Zero-valent iron for water treatment

The use of zero-valent iron in the treatment of hazardous water contaminant s is reviewed. The review concentrates on experimental procedures employed in the investigation of a range of applications for zero-valent iron and th e efficacy of the processes. Investigations reviewed include those performe d with halogenated aliphatic compounds, halogenated aromatic compounds, nit ro-aromatic organic compounds, and high-valency toxic metals. Experiments e mploying bimetallic and cementation reductants as well as zero-valent iron alone are covered. The need for zero-valent iron technology is discussed, a s is the need for more rigorous investigation of operational parameters. De spite a paucity of information from the literature it has been shown that e fficacy is greatest for well-mired batch or continuous column systems emplo ying neutral to acidic pH and a high specific surface area of iron. The lit erature also reveals a need to focus future work on enhancing the chemical reaction taking place on the iron surface in order to enhance the rate of r eductive remediation.