Remediation of toxic fluoride from aqueous media by various techniques

摘要

The demand for pure and clean water increased in the developing states due to their growing population. Hence, the treatment of toxic elements especially fluoride in aqueous solution has emerged a major issue of their public concern. The fluoride pollution in the aqueous system is due to natural and anthropogenic activities which cause several diseases, i.e. Arthritis, cancer, brittle bones, brain damage. The present review article highlights different types of removal techniques including Adsorption, Ion exchange, Membrane filtration and Electrocoagulation used for the elimination of fluoride from aqueous media. The maximum removal capacity of fluoride by fly ash adsorbent was obtained up to 332.5 mg/g. However, the removal efficiency using other technologies such as ion exchange, membrane filtration and electrocoagulation was achieved up to 90?95%, 99% and 85.5%. Among them, adsorption has been explored widely as a very effective and efficient method due to its easy operation, low cost and give satisfactory results. In this perspective, various adsorbents are discussed in this review, i.e. activated carbon, activated alumina, bio-sorbents, natural-based sorbents, agricultural waste sorbents, nano-sorbents and industrial waste sorbents but still there is need to develop such type of materials on a marketable scale for the control of pollution. It is evident from the literature review that every technique showed novel potential for the remediation of toxic fluoride ion.