Removal of forever chemicals (PFAS) using novel electrocoagulation approaches integrated with renewable energy sources as a green and cutting-edge technology: mechanisms, key parameters, challenges, and opportunities

Abstract Per- and polyfluoroalkyl substances (PFASs) are recognized as “forever chemicals” highly stable compounds that exhibit remarkable resistance to conventional biological and physicochemical degradation processes, thereby posing a persistent threat to aquatic ecosystems and public health. In recent years, electrocoagulation (EC) has emerged as a promising technology for PFAS removal, leveraging multifaceted mechanisms that include the in-situ formation of metal hydroxide flocs, electroflotation, and electro-oxidation. This narrative review article provides a descriptive synthesis of EC-based approaches for PFAS management, grounded in a narrative review methodology and informed by a critical analysis of 28 peer-reviewed studies published between 2010 and 2025. The review systematically evaluates the critical influence of key operational parameters, including electrode material (iron, aluminum, zinc, and hybrid configurations), current density, pH, electrolyte type, and aeration, on PFAS removal efficiency. It further clarifies that complete degradation and mineralization of PFAS compounds generally require the integration of EC with hybrid advanced oxidation processes (AOPs). The performance of the EC process is also assessed through key metrics such as electrical energy per order (EEO), alongside operational cost drivers, including electrode consumption, sludge generation, and the complexities associated with sludge management. Moreover, the integration of EC with renewable energy sources, solar, wind, and microbial is examined not only in terms of its potential to enhance sustainability but also with explicit consideration of associated practical challenges, such as energy intermittency, the necessity of energy storage systems, and the critical need for precise control of direct current (DC) voltage and current parameters. Finally, this review identifies critical knowledge gaps in PFAS-laden sludge management, electrode passivation, process scalability, and techno-economic feasibility, and proposes a forward-looking research agenda aimed at transforming EC from a laboratory-scale concept into a practical, sustainable, and field-deployable technology, particularly for the treatment of PFAS-contaminated water resources.