Anwesha Banerjee
McGill University, PhD
EREF Scholar 2024
Life Cycle Perspective on Recycling Lithium-Ion Batteries using Green Chemistry Approaches
Electric vehicles (EV) are currently the most popular choice for consumers all over the globe. But there is an unresolved side to this admirable technological advancement, i.e., its end-of-life (EoL) fate as waste, which if unresolved will contribute to severe negative environmental consequences. EV batteries contain significant amounts of cobalt, lithium, nickel, manganese, aluminum, copper, and graphite. Uneven demand-supply of these metals may impede EV production. Therefore, from a life cycle perspective, only recycling these critical metals can reduce environmental pollution and raw material consumption. The current cost of recycling is too high. The biggest challenge is that they either rely on high temperature pyrometallurgy, whereby the lithium is not recovered, or use hydrometallurgical techniques with strong acid leaching or solvent extraction to recover lithium. Despite their effectiveness, they produce toxic gases, including SOx and NOx, posing a risk to human health and the environment. Over the past few years, innovative recycling methods have emerged to address the high energy consumption and environmental footprint of current battery waste processing technologies described above. Among them, deep-eutectic solvents (DESs), which are both environmentally friendly and cost-effective, will be used in our research for their remarkable selectivity and efficiency in the leaching process. In the proposed research, DES formulations would be developed in a way to enhance the efficacy of suitable hydrogen bond acceptor and donor for dissolution of Li, Mn, Ni, Co from the cathode black mass of lithium-nickel-cobalt-manganese (LNMC) batteries and at room temperature. Subsequently, to recover the essential metals, the research will develop efficient selective separation strategies. This will include designing a novel macromolecule (crown ether)- Fe3O4 nanoparticle composite material to facilitate efficient metal-ion recovery from the solution by magnetic separation. Used DESs will be recovered for future use. Therefore, the focus of the study is a benign Li recovery process from spent LIBs to extract valuable transition metals from cathode black mass and separate Li ions by selective complexation, which enables recycling of the DES back into the extraction process. The overall project therefore follows the green chemistry principles of designing safer solvents, energy-efficient extraction, and reducing derivatives.
Biography
Anwesha Banerjee earned her B.Tech in Civil Engineering from the University of Engineering and Management, India in 2018, followed by an M.Tech in Environmental Engineering from the Indian Institute of Technology Guwahati (IITG) in 2021. Anwesha, under Prof. Ajay Kalamdhad’s mentorship, worked on a solid waste management project at IITG, managing waste for over 8,000 students, 400+ faculty, and 500+ staff. Collaborating with two peers, she focused on waste segregation, collection frequency, and frequent landfill visits. Her master’s research interest was minimizing toxicity by reducing bioavailable fractions of heavy metals and maximizing the efficacy of weed compost application using a 21-day “Rotary drum composter” in the soil and plant systems. She managed to develop a less hazardous chemical transformation generating a product that possesses little or no toxicity to human health and the environment. The findings of which have been published in Environmental Technology & Innovation. Her group also produced “Mati Dhan,” an organic vermicompost now sold on Amazon and other platforms. She is currently pursuing a PhD in Environmental Engineering at McGill University, Canada, and is working under the mentorship of Prof. Subhasis Ghoshal on developing sustainable methods for recovering valuable metals from spent Li-ion batteries from electric vehicles using deep eutectic solvents and nanotechnology. This research is crucial as, by 2030, approximately 11 million metric tonnes of spent LIBs are expected to be generated, and if disposed of in landfills, they could cause serious environmental pollution by allowing toxic heavy metals to penetrate groundwater. Before commencing the Li-ion recycling project, for a brief duration, she also worked on the bioremediation of oil-contaminated sites of the Artic region by studying the growth of Dietzia maris at oil-water interfaces using the delivery of silica nanoparticles with hydroxyapatite (HAP) core-releasing phosphate. The results of this study are published in the Journal of Hazardous Materials. In addition to her academic achievements, she is also an elected representative of the Civil Engineering Graduate Student Society Environment Committee and has been in touch with the McGill-wide Green Lab Initiative for sustainable lab practices. Anwesha is also a student member of the McGill Centre for Innovation in Storage and Conversion of Energy (McISCE), and a research group member at Trottier Institute for Sustainability in Engineering and Design (TISED), McGill University.
