Characterization and mobility enhanchement of iron nanopowders suspensions for groundwater remediation

In the context of groundwater remediation, the use of zero-valent metals has been shown promising for the degradation of a wide range of contaminants. In particular, granular iron filings in permeable reactive barriers (PRBs) are a consolidated technology applied on a number of sites. Nanoscale zerovalent iron is characterized by tiny particles (1-100 nm) and by a specific surface area that is up to a hundred times higher than millimetric iron, thus also its reactivity is much higher. These particles can be suspended into a slurry and injected directly into the source of contamination in order to treat a wide variety of contaminants and bypassing most of the limitation related to PRBs. However, very limited or no mobility of the nanoparticles has been shown in both laboratory studies and field-scale tests. In the present study, after a description of the characterization of a commercial NZVI, the stabilizing effects and mobility enhancements deriving from dosing of biodegradable hydrocolloids on nanoscale iron suspensions will be investigated.