Application of iron-based materials for removal of antimony and arsenic from water: Sorption properties and mechanism insights

Antimony (Sb) and arsenic (As) pollution in water has become a major concern in the world due to their toxicity and adverse effects to environmental quality and human health. Among the existing remediation technologies for Sb and As pollution control, sorption via iron-based materials has attracted increasing attention since they possess advantages of great affinity towards Sb and As, low cost, strong reactivity, and easy preparation and recycling. This paper provided a comprehensive overview on the application of a variety of iron-based materials, namely, zero valent iron, iron oxides, and iron-based bimetal oxides, for aqueous Sb and As remediation. Strategies to improve the dispersion, stability, and reactivity of iron-based materials such as nano-scale size control and mechanical support, are discussed. The removal effectiveness, underlying mechanisms, regeneration performance, and environmental impacts of various iron-based materials for aqueous Sb and As are summarized. Various analytical methods for quantitative analysis of Sb and As and characterization of interactions between Sb/As and iron-based materials are also discussed. Finally, current knowledge gaps and future research needs are identified to facilitate a better understanding of molecular-level reaction mechanisms between iron-based materials and Sb/As and to advance the large-scale application of this remediation technology.