Remediation strategies for heavy metals contaminated ecosystem: A review

Industries and anthropogenic activities around us engender our natural resources with their noxious discharge, untreated waste water or sludge containing variety of heavy metals. These toxic metals in turn are emerging health risks for living beings triggering allergies, infection, defects and diseases. Consequently, there is evolving needs for ecologically safe, systematic and novel approach to remediate these toxic heavy metals. Physical, chemical and biological methods have not been much effective in dealing of contaminated ecosystem. These conventional approaches have limitation in terms of higher cost, energy consumption and less efficiency. Overcoming their drawbacks, adsorption, a physico-chemical surface phenomenon came to light which is a way cheaper, effective, flexible, reactive and efficient technique for eliminating heavy metals like cobalt, chromium, lead, nickel, mercury, arsenic, uranium, cadmium, copper etc. Modulating chemical and physical characteristics of microbes, lignocellulosic material, industrial waste biomass, nanotubes, metal organic frameworks (MOFs) and nanocomposite material, escorts in fabricating a magnificent adsorbent. This review critically evaluates various type of adsorbents, their application and adsorption efficiency. It also analysed the parameters affecting the adsorption processes.