Synergistic adsorption and oxidation of trivalent antimony from groundwater using biochar supported magnesium ferrite: Performances and mechanisms

• Published in: Environmental pollution (1987) Vol. 323; p. 121318
• Main Authors: Yao, Bin, Li, Yixiang, Zeng, Wenqing, Yang, Guang, Zeng, Jiahao, Nie, Jing, Zhou, Yaoyu
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.04.2023
• Subjects: Adsorption; Antimony; Dynamic adsorption; Groundwater; Humans; Magnetic biochar; Oxidation; Oxidation-Reduction; Sb(III); Water Pollutants, Chemical; Dynamic adsorption; Oxidation; Magnetic biochar; Adsorption; Sb(III)
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2023.121318

Antimony (Sb) pollution is considered an environmental problem, since Sb is toxic and carcinogenic to humans. Here, a novel biochar supported magnesium ferrite (BC@MF) was adopted for Sb(III) removal from groundwater. The maximum adsorption capacity was 77.44 mg g−1. Together with characterization, batch experiments, kinetics, isotherms, and thermodynamic analyses suggested that inner-sphere complexation, H–bonding, and electrostatic interactions were the primary mechanisms. C–C/CC, C–O, and O–CO groups and Fe/Mg oxides might have acted as adsorption sites. The adsorbed Sb(III) was oxidized to Sb(V). The generation of reactive oxygen species, iron redox reaction, and oxidizing functional groups all contributed to Sb(III) oxidation. Furthermore, the fixed-bed column system demonstrated a satisfactory Sb removal performance; BC@MF could treat ∼6060 BV of simulated Sb-polluted groundwater. This research provides a promising approach to sufficiently remove Sb(III) from contaminated groundwater, providing new insights for the development of innovative strategies for heavy metal removal. •Functional groups and Fe/Mg species were adsorption sites.•Inner-sphere complex, H-bond, and electrostatic force jointly drove adsorption.•Sb(III) oxidization involved in ROS, iron redox, and oxidizing functional groups.•BC@MF300 exhibited fantastic removal performance in column studies.