An innovative full-scale implementation of a permeable reactive barrier, consisting of a double-row of cylinders filled with zerovalent iron shavings, for chromate remediation was monitored over four years. Solid samples were analyzed to elucidate (i) the relevant corrosion mechanisms and products, (ii) the pathways of chromate reduction and immobilization, and (iii) the long-term performance o...

The applications of zerovalent iron nanoparticles in environmental remediation have led to the development of green methods in their synthesis. This study for the first time reports on the green synthesis of zerovalent iron nanoparticles using Thuja orientalis extract as the reducing and capping agent at room temperature. The synthesized nanoparticles were characterized with different tec...

Chlorinated solvents in the subsurface are a widespread problem with thousands of impacted sites in the United States. A large body of literature exists that evaluates treatment of chlorinated solvents using granular zero valent iron, which has been shown to treat chlorinated solvents via reductive dechlorination. Much of this literature is conducted within the context of permeable reactive bar...

Zero valent iron (ZVI), the primary reactive material in several permeable reactive barriers, is often oxidized to ferrous or ferric iron, resulting in decreased reactivity with time. Iron reducing bacteria can reconvert the ferric iron to its ferrous form, prolonging the reduction of chlorinated organic contaminants. In this study, the reduction of Fe(II,III) oxide and Fe(III) oxide by a strai...

This study demonstrated the synergistic degradation of 4-chlorophenol (4-CP) achieved in a magnetic field (MF) enhanced zero-valent iron (ZVI)/H2O2 Fenton-like (FL) system and revealed an interesting correlative dependence relationship between MF and the pristine iron oxides layer (FexOy) on ZVI particles. First, a comparative investigation between the FL and MF-FL systems was conducted under d...

Zero-valent iron (ZVI) application in groundwater remediation is limited by its vulnerability to passivation, which significantly decreases its surface reactivity. Both biological and chemical processes can potentially passivate ZVI, although the understanding of biological passivation is limited. This study was conducted in bench-scale reactors packed with fresh ZVI or ZVI pre-exposed to nitra...

A standardized batch test procedure was developed and used to evaluate the reactivity of twelve newly designed microscale zerovalent iron (mZVI) particles and two biogenic iron sulfides towards a mixture of chlorinated aliphatic hydrocarbons (CAHs) and their breakdown products. For comparison, commercially available mZVIs, nanoscale zerovalent irons (nZVIs), iron sulfides (FeS) and granular zer...

EHC ® is an integrated combination of controlled-release plant-derived carbon plus micro-scale zero valent iron (ZVI) particles used for stimulating in situ chemical reduction of otherwise persistent organic compounds in groundwater. EHC-M ® uses the same combination plus a source of sulphate (if needed) to promote the precipitation of dissolved metals. In evaluating the longevity of EHC, sever...

A laboratory investigation provided preliminary comparison of trace element contaminant water treatment capabilities for four iron-based filter materials. The iron-based filter materials tested were zero-valent iron (ZVI), porous iron composite (PIC), sulfur modified iron (SMI), and iron oxide/hydroxide (IOH). Two types of trace element contaminant solutions were tested, one combined As, Cr, an...