Print Email Facebook Twitter Fate and transport of sulfidated nano zerovalent iron (S-nZVI): A field study Title Fate and transport of sulfidated nano zerovalent iron (S-nZVI): A field study Author Garcia, A. Nunez Boparai, H.K. de Boer, C.V. Chowdhury, A.I.A. Kocur, C.M.D. Austrins, L.M. Herrera, J. O'Carroll, D.M. Publication year 2020 Abstract Treatment of nano zerovalent iron (nZVI) with lower valent forms of sulfur compounds (sulfidation) has the potential to increase the selectivity and reactivity of nZVI with target contaminants and to decrease inter-particle aggregation for improving its mobility. These developments help in addressing some of the long-standing challenges associated with nZVI-based remediation treatments and are of great interest for in situ applications. Herein we report results from a field-scale project conducted at a contaminated site. Sulfidated nZVI (S-nZVI) was prepared on site by first synthesizing carboxymethyl cellulose (CMC) stabilized nZVI with sodium borohydride as a reductant and then sulfidating the nZVI suspension by adding sodium dithionite. Transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDS) of CMC-S-nZVI, from synthesis barrels, confirms the presence of both discrete spherical nZVI-like particles (∼90 nm) as well as larger irregular structures (∼500 nm) comprising of iron sulfides. This CMC-S-nZVI suspension was gravity fed into a sandy material and monitored through multiple multi-level monitoring wells. Samples collected from upstream and downstream wells suggest very good radial and vertical iron distribution. TEM-EDS analysis from the recovered well samples also indicates the presence of both nZVI-like particles as well as the larger flake-like structures, similar to those found in the injected CMC-S-nZVI suspension. This study shows that S-nZVI stabilized with CMC can be safely synthesized on site and is highly mobile and stable in the subsurface, demonstrating for the first time the field applicability of S-nZVI. © 2019 Elsevier Ltd Subject Geological Survey Netherlands2015 EnergyCharacterizationDithioniteField applicationNano zerovalent ironSubsurface transportSulfidation To reference this document use: http://resolver.tudelft.nl/uuid:e67b1712-4ef7-41a7-98d0-ee850af62497 DOI https://doi.org/10.1016/j.watres.2019.115319 TNO identifier 870495 Publisher Elsevier Ltd ISSN 0043-1354 Source Water Research, 170, 1-10 Article number 115319 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.