REMOVAL OF HEAVY METALS FROM ELECTROPLATING WASTEWATER BY FERRITISATION

A laboratory scale reactor was designed for the purification of synthetic heavy metals containing wastewater and electroplating wastewater. The optimum conditions for ferritisation of heavy metal cations were studied with respect to the ratio of M²⁺ to Fe²⁺, the O₂ flow rate, pH and temperature. The recommended ratio of Cu²⁺ to Fe²⁺, Ni²⁺ to Fe²⁺, and Zn²⁺ to Fe²⁺ were 1 to 2, 1 to 5 and 1 to 10, respectively, The optimum concentration of Fe²⁺ added to synthetic wastewater containing Cu-Ni, Cu-Zn, Ni-Zn and Cu-Ni-Zn were 800, 1,400, 1,600 and 1,400 mg 1^-1, respectively. The Fe²⁺ concentration used to treat wastewater containing two and three metal cations was 100-200 mg 1^-1higher than the Fe²⁺concentration used to treat wastewater containing a single metal cation. The optimum O₂ flow rate, pH and temperature were 100 ml min^-1, 10 and 50 C, respectively. Heavy metals in synthetic wastewater were remover > 99.5 %. 99.80% of nickel, 99.9% of zinc and 99.92% of iron were removed from electroplating wastewater. 

Keywords: ferrite sludge, wastewater purification, hazardous materials, precipitation, decontamination, recycling

Corresponding author: E-mail:  kcchompo@kmitl.ac.th