Abstract

The mechanism of aqueous contaminant removal by elemental (Fe 0 ) materials (e.g., in Fe 0 -H2O systems) has been largely discussed in the iron technology literature. Two major removal mechanisms are usually discussed: (i) contaminant adsorption onto Fe 0 oxidation products, and (ii) contaminant reduction by Fe 0 , Fe II or H/H2. However, a closer inspection of the chemistry of the Fe 0 -H2O system reveals that co-precipitation could be the primary removal mechanism. The plausibility of contaminant co-precipitation with corrosion products as independent contaminant re- moval mechanism is discussed here. It shows that the current concept does not take into account that the corrosion product generation is a dynamic process in the course of which contaminants are entrapped in the matrix of hydroxides. It is recalled that contaminant co-precipitation with hydroxides/oxides is an unspecific removal mechanism. Contaminant co-precipitation as primary removal mechanism is compatible with subsequent reduction and explains why redox- insensitive species are quantitatively removed. Adsorption and co-precipitation precede reduction and abiotic reduction, when it takes place, occurs independently by a direct (electrons from Fe 0 ) or an indirect (electrons from Fe II /H2) mecha- nism.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.