The application and mechanism of iron sulfides in arsenic removal from water and wastewater: A critical review

• Published in: Journal of environmental chemical engineering 2022-12, Vol.10 (6), p.108856, Article 108856
• Main Authors: Zhang, Xingfei, Fan, Huan, Yuan, Jia, Tian, Jia, Wang, Yufeng, Lu, Chenglong, Han, Haisheng, Sun, Wei
• Format: Article
• Language: English
• Subjects: Adsorption; Arsenic removal; Iron sulfides; Nanoparticles; Wastewater
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2022.108856

Over the last decades, a large amount of arsenic-containing wastewater discharged by industries has seriously polluted groundwater and drinking water, resulting in the number of arsenicosis patients increasing day by day. Iron sulfides are considered promising for effective arsenic removal from water/wastewater due to their exclusive physical and chemical properties. The applications of various iron sulfides materials, including natural pyrite and pyrrhotite, modified pyrite, nanostructure FeS and FeS2, in arsenic removal from aqueous solution are summarized. The present review paper mainly analyzes the performance and influencing factors of iron sulfides in arsenic removal, the synthetic conditions of nanoparticles, and their limitations. pH and temperature are the two main factors affecting the removal efficiency of arsenic in low arsenic-containing water. It is necessary to modify natural iron sulfide or synthesize FeS, which will significantly enhance the reactivity of iron sulfides in high concentration arsenic-containing wastewater. The mechanisms behind the arsenite and arsenate removal by iron sulfides are discussed in detail. Adsorption and precipitation are the primary removal mechanisms of low concentration and high concentration arsenic-containing wastewater, respectively. Future needs in arsenic removal technology using iron sulfides are also proposed. Overall, iron sulfides offer considerable potential towards powerfully removing arsenic in both low and high concentrations of water/wastewater. [Display omitted] •The applications of various iron sulfides materials in arsenic removal are summarized.•The crystal structure and specific surface area influence the reactivity of iron sulfides.•The synthetic methods and performance of nanostructure iron sulfide are reviewed.•The mechanism of iron sulfides in removing arsenic is described.•Research in high As wastewater with high-activity iron sulfides is needed.