Modification, application and reaction mechanisms of nano-sized iron sulfide particles for pollutant removal from soil and water: A review

The presence of excessive pollutants in soil and water caused by the fast development of industry has been a challenge for the innovation of environmental remediation technologies. Nano-sized iron sulfide (FeS) particles have aroused researchers' attention for environmental remediation over the decade owing to their high reactivity and large specific surface area. The aim of this paper is to provide a comprehensive review on the evolution of FeS nanoparticles for environmental decontamination. The synthesis for bare nano-sized FeS particles via physicochemical and biological methods, the modification for nano-sized FeS particles by coating stabilizers and loading supporting materials are described in this review. What's more, the applications of nano-scale FeS in soil and water remediation are also discussed, including the removal of halogenated hydrocarbon, radionuclide, heavy metals, and metalloid. Meanwhile, the interaction mechanisms, namely adsorption and redox reaction between contaminants and nano-sized FeS and the effect of remediation conditions have been summarized in this review. Moreover, some future research needs are also stated such as researching the fate of FeS nanoparticle after injecting into soil and water, enhancing the mobility of nano-sized FeS in soil and water, and measuring the toxicity to the organisms.