(383z) Multi-Scale Modeling and Optimization of Membranes to Enable Process Intensification of Critical Mineral and Material Recovery

The term “critical minerals and materials” (CMMs) refers to the 68 minerals and materials identified by the US Department of Energy as having high-risk supply chains [1]. Securing the supply chains of these CMMs is essential to national security [1]. While CMMs can be harvested from primary (e.g., mineral ores) or secondary (e.g., industrial waste) sources [2], this work focuses on the recovery of CMMs from the leachate of spent lithium-ion batteries. Specifically, we utilize a membrane-based process called diafiltration to separate metals, such as lithium and cobalt, within the leachate. Membrane systems exhibit great potential for CMM recovery due to their energy and space efficiency, as well as their relatively low cost [2,3].

Modeling the diafiltration of CMMs is non-trivial because realistic CMM feed streams contain multiple components with varying concentrations [2]. Thus, a high-fidelity model that can capture the relevant transport phenomena is a system of partial differential algebraic equations. Additionally, we must bridge the gap between the molecular and bench scales at which membrane materials are typically characterized and the process and infrastructure scales at which we aim to implement the membrane systems.

In this work, we present a high-fidelity membrane model for the diafiltration of a multiple-component CMM stream that can help connect material property targets (i.e., solute rejection or sieving coefficients) and process-level performance metrics (i.e., overall solute recovery). Further, we can investigate staged diafiltration cascades to understand how the multi-component nature of CMM streams impacts process design.

Research Interests:

Molly Dougher is a fourth-year PhD Student at the University of Notre Dame, advised by Alexander Dowling. Funded by the multi-institutional, collaborative project, Process Optimization and Modeling for Minerals Sustainability (PrOMMiS), her research primarily focuses on modeling and optimizing membrane systems to facilitate the design and scale-up of separations for critical mineral and material recovery. Her research interests focus on the mathematical modeling and optimization of chemical engineering processes. Molly is seeking full-time positions starting as early as spring 2027.

References:

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

[2] 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.

[3] 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.