Metallic Iron for Water Treatment: A Critical Review

Water treatment with metallic iron (Fe-0) is still based on the premise that Fe-0 is a reducing agent. An alternative concept stipulates that contaminants are removed by adsorption, co-precipitation, and size-exclusion in a reactive filtration process. This article underlines the universal validity of the alternative concept. It is shown that admixing non-expansive material to Fe-0 as a pre-requisite for sustainable Fe-0-based filtration systems. Fe-0-based filters are demonstrated an affordable, appropriate, and efficient decentralized water treatment technology.