(138d) Process Systems Engineering-Informed Design and Scale-up of Multi-Stage Diafiltration Cascades for Lithium and Cobalt Recovery from Spent Lithium-Ion Batteries

The U.S. Department of Energy defines critical materials as the 50 “critical minerals” determined by the U.S. Geological Survey [1] and 18 “critical materials for energy.” [2] Including lithium and cobalt, this list denotes materials with high-risk supply chains essential to energy technologies. [2] Typically, harvesting critical materials from primary or recycled sources uses environmentally-taxing techniques, such as acid leaching, solvent extraction, and precipitation. [3] Therefore, we posit leveraging more sustainable technologies like membranes to recover critical materials. [4] Further, as the quality of mineral ore continues to fall close to or below the quality of specific recycled sources (i.e., electric vehicle battery packs), [3] lithium-ion batteries remain an essential feed source for harvesting critical materials.

This work presents the modeling and optimization of a multi-stage diafiltration cascade to recover lithium and cobalt from spent lithium-ion batteries. Modeled in Pyomo [5] using the IDAES-PSE modeling framework [6], the diafiltration flowsheet includes a membrane cascade to isolate lithium and cobalt product streams. Each stream undergoes precipitation to obtain the solid products, and the waste is recycled back into the cascade. We develop a custom costing model for relevant capital and operating expenses to perform a preliminary economic assessment of the membrane system. Superstructure optimization [7] provides the optimal cascade design (i.e., where to place the feed and collect the products) for particular design constraints (i.e., lithium and cobalt recovery) by minimizing the annualized operating cost.

The optimization model developed in this work enables the efficient evaluation of membrane cascade designs across a wide range of process and product specifications, where the cost model indicates the feasibility of implementing this membrane system by providing a cost that can be compared to the baseline costs of current technology. We can extract design trends based on the recovery specifications and determine which types of membrane cascade designs meet product purity specifications. Further, by leveraging the multi-stage design, we can critically evaluate process design as the separation is scaled up. Evaluating sustainable critical mineral separations across the bench to pilot scales is essential for developing and implementing processes that support a circular economy of critical materials.

Acknowledgements: This effort was funded by the U.S. Department of Energy’s Process Optimization and Modeling for Minerals Sustainability (PrOMMiS) Initiative, supported by the Office of Fossil Energy and Carbon Management’s Office of Resource Sustainability.

Disclaimer: This project was funded by the United States Department of Energy, National Energy Technology Laboratory, in part, through a support contract. Neither the United States Government nor any agency thereof, nor any of their employees, nor the support contractor, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof, or any of their contractors.

References

[1] Jason Burton. U.S. Geological Survey releases 2022 list of critical minerals, 2022. https://www.usgs.gov/news/national-news-release/us-geological-survey-re…

[2] What are critical materials and critical minerals? https://www.energy.gov/cmm/what-are-critical-materials-and-critical-min…

[3] Laurianne Lair, Jonathan Aubuchon Ouimet, Molly Dougher, Bryan W Boudouris, Alexander W Dowling, and William A Phillip. Critical mineral separations: Opportunities for membrane materials and processes to advance sustainable economies and secure supplies. Annual Review of Chemical and Biomolecular Engineering, 15:243–266, 2024.

[4] Molly Dougher, Laurianne Lair, Jonathan Aubuchon Ouimet, William Phillip, Thomas Tarka, and Alexander Dowling. Opportunities for process intensification with membranes to promote circular economy development for critical minerals. Systems and Control Transactions, 3:711–718, 2024.

[5] Michael L Bynum, Gabriel A Hackebeil, William E Hart, Carl D Laird, Bethany L Nicholson, John D Siirola, Jean-Paul Watson, David L Woodruff, et al. Pyomo-optimization modeling in python, volume 67. Springer, 2021.

[6] Andrew Lee, Jaffer H Ghouse, John C Eslick, Carl D Laird, John D Siirola, Miguel A Zamarripa, Dan Gunter, John H Shinn, Alexander W Dowling, Debangsu Bhattacharyya, et al. The IDAES process modeling framework and model library—flexibility for process simulation and optimization. Journal of advanced manufacturing and processing, 3(3):e10095, 2021.

[7] Luca Mencarelli, Qi Chen, Alexandre Pagot, and Ignacio E Grossmann. A review on superstructure optimization approaches in process system engineering. Computers & Chemical Engineering, 136:106808, 2020.