(20f) Environmental Remediation of Dense Non-Aqueous-Phase Liquids Using Multifunctional Nanoparticles
Dense non-aqueous-phase liquids (DNAPLs) such as trichloroethylene (TCE), settle deep into sediment, contaminating soil and groundwater causing long-term environmental pollution. Nanoscale zero-valent iron particles (nZVI) are a preferred option for in-situ injection for groundwater remediation due to their high efficiency, low cost and environmentally benign nature. However, bare nZVI particles aggregate, limiting their mobility through subsurface. This study describes the use of a novel zero-valent iron based technology to facilitate the in-situ remediation of chlorinated hydrocarbons. We describe the synthesis of colloidal carbon microspheres supported with zero-valent iron nanoparticles using a simple one-step process and with inexpensive precursors. The multifunctionality of these systems is based on their reactivity, adsorptive capabilities, efficient transport, colloidal stability and partitioning to bulk phases of DNAPLs. Scale up to manufacturing levels is entirely feasible as the process is semi-continuous. The presentation will focus on detailed characterization of these multifunctional composites through high resolution electron microscopy and their functional properties. The significant aspects ? adsorption, transport and reaction of these multifunctional nanoparticles in remediation of groundwater contaminants ? will be discussed.