A critical review on classifications, characteristics, and applications of electrically conductive membranes for toxic pollutant removal from water: Comparison between composite and inorganic electrically conductive membranes

• Published in: Journal of hazardous materials 2022-08, Vol.436, p.129162-129162, Article 129162
• Main Authors: Mo, Yinghui, Zhang, Lu, Zhao, Xin, Li, Jianxin, Wang, Liang
• Format: Article
• Language: English
• Subjects: Electrically conductive membrane; Electrophysical/electrochemical removal mechanisms; Fabrication; Heavy metal ions; Pore size and conductivity; Recalcitrant organic pollutants
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2022.129162

Research efforts have recently been directed at developing electrically conductive membranes (EMs) for pressure-driven membrane separation processes to remove effectively the highly toxic pollutants from water. EMs serve as both the filter and the electrode during filtration. With the assistance of a power supply, EMs can considerably improve the toxic pollutant removal efficiency and even realize chemical degradation to reduce their toxicity. Organic–inorganic composite EMs and inorganic EMs show remarkable differences in characteristics, removal mechanisms, and application situations. Understanding their differences is highly important to guide the future design of EMs for specific pollutant removal from water. However, reviews concerning the differences between composite and inorganic EMs are still lacking. In this review, we summarize the classifications, fabrication techniques, and characteristics of composite and inorganic EMs. We also elaborate on the removal mechanisms and performances of EMs toward recalcitrant organic pollutants and toxic inorganic ions in water. The comparison between composite and inorganic EMs is emphasized particularly in terms of the membrane characteristics (pore size, permeability, and electrical conductivity), application situations, and underlying removal mechanisms. Finally, the energy consumption and durability of EMs are evaluated, and future perspectives are presented. [Display omitted] •Composite EMs generally belong to MF/UF and inorganic EMs generally belong to MF.•Conductivities of carbon-based composite/inorganic EMs and TinO2n-1 EMs are close.•Inorganic EMs are more investigated for AO-coupled filtration than composite EMs.•Composite EMs used for electrochemical oxidation are basically based on PTFE.•EMs effectively remove small recalcitrant organic pollutants and heavy metal ions.