Interplay of backbone rigidity and water content on ion/ion selectivity in hydrated polymer membranes

ORAL

Abstract

Increasing lithium demand requires new and improved methods for purification. Membrane-based separation processes, such as selective electrodialysis, hold promise for efficiently separating lithium from other contaminants, such as magnesium. Successful implementation of these technologies requires materials with high selectivity of lithium over other ions while maintaining high lithium conductivity. Two factors that are known to play important roles in governing membrane performance are equilibrium water content and polymer segmental dynamics. We perform coarse-grained molecular dynamics simulations to examine the interplay between these two factors and the impact on ion/ion selectivity. These simulations rationalize our observed experimental selectivity trends for cellulose acetate membranes and provide guidance for future investigation into improved membrane design.

* This work was supported as part of the Center for Materials for Water and Energy Systems (M-WET), an Energy Frontier Research Center funded by the U.S. DOE under Award #DE-SC0019272. The authors acknowledge the Texas Advanced Computing Center (TACC) for the generous allocation of computing resources.

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Presenters

  • Paul R Irving

    The University of Texas at Austin, University of Texas at Austin

Authors

  • Paul R Irving

    The University of Texas at Austin, University of Texas at Austin

  • Harnoor S Sachar

    The University of Texas at Austin, University of Texas at Austin

  • Nico Marioni

    The University of Texas at Austin, University of Texas at Austin

  • Everett S Zofchak

    The University of Texas at Austin, University of Texas at Austin

  • Zidan Zhang

    The University of Texas at Austin, University of Texas at Austin

  • Benny D Freeman

    University of Texas at Austin, The University of Texas at Austin

  • Venkatraghavan Ganesan

    University of Texas at Austin, The University of Texas at Austin