Removal of heavy metals from waste water using different biosorbents

The discharge of waste water containing heavy metals like Cr, Cd, Cu from tanneries, electroplating units, metal processing industry etc is the major cause for metal pollution which in turn causes adverse effects in the environment. The conventional methods available for removal of heavy metal are costly and also produce some toxic sludge. This has lead to the invention of new technology like biological removal of heavy metal. In this paper use of various biosorbents like plants, microbes and their derived products were reviewed with context to metal removal. Various modes of operation and reactor types, adsorption kinetics with respect to growth condition and metal sorption were also given importance.