Purification Process of Wastewater Containing Low Concentration of Co2+ by Neutralized Ferrite Method

The orthogonal experiments were carried out to study the purification process of wastewater containing low concentration of Co2+ by neutralized ferrite method at the appearance of Cu2+, Zn2+ , Mn2+ or their mixture. The neutralized ferrite process can remove Co2+, Cu2+, Zn2+ and Mn2+ efficiently, while the removal efficiency of Co2+ reduced by the appearance of Cu2+, Zn2+, Mn2+ or their mixture. Under the optimized conditions, the decontamination factors (DF) of Co2+ were all above 1.00×104, and the residual concentration was 0.40-0.50 μg/L. Moreover, the residual concentrations of Cu2+, Zn2+ and Mn2+ were all lower than 5 μg/L. With single ion, the DF sequence was Co2+ > Mn2+ > Cu2+ > Zn2+. With coexistence of Cu2+, Zn2+ and Mn2+, the sequence was Co2+ > Cu2+ > Mn2+ > Zn2+. The interactions among ions had impact on the formation of ferrite.