ABIOTIC AND BIOTIC FACTORS AFFECTING CONTAMINANT TRANSFORMATION AT IRON OXIDE SURFACES (Cosponsored with the Division of Geochemistry)

Introduction The current interest in iron/iron oxide nanoparticles for remediation applications can be partly attributed to their presumed ease of injection and faster reactivity. However, several processes can limit their effectiveness for degrading contaminants in groundwater include aging, aggregation and deposition. Under environmental conditions, nanoparticles with Fe(0) cores persist because they are passivated by a shell of oxide. The nature, structure and thickness of the oxide shell evolve with time due to reaction of the shell material with the core and with the external medium. Since the oxide shell usually mediates the reaction with contaminants, aging of the shell can affect the long-term performance of iron/iron oxide nanoparticles in remediation applications.