Fluoride removal from water by adsorption—A review

Fluoride contamination in drinking water due to natural and anthropogenic activities has been recognized as one of the major problems worldwide imposing a serious threat to human health. Among several treatment technologies applied for fluoride removal, adsorption process has been explored widely and offers satisfactory results especially with mineral-based and/or surface modified adsorbents. In this review, an extensive list of various adsorbents from literature has been compiled and their adsorption capacities under various conditions (pH, initial fluoride concentration, temperature, contact time, adsorbent surface charge, etc.) for fluoride removal as available in the literature are presented along with highlighting and discussing the key advancement on the preparation of novel adsorbents tested so far for fluoride removal. It is evident from the literature survey that various adsorbents have shown good potential for the removal of fluoride. However, still there is a need to find out the practical utility of such developed adsorbents on a commercial scale, leading to the improvement of pollution control.

► Fluoride removal from water using ‘adsorption’ process has been reviewed.
► A list of ∼ 100 adsorbents has been presented along with their adsorption capacities.
► The influence of various parameters on fluoride removal has also been presented.
► Recently developed novel adsorbents for defluoridation have been discussed.