Surface-modified iron and iron oxide nanoparticles for enhanced remediation of U(VI)-containing groundwater
Iron nanoparticles have applications for the remediation of contaminated groundwater. Fe(III) nanoparticles can enhance iron reducing bacteria that also reduce and immobilize uranium. Fe(0) nanoparticles are effective reductants for the dehalogenation of chlorinated solvents and reduction of Cr(VI), and also U(VI) under anoxic conditions. The breakthrough needed to transform this technology is to be able to deliver such particles into the groundwater formation at distances of tens of meters away from the injection site. We propose to develop Fe(III) and Fe(0) nanoparticles with polymer coatings that minimize interactions with and filtration by soil, without deteriorating their reactive properties. Initial work will focus on modifications of Fe(III) nanoparticles using anionic polyelectrolytes. We will conduct filtration experiments to determine the coatings’ effect on nanoparticle transport in soils, and batch experiments will determine how the coating affects the nanoparticle’s reactivity. These results will then be used to optimize new coating compositions and strategies.