title: Impact of carbon, oxygen and sulfur content of microscale zerovalent iron particles on its reactivity towards chlorinated aliphatic hydrocarbons.
abstract: Zerovalent iron (ZVI) abiotically degrades several chlorinated aliphatic hydrocarbons (CAHs) via reductive dechlorination, which offers perspectives for in situ groundwater remediation applications. The difference in reactivity between ZVI particles is often linked with their specific surface area. However, other parameters may influence the reactivity as well. Earlier, we reported for a set of microscale zerovalent iron (mZVI) particles the disappearance kinetic of different CAHs which were collected under consistent experimental conditions. In the present study, these kinetic data were correlated with the carbon, oxygen and sulfur content of mZVI particles. It was confirmed that not only the specific surface area affects the disappearance kinetic of CAHs, but also the chemical composition of the mZVI particles. The chemical composition, in addition, influences CAHs removal mechanism inducing sorption onto mZVI particles instead of dechlorination. Generally, high disappearance kinetic of CAHs was observed for particles containing less oxygen. A high carbon content, on the other hand, induced nonreactive sorption of the contaminants on the mZVI particles. To obtain efficient remediation of CAHs by mZVI particles, this study suggested that the carbon and oxygen content should not exceed 0.5% and 1% respectively. Finally, the efficiency of the mZVI particles may be improved to some extent by enriching them with sulfur. However, the impact of sulfur content on the reactivity of mZVI particles is less pronounced than that of the carbon and oxygen content.
authors: Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium; University of Antwerp, Department of Bio-Engineering, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors: Milica
authors: M
authors: Velimirovic
authors: Per-Olof
authors: PO
authors: Larsson
authors: Queenie
authors: Q
authors: Simons
authors: Leen
authors: L
authors: Bastiaens
mesh_terms: D002244:Carbon / Q000737:chemistry; D052918:Environmental Restoration and Remediation / Q000379:methods*; D060587:Groundwater / Q000737:chemistry; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D010100:Oxygen / Q000737:chemistry; D010316:Particle Size; D013455:Sulfur / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D006838:Hydrocarbons; D014874:Water Pollutants, Chemical; D013455:Sulfur; D002244:Carbon; D007501:Iron; D010100:Oxygen
keywords: C, O, S content; CAHs disappearance rate; Microscale zerovalent iron; Particles composition