Study on Efficient Adsorption Mechanism of Pb(2+) by Magnetic Coconut Biochar

Lead ion (Pb(2+)) in wastewater cannot be biodegraded and destroyed. It can easily be enriched in living organisms, which causes serious harm to the environment and human health. Among the existing treatment technologies, adsorption is a green and efficient way to treat heavy metal contamination. Novel KMnO(4)-treated magnetic biochar (KFBC) was successfully synthesized by the addition of Fe(NO(3))(3) and KMnO(4) treatment during carbonization following Pb(2+) adsorption. SEM-EDS, XPS, and ICP-OES were used to evaluate the KFBC and magnetic biochar (FBC) on the surface morphology, surface chemistry characteristics, surface functional groups, and Pb(2+) adsorption behavior. The effects of pH on the Pb(2+) solution, initial concentration of Pb(2+), adsorption time, and influencing ions on the adsorption amount of Pb(2+) were examined, and the adsorption mechanisms of FBC and KFBC on Pb(2+) were investigated. The results showed that pH had a strong influence on the adsorption of KFBC and the optimum adsorption pH was 5. The saturation adsorption capacity fitted by the model was 170.668 mg/g. The successful loading of manganese oxides and the enhanced oxygen functional groups, as evidenced by XPS and FTIR data, improved KFBC for heavy metal adsorption. Mineral precipitation, functional group complexation, and π-electron interactions were the primary adsorption processes.