increased use of mineral and metal products for various applications, the need for their recovery from secondary sources has increasingly become important. Recycling is a crucial part of sustainability in mining/metallurgical industries, where environmental quality is very important. Traditionally, tailing areas of numerous mining sites constitute the main secondary sources of recoverable minerals due to process losses. There is a tremendous potential for recoverable Ni-Co bearing minerals in tailing areas, amounting to an economic value exceeding $10 billion, which can help restore Canada's rank among the top five countries. The long-term objective of the proposed research program is to significantly contribute to the security of future domestic supply of Ni-Co through the development of novel processes for their recovery from secondary sources, namely, storage areas of tails and spent lithium-ion batteries. The short-term objective is to develop separation methods involving the use of the equipment and new reagent systems in these two areas. Two of the four subprojects planned will focus on a novel use of hydrocyclone mechanism for the separation of graphite from Ni-Co bearing particles in spent batteries and from scavenger tails. The other subprojects will focus on fundamental surface chemical investigations and their applications involving novel flocculation, magnetic and selective flotation separation techniques described in this proposal. The results and conclusions obtained will be a basis for pilot and plant investigations as well as the development of new flowsheets originating from this research. The proposed program will provide training for a total of 9 highly qualified personnel, with 2 Ph.D. students, 2 MASc, and 5 undergraduate students for experimental strategies, data analysis and modelling skills to make needed contributions to the Canadian mining industry.