Zero-Valent Iron Nanoparticles for Soil and Groundwater Remediation

Abstract

Zero-valent iron has been reported as a successful remediation agent for environmental issues, being extensively used in soil and groundwater remediation. The use of zero-valent nanoparticles have been arisen as a highly effective method due to the high specific surface area of zero-valent nanoparticles. Then, the development of nanosized materials in general, and the improvement of the properties of the nano-iron in particular, has facilitated their application in remediation technologies. As the result, highly efficient and versatile nanomaterials have been obtained. Among the possible nanoparticle systems, the reactivity and availability of zero-valent iron nanoparticles (NZVI) have achieved very interesting and promising results make them particularly attractive for the remediation of subsurface contaminants. In fact, a large number of laboratory and pilot studies have reported the high effectiveness of these NZVI-based technologies for the remediation of groundwater and contaminated soils. Although the results are often based on a limited contaminant target, there is a large gap between the amount of contaminants tested with NZVI at the laboratory level and those remediated at the pilot and field level. In this review, the main zero-valent iron nanoparticles and their remediation capacity are summarized, in addition to the pilot and land scale studies reported until date for each kind of nanomaterials.

Agro-Pollutants and their Nano-Remediation from Soil and Water: A Mini-Review

“…Guerra et al (2018) classified the nanomaterials used for environmental remediation into three main categories to include inorganic (metal and metal oxide-based nanomaterials like Ag-NPs, TiO 2 -NPs, iron-based nanoparticles), carbon-based (fullerene C 60 , fullerene C 540 , graphene, single-walled nanotubes and multiwalled nanotubes), polymeric-based materials (e.g., amphiphilic polyurethane NPs, polyaminemodified cellulose and polymer nanocomposites) and silica nanomaterials or silica-graphene porous nanocomposites (Thakkar and Malfatti, 2021). Important nanomaterials used in soil and water remediation include nano-silica (Jeelani et al 2020) and zero-valent iron nanoparticles (Galdames et al 2020).…”

Recent Advances of Nanoremediation Technologies for Soil and Groundwater Remediation: A Review

“…The use of nanomaterials for soil and groundwater remediation has been widely tested at the laboratory level against a large number of contaminants, offering promising results [23,24]. However, nanomaterials may pose positive or negative impacts on living organisms, the environment, society, and the economy, which should be evaluated in a case-specific context.…”

Rapid Degradation of Carbon Tetrachloride by Microscale Ag/Fe Bimetallic Particles

“…The application of zero valent iron (ZVI) for environmental remediation of soil and groundwater has been widely studied for more than two decades [ 1 ]. Nanoscale zero valent iron (nZVI) exhibits better performance in contaminant removal compared with the microscale ZVI, because nZVI has a larger surface area and higher reactivity due to its small size [ 2 ]. Therefore, a wide range of contaminants can be effectively removed by nZVI, such as chlorinated solvents, phenols, pesticides, heavy metals, arsenite, nitrate, etc.…”

“…Therefore, a wide range of contaminants can be effectively removed by nZVI, such as chlorinated solvents, phenols, pesticides, heavy metals, arsenite, nitrate, etc. [ 1 , 2 , 3 ]. However, limited mobility of the unmodified nZVI, the rapid aggregation of particles, fast corrosion rate in water, high cost of nZVI production, and potential ecotoxicity restrict its application for contaminant removal [ 3 , 4 ].…”

“…Less-expensive microscale iron particles (mZVI) have been considered as an alternative for nZVI [ 5 , 6 , 7 ]. Compared with nZVI, the use of mZVI in field applications has some advantages, such as a longer lifetime, easier and safer handling of dry particles, lower commercial costs, and lower potential toxicity to the ecosystem [ 2 , 8 , 9 ]. It was reported that the reactivity of some newly designed mZVIs was similar to highly reactive nZVIs, and even up to one order of magnitude higher according to specific surface-area-normalized reaction rate constants under standardized experimental conditions [ 6 ], while the mZVI particles had approximately a 10–30-fold lower corrosion rate than nZVI particles [ 7 ].…”