ABSTRACT
In this study, the removal of cadmium and copper ions from aqueous solutions was investigated by waste activated sludge (WAS) under three conditions: (1) without any aeration and feeding, (2) by aeration without feeding and (3) by simultaneous aeration and feeding. The initial concentration, temperature, contact time, aeration and feeding had influence in Cd2+ and Cu2+ removal. The maximum removal of Cd2+ and Cu2+ was obtained with an initial concentration of 5 mg/L of each heavy metal that occurred in the third step (aeration and feeding of activated sludge) with removal efficiency of 75.45% and 76.91% for Cd2+ and Cu2+, respectively. This study showed that WAS has a high biosorption removal capacity for Cd2+ and Cu2+ and can be used as an effective biosorbent for the removal of cadmium and copper and/or other types of heavy metals from industrial wastewaters.
Acknowledgments
The authors are most grateful to the laboratory staff of the Department of Environmental Health Engineering School of Public Health, Tehran University of Medical Sciences, Tehran, Iran, for their collaboration in this research.
Disclosure Statement
No potential conflict of interest was reported by the authors.