Recent advances in adsorption techniques for fluoride removal – An overview

One of the biggest issues throughout the globe is the increasing fluoride pollution of the aquatic environment as a result of both naturally occurring and anthropogenic activities. Its existence is necessary around lower levels, but when consumed in amounts exceeding 1.5 mg/L in mostly impacted drinking water, it proves harmful to human beings owing to biogeochemical processes together with geologic or anthropomorphic reasons. The prolonged exposure to naturally occurring high levels of fluoride in groundwater can have the adverse health effects on a significant population worldwide. It is crucial for finding efficient and reliable solutions to remove excessive fluoride within aquatic environments. Among the frequently employed methods for eliminating fluoride, the adsorption approach has been extensively investigated and presents a remarkably effective, uncomplicated and economical procedure for reducing fluoride levels from water within the permissible level of 1.5 mg/L in primarily polluted drinking water as a result of geochemical reactions and geological or human-caused influences. This review highlights the latest and current advancements in the removal of fluoride from water environments using adsorption techniques. A comprehensive review is presented by focusing on the removal of fluoride from aqueous solutions using numerous adsorbents and their defluoridation capabilities under various parameters (initial fluoride concentration, pH, temperature, time etc.). It is clear from the literature that a variety of adsorbents exhibiting significant fluoride removal capacities were successfully created, but there remains a pressing need to scale up the removal techniques for industrial applications. Additional research on regeneration in real-world settings is imperative to reclaim the adsorbent material, thereby improving the economic potentiality of technique.