Grant: Alliance Grants

Lithium as a critical constituent for the fast-growing green economy (e.g. rechargeable batteries and storage facilities) is extracted largely from either spodumene (LiAlSi2O6) in pegmatites or lithium-bearing brines. Canada is well endowed with spodumene and petalite (LiAlSi4O10) pegmatites from coast to coast to coast but is lagging in bringing these lithium resources to the market due to technical problems in mineral beneficiation. Two of the most serious technical problems hampering Canadian companies in developing lithium pegmatite resources are 1) inconsistent recovery of spodumene and petalite from high-grade ores and 2) ineffective recovery of these minerals from low-grade ores. We hypothesize that the inconsistent and ineffective recovery of spodumene and petalite arises from their diverse surface chemistry, which in turn determines their adsorption behavior during the recovery process by froth flotation. Accordingly, we have assembled a team of mineralogists, structural geologists, synchrotron specialists, and metallurgists with complementary expertise to test this hypothesis. Specifically, we plan to use advanced synchrotron X-ray absorption spectroscopy and X-ray photoelectron spectroscopy to investigate the surface chemistry of spodumene and petalite in selected lithium pegmatites. In particular, we plan to collaborate with our primary industrial partners Rock Tech Lithium Inc. and Pan American Energy Corp. to use their Georgia Lake spodumene and Big Mack petalite pegmatites in northwestern Ontario as examples to document the three-dimensional variations in the surface chemistry of spodumene and pelaite, with an emphasis on those in the most challenging low-grade ores. These results are then used to develop novel flotation processes to effectively recover spodumene and petalite for the sustainable development of Canadian lithium pegmatites. In addition, the surface chemistry data of spodumene and petalite collected with geological contexts are anticipated to provide new insights into the crystallization and deformation histories of pegmatites. Moreover, this research actively engages many Indigenous Nations, including the Métis Nation of Ontario.