Ferrates for water remediation

The availability of safe drinking-water at the global level is one of the biggest challenges of our century. At present, toxins and pathogens in fresh waters are responsible for more than two million deaths per year. This scenario allows understanding how the development of effective and sustainable technologies for water treatment is of pivotal importance for future generations. A number of different agents and methods are used for water purification and environmental remediation, however they all show main drawbacks, revealing the need for a major technological advancement. Iron-based materials are earning a particular interest due to the effectiveness in water purification, the environmental friendly and earth-abundant nature. Moreover, some iron-containing materials are magnetic, allowing for an easy removal of the materials after water sanitizations. In the present review, the state of the art of iron based nanomaterials for water remediation is presented, with a special attention on ferrates, their synthesis, stability, mechanism of action and analytical determination. More in details, the review focuses on the following environmental applications of iron based nanomaterials: wastewater disinfection, organic matter removal, treatment of pharmaceuticals, inactivation of bacteria and viruses, removal of heavy metals and arsenic, degradation of fluoro-compounds and inactivation of cyanobacteria.