Keywords: sewage sludge, heavy metal ions, adsorption isotherms, desorption, heavy metals, copper ions, lead ions, aqueous solutions, dilute hydrochloric acid
Removal of copper and lead ions from aqueous solutions by adsorbent derived from sewage sludge
Adsorbent prepared from sewage sludge has been used for the adsorption of Cu
2+and Pb2+ from aqueous solutions. It was noted that an increase in removal efficiency achieved 72% and 56% when agitation time achieved 120 min, and a decrease in the removal efficiency from 81% and 70% to 36% and 40% when the heavy metals initial concentration from 10 mg L
?1to 80 mg L
?1for Cu2+ and Pb2+ concentration, the removal efficiency increased with the adsorbent concentration increased. The Langmuir model fitted the experimental data reasonably well. The adsorption capacities achieved 9.737 mg g
?1and 7.386 mg g
?1for the Cu2+ and Pb2+, respectively. Desorption studies were performed by using dilute hydrochloric acid. Quantitative recovery of the metal ion is possible. The mechanism of adsorption seems to be ion exchange.