Heavy metal sequestration from contaminated water: A review

Heavy metal pollution is currently one of the most threatening environmental problems faced by humanity. The removal/treatment of heavy metal ions is of great concern due to their intractableness and accumulative nature. In this article, the technical feasibility of various conventional physico-chemical and bio-sorption methods has been reviewed for the removal of various heavy metal ions from the contaminated wastewater. Keeping environmental sustainability in mind, the particular focus has been laid on biosorption, besides this the advantages and drawbacks of various conventional physico-chemical methods such as chemical precipitation, ion exchange and membrane filtration have also been highlighted in this article. It is evident from the literature survey that the low-cost bio-adsorbents have shown remarkable and outstanding removal capabilities as compared to other physico-chemical methods. In general, the technical feasibility, profitability, cost-effectiveness and efficiency are the key factors in selecting the suitable treatment method for the elimination of heavy metal ions from contaminated water.