Nanoscale control of internal inhomogeneity enhances water transport in desalination membranes

Tyler E Culp; Biswajit Khara; Kaitlyn P Brickey; Michael Geitner; Tawanda J Zimudzi; Jeffrey D Wilbur; Steven D Jons; Abhishek Roy; Mou Paul; Baskar Ganapathysubramanian; Andrew L Zydney; Manish Kumar; Enrique D Gomez

doi:10.1126/science.abb8518

Nanoscale control of internal inhomogeneity enhances water transport in desalination membranes

Science. 2021 Jan 1;371(6524):72-75. doi: 10.1126/science.abb8518.

Authors

Affiliations

¹ Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
² Department of Mechanical Engineering, Iowa State University, Ames, IA 50011, USA.
³ Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, USA.
⁴ DuPont Water Solutions, Edina, MN 55439, USA.
⁵ The Dow Chemical Company, Freeport, TX 77541, USA.
⁶ The Dow Chemical Company, Lake Jackson, TX 77566, USA.
⁷ Department of Civil, Architectural and Environmental Engineering, University of Texas, Austin, TX 78712, USA. manish.kumar@utexas.edu edg12@psu.edu.
⁸ Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA. manish.kumar@utexas.edu edg12@psu.edu.
⁹ Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, USA.

PMID: 33384374
DOI: 10.1126/science.abb8518

Abstract

Biological membranes can achieve remarkably high permeabilities, while maintaining ideal selectivities, by relying on well-defined internal nanoscale structures in the form of membrane proteins. Here, we apply such design strategies to desalination membranes. A series of polyamide desalination membranes-which were synthesized in an industrial-scale manufacturing line and varied in processing conditions but retained similar chemical compositions-show increasing water permeability and active layer thickness with constant sodium chloride selectivity. Transmission electron microscopy measurements enabled us to determine nanoscale three-dimensional polyamide density maps and predict water permeability with zero adjustable parameters. Density fluctuations are detrimental to water transport, which makes systematic control over nanoscale polyamide inhomogeneity a key route to maximizing water permeability without sacrificing salt selectivity in desalination membranes.

Publication types

Research Support, Non-U.S. Gov't