AKF? KERATIN-PROTEIN FIBER AS A BIOSORBENT FOR HEAVY METALS FROM SOLUTIONS

摘要

Avian keratin-protein fiber (AKF?) has a strong affinity for biosorption of heavy metals from solutions. Laboratory tests indicate that keratin-protein fiber can effectively remove dissolved species of Pb,Cu,Cd,and Zn from solutions. In addition,chloro-complexes of precious metals can be selectively removed at an acidic pH of 1-2. Keratin-protein fibers can be used several times by conducting loading/elution cycles. As an example,more than 90% of absorbed copper can be removed by elution with hydrochloric acid at a pH of 1.5. Sorption kinetics of most of the metals is very rapid. The mechanism of absorption is complex. It is believed that both the ion exchange mechanism and selective adsorption at the surface binding sites are controlling the metal uptake. Keratin-protein is stable at acidic as well as alkaline pH. It has strong potential to be used in process water treatment for mining and plating applications, and removal of trace metals from drinking water.