Heavy metals removal in industrial effluents by sequential adsorbent treatment

摘要

A method for metal removal can be applied to industrial wastes without prior treatment using solid adsorbents such as sand, silica, coal and alumina. This study was conducted to evaluate the removal of heavy metals in an aquatic system without prior treatment. An important aspect of the proposed method was that the removal was performed on several metals at a pH range in which a given metal undergoes an adsorption process, making the method useful for wastewater treatment. Lead was the metal of most interest due to its occurrence in waste from storage-battery manufacture. After the adsorption process, the Pb concentration, as well as that of Cd, Ni, Cr and Cu, were below the detection limit. For other metals, removal was observed to be approximately 20-30 for Ca, Mg and Mn and above 80 for Cr, Pb, Ni, Cd and Cu, using alumina as an absorbent.