Abstract
High-salinity mine water generated during membrane concentration of mine water contains structurally stable complex organic matter that resists removal and mineralization by conventional advanced oxidation processes, ultimately producing low-value by-product salts that hinder the resource utilization pathway. Leveraging the ultraviolet sensitivity of inherent chromophore groups and conjugated structures, this study developed an ultraviolet-activated assisted electrochemical process. By harnessing ultraviolet/oxidant synergies, this approach achieves ~89.9% total organic carbon removal, with minimal performance decay over 1000 hours. Combined with ultraviolet-visible spectroscopy, fluorescence excitation-emission-matrix spectroscopy, fourier transform ion cyclotron resonance mass spectrometer, and model contaminant experiments, this study elucidates an ultraviolet activation and radical attack synergistic mechanism driving organic mineralization. The direct integration of purified brine with bipolar membrane electrodialysis successfully produces acid, high-purity alkali (>99%), and reusable water, thereby closing the loop of impurities removal and resource recovery. This integrated system offers a strong strategy for high-value resource recovery and sustainable mine water management.
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All the data supporting the findings of this study are available within the Article and its Supplementary Information files. Source experimental data are available via figshare (https://doi.org/10.6084/m9.figshare.31220905)59. All the raw data relevant to the study are available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgments
We gratefully acknowledge the financial support from the Major Program of the Ministry of Science and Technology (MOST) of China (no. 2023YFC 3210300).
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X.L. and G.Z. conceived the idea. X.L. performed the experimental studies. X.W. provided the actual high-salinity mine water samples. X.L., Y.C., Y.G., Y.L., Q.W., G.Z., H.L., and J.Q. carried out the analysis. X.L. and G.Z. wrote the manuscript. All authors contributed to its preparation and approved the final version.
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Liu, X., Chai, Y., Gu, Y. et al. UV-activated assisted electrochemical process for mine water deep mineralization and resource recovery. Nat Commun (2026). https://doi.org/10.1038/s41467-026-70043-9
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DOI: https://doi.org/10.1038/s41467-026-70043-9
