Chemically modified low cost treatment for heavy metal effluent management

The removal efficiency of lead [Pb(II)], zinc [Zn(II)], nickel [Ni(II)] and chromium [Cr(VI)] from aqueous solutions by adsorption on non‐conventional materials (rice husk and sawdust) in its natural form and on their chemically modified form is presented. It is found that adsorption potential varies as a function of contact time, concentration, particle size, pH and flow rate. Of all the low cost adsorbents used in this study, sawdust is found to possess greater adsorption efficiency for all metals than rice husk under identical experimental conditions. Chemically activated sawdust could remove 95 percent of Pb(II), 93 percent of Zn(II), 80 percent of Ni(II) and 75 percent of Cr(VI) from the metal bearing industrial effluents.