title: Enhanced transport of Si-coated nanoscale zero-valent iron particles in porous media.
abstract: Laboratory column experiments were conducted to evaluate the effect of previously described silica coating method on the transport of nanoscale zero-valent iron (nZVI) in porous media. The silica coating method showed the potential to prevent the agglomeration of nZVI. Transport experiments were conducted using laboratory-scale sand-packed columns at conditions that were very similar of natural groundwater. Transport properties of non-coated and silica-coated nZVI are investigated in columns of 40 cm length, which were filled with porous media. A suspension was injected in three different Fe particle concentrations (100, 500, and 1000 mg/L) at flow 5  mL/min. Experimental results were compared using nanoparticle attachment efficiency and travel distances which were calculated by classical particle filtration theory. It was found that non-coated particles were essentially immobile in porous media. In contrast, silica-coated particles showed significant transport distances at the tested conditions. Results of this study suggest that silica can increase nZVI mobility in the subsurface.
authors.affiliation: a Department of Environmental Chemistry , University of Chemistry and Technology Prague , Prague , Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: HonetschlÄgerová
authors.affiliation: a Department of Environmental Chemistry , University of Chemistry and Technology Prague , Prague , Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Janouškovcová
authors.affiliation: a Department of Environmental Chemistry , University of Chemistry and Technology Prague , Prague , Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Kubal
mesh_terms: D052918:Environmental Restoration and Remediation / Q000379:methods; D007501:Iron / Q000737:chemistry*; D008962:Models, Theoretical; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D012822:Silicon Dioxide; D007501:Iron
keywords: Nanoscale zero-valent iron; column experiments; mobility; porous media; remediation