Ocean-based sorbents for decontamination of metal-bearing wastewaters

Remediation of heavy metal contaminated aqueous streams is of utmost importance due to the recalcitrant and persistent behavior of heavy metals in the environment. Traditional removal techniques used for the remediation of toxic heavy metals are either costly or inefficient as well as produce enormous quantity of toxic chemical sludge. On the other hand, biosorption is evolving as an alternative treatment method to the traditional methods for remediation as well as selective recovery of metal ions from contaminated waters. Biosorption presents several inherent merits over other conventional as well as biological methods such as cost-effectiveness, high sorption uptake, biological or chemical sludge minimization, regeneration/reuse of biosorbents, operation over wide range of physicochemical conditions as well as a possibility of metal recovery. Of the various biosorbents, ocean-based sorbent materials are copious and economical biosorbents for metal-bearing wastewaters. Seaweeds, crab shell, seagrass, seashell and fish scales are studied as ocean-based sorbents for various metal ions.