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Design principles of catalytic reactive membranes for water treatment

Nature Water volume 3, pages 949–962 (2025)Cite this article

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Abstract

Reactive nanofiltration membranes integrate catalytic transformation with molecular separation to remove diverse aqueous contaminants. However, their development is hindered by an incomplete understanding of the interplay between solute mass transport and chemical reactions. Here we introduce key design principles by systematically evaluating their performance using a modelling approach. Efficient oxidant transport is essential for maximizing contaminant degradation. For membranes with surface-loaded catalysts, avoiding mass transport limitations ensures effective catalyst utilization, whereas for membranes with interior-loaded catalysts, optimizing oxidant partitioning enhances oxidant utilization efficiency. In addition, selective solute rejection reduces interference from natural organic matter, facilitating more selective contaminant transformation inside membrane pores. Consequently, contaminant transformation is dominated by surface-catalysed reactions at low permeate water fluxes, while interior-catalysed reactions dominate at high fluxes. However, rejecting both oxidants and contaminants does not enhance surface-catalysed treatment performance under an optimally designed scenario, highlighting the need for strategic design of membrane rejection. Beyond organic contaminant removal, nanofiltration membranes also minimize secondary contamination by rejecting the produced salts during the catalytic reactions. Furthermore, strategic selection of oxidant–catalyst pairs can enhance treatment performance by generating suitable reactive species. By establishing a theoretical framework for designing and optimizing reactive nanofiltration membranes, this study provides critical insights into the development of advanced water treatment technologies.

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Fig. 1: NF-based reactive membranes and their perceived benefits.
Fig. 2: Performance of reactive membranes with catalysts loaded on the membrane surface.
Fig. 3: Performance of reactive membranes with catalysts loaded inside the active layer.
Fig. 4: Reactive membranes with catalysts distributed on both the surface and inside the membrane active layer.
Fig. 5: Selection of oxidants and catalysts for efficient contaminant transformation.

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Data availability

The source data for the figures are provided in Excel format (.xlsx) and are publicly available via Figshare at https://doi.org/10.6084/m9.figshare.29333090 (ref. 79).

Code availability

The code for the model described in the paper is available publicly via GitHub at https://github.com/yanghuaduan/Reactive_NF_membrane.

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Acknowledgements

This research was partially funded by the Yale University Superfund Research Program (SRP), which is supported by a grant from the National Institute of Environmental Health Sciences, National Institutes of Health (award no. P42ES033815) and the Rice Center for Membrane Excellence (RiCeME). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

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Authors and Affiliations

  1. Department of Civil and Environmental Engineering, Rice University, Houston, TX, USA

    Yanghua Duan, Ruoyu Wang & Menachem Elimelech

  2. Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA

    Amit N. Shocron

  3. Rice Center for Membrane Excellence, Rice University, Houston, TX, USA

    Menachem Elimelech

  4. Rice WaTER Institute, Rice University, Houston, TX, USA

    Menachem Elimelech

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  1. Yanghua Duan
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  2. Ruoyu Wang
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Contributions

Conceptualization: Y.D. and M.E. Methodology: Y.D., R.W., A.N.S. and M.E. Formal analysis: Y.D., R.W., A.N.S. and M.E. Writing—original draft preparation: Y.D. Writing—review and editing: Y.D., R.W., A.N.S. and M.E. Supervision: M.E. Funding acquisition: M.E. All authors have read and agreed to the published version of the study.

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Correspondence to Menachem Elimelech.

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Duan, Y., Wang, R., Shocron, A.N. et al. Design principles of catalytic reactive membranes for water treatment. Nat Water 3, 949–962 (2025). https://doi.org/10.1038/s44221-025-00467-y

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