Removal ofHeavy Metals From Effluents Using Ion-Exchange Resin

The presence ofheavy metals in the environment is major concern due to their toxicity. Contamination of heavy metals in water supplies has steadily increased over the last years as a result of expansion of industrial activities. Removal of trace amounts of heavy metals can be achieved by means of selective ion-exchange processes. In the present study, the removal of Ni(2+), Fe(3+),and Cr(3+) from industrial effluent was investigated. Experimental investigations were undertaken using the ion-exchange resin Amberlyst 15 wet resin (strongly acidic) and were compared with Activated Carbon.The influence of contact time , metal concentration and amount of resins on the removal process was investigated. For the determination ofthe adsorption behavior of the resin, the adsorption isotherms of metal ions have also been studied. The concentrations of metal ions have been measured by batch techniques. For investigations different amounts of resin were contacted with a fixed volume of Ni(2+), Fe(3+),and Cr(3+) ion containing effluent. The obtained adsorption affinity sequence in the presented work was Ni(2+)>Fe(3+)>Cr(3+). The metal ion concentrations were measured by AAS methods. The uptake of metal ions by the ion-exchange resins was reversible and thus has good potential for the removal of Ni(2+), Fe(3+),and Cr(3+) from the effluent. Selectivity increased in the series: Ni(2+)>Fe(3+)>Cr(3+). Ni(2+) and Fe(3+) shown 100% removal result using 20g of each resins and Cr(3+) shows promising percentage of removal. The results obtained showed that the Amberlyst 15 wet resin and Activated Carbon resin performed well for the removal of the heavy metals. As a low cost adsorbent, activated carbon is more preferable for the removal of heavy metals from the wastewater.