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Waste streams often contain valuable resources such as metallic species that are not recovered but simply lost instead. The selective recovery of valuable species such as precious metals from industrial aqueous streams, or indeed any aqueous stream, can be economically viable and environmentally attractive, and significantly improve the sustainability of manufacturing or mining processes. It lowers the chemical and energy demand of raw materials and reduces the concentration of harmful metals being discharged into the environment.

Prof. Hankins

However, selectively recovering a certain metallic species from challenging waste streams containing a vast array of other pollutants, such as other metals and organics, is a challenging task. Novel processes and materials are being developed to achieve this task and offer a circular, sustainable and economically appealing approach to valuable metal recovery from aqueous industrial effluents.


Ming Chen, N. P. Hankins: “Interaction Among Branched Polyethylenimine (PEI), Sodium Dodecyl Sulfate (SDS) and Metal Cations During Copper Recovery from Water using Polymer-Surfactant Aggregates”, Journal of Water Process Engineering, 2020, 34, 101170. doi:10.1016/j.jwpe.2020.101170.

Licheng Shen and Nicholas Hankins: “Removal of Metallic Ions at the Parts per Billion Level from Aqueous Solutions Using the Polymer-Surfactant Aggregate Process”, Journal of Water Process Engineering, 2019, 30, 100486.

L.C. Shen, and N.P. Hankins: “Metallic Anion Removal from Dilute Aqueous Solutions Using Polymer-Surfactant Aggregate Process: Effect of Surfactant Chain Length”, Journal of Water Process Engineering, 2017, 20, 243-248.

H. Wu, L. C. Shen, H. Y. Hu, N. P. Hankins, and W. E. Huang: An Efficient Microalgal Biomass Harvesting Method with a High Concentration Ratio Using the Polymer-Surfactant Aggregates Process, Algal Research, 2017, 30, 86-93.

L.C. Shen, A. Lo, X.T. Nguyen, and N.P. Hankins: “Recovery of Heavy Metal Ions and Recycle of Removal Agent in the Polymer–Surfactant Aggregate Process”, Separation and Purification Technology, 2016, 159, 169–176.