Degradation of groundwater contaminants by iron containing systems.

Abstract

Iron-containing systems are effective at reducing common groundwater contaminants. Zero-valent iron particles are an effective remediation technology for groundwater contaminated with halogenated organic compounds. Iron salts were used to generate iron oxide nanoparticles, which were reduced to zero-valent iron. The reactivity of the resulting zero-valent iron nanoparticles was quantified by monitoring the kinetics of carbon tetrachloride reduction, and significant differences in reactivity were observed. Furthermore, substantial variations in the solid-state products of oxidation were also observed. Fe(II)-iron mineral systems are also an effective method for reducing nitroaromatic compounds, such as pesticides. The objective of this study was to link changes in the mineralogy of goethite particles to changes in the reactivity of an Fe(II)-goethite system. The reactivity of Fe(II)-goethite and Fe(II)-goethite sand systems were quantified by monitoring the kinetics of trifluralin reduction. Changes in the goethite mineralogy were observed by transmission electron microscopy. Differences in goethite reactivity and the solid-state products were observed, as compared to previous work using goethite.