A Self-Regenerable Fiber Sloughing Its Heavy Metal Skin for Ultrahigh Separation Capability

Abstract

Developing efficient separation materials for recovering metal resources from aqueous environments is crucial for the sustainable water-food-energy nexus, which addresses the interdependence between energy production, water production, and energy consumption. Various material-based separation processes have demonstrated outstanding performance. However, electric energy and chemicals are used to frequently replace the separation materials used in such processes owing to their short life span. This study presents a methodology for designing the self-regenerable fiber (SRF) according to the types of metals through a self-regeneration model. The SRF can semi-permanently recover the metal resources from water through a repetitive adsorption-crystallization-detachment process of metal ions on its surface. The ionic metal resources are adsorbed and crystallized with the counter-anions on the SRF surface. Next, the metal crystals are self-detached from the SRF surface by the collision between the crystals and curvature and non-sticky surface of the SRF. Thus, a module containing the SRF maintains its metal recovery capability even during continuous injection of the metal solution without its replacement. These findings highlight the significance of interfacial engineering and further guide the rational design of energy/environmentally friendly resource recovery modules.