The Suitability of Metallic Iron for Environmental Remediation: Back to The Origin

Aqueous contaminant removal in the presence of metallic iron is often regarded as a reductive transformation mediated by the Fe surface. However, successful removal of theoretically non-reducible contaminants has been largely reported. This paper presents a rebuttal of the concept of contaminant reductive transformation. It is argued through a careful examination of the evolution of the volume and adsorptive properties of iron and its corrosion products that contaminants are primarily adsorbed and co-precipitated with iron corrosion products. One may wonder how the Fe technology will develop with the new concept.