Chemical and Biomolecular Engineering
Faculty Advisor: Alexander Dowling
Winter 2020-21 Project: Novel Diafiltration Cascades for Lithium-Ion Battery Recycling
The importance of lithium-ion batteries is evident from their ubiquity in society and the popularity of electric cars. Worldwide mining of lithium, cobalt, and other raw materials are insufficient to meet projected demand over the next decade, necessitating that better recycling technologies be invented. Traditional energy-intensive processes that recycle spent batteries use large volumes of environmentally harsh solvents and high strength acids in leaching processes to extract metal rich solutions for processing. However, membrane separations are a promising technology that has significant advantages over leaching processes by being more sustainable and energy efficient.
This project is studying how a diafiltration membrane system could be used to separate Lithium and Cobalt in a novel, energy-efficient membrane cascade. This technology could become a disruptive technology for the market and have a significant impact on society with how prevalent lithium ion batteries are. The goal of the project is to reveal that separation processes that were originally thought to be infeasible can be accomplished using existing materials if these problems are attacked using the advanced tools that have been developed in the process systems engineering community. This project uses a novel superstructure model that encodes all possible flow and recycle scenarios at once, allowing the model to explicitly manipulate configuration parameters such as recycle strategies, split fractions, and the sizes of stages. This superstructure thus exploits many degrees of freedom to find novel, optimal configurations for setting up these membrane cascades. These novel configurations allow existing materials to accomplish these tough problems that were thought infeasible before. Additionally, this model can be used to back calculate what a membrane property would have to be to reach a certain recovery of Lithium and Cobalt and thus can provide material property target goals so that membrane technology could replace the ancient leaching processes. This incorporation of data science into the membrane community will allow these new energy-efficient processes to be invented and break into industry.