Latest insights on technologies for halides and halogenated compounds extraction/abatement from water and wastewater: Challenges and future perspectives

Halides and halogenated compounds are among the important water pollutants that are detrimental not only to the well-being of industrial facilities but also to aquatic life and the health of mankind when their presence exceeds tolerable limits. They are naturally present in brackish waters; introduced into the environment via anthropogenic activities. Water disinfection via halogenation can also cause their presence in the water. Decontamination of industrial wastewater (of halides and halogenated compounds) is required to ensure its suitability for reuse or safe discharge into the environment. The importance of treating halide or halogenated compounds-laden water meant for human consumption cannot also be overemphasized. As part of efforts to conserve water resources and ensure their safety for consumption, scientific research has discovered methods of treating halide and halogenated compounds-laden waters, and these methods are proving to be effective. Here, we review the mechanisms, the most recent findings, and the progress of the highly effective and widely accepted techniques (such as green solvent extraction, reverse osmosis, nanofiltration, electrodialysis, ion-exchange, and adsorption). There are strengths and weaknesses of these technologies which are well explored in this article. Furthermore, future research directions, which serve as a foundation for further improvements to these methods, are not overlooked.