"Application of the polyacrylamides on flocculation of metallic cations"
Heavy metals removal; ionic polyacrylamides; ionic flocculation; Analysis of pH; Selectivity (Cu2+/Zn2+).
The wastewater produced by the galvanoplasty industryis a serious environmental problem due to the high concentrations of heavy metals. In this study polymers were used in ionic flocculation to treat synthetic wastewater containing metals, applying four types of polyacrylamides with different ionic loads as agents to remove copper and zinc. Metal removal efficiency was assessed considering the influence of polymer concentration, ionic load and pH. Selectivity (Cu2+/Zn2+) at different polymer concentrations was also evaluated. The results confirm that polyacrylamide is efficient in treating wastewater containing heavy metals. These experiments exhibited removal efficiency of around 40% and pH= 4,5; however, efficiency was more than 80% with pH= 7.0 under the same conditions, when polyacrylamides with average ionicity were used.