Degradation of toxic halogenated organic compounds by iron-containing mono-, bi- and tri-metallic particles in water

Contamination of surface water, groundwater and soil by halogenated organic compounds (HOCs) is a major problem of our society. HOCs have been used in a wide variety of applications and their presence as water contaminant is now a serious issue because of their toxicity, persistence and potential accumulation in plants and animal tissues. Transformation of HOCs by zero-valent iron represents a promising technology for environmental remediation. This mini-review outlines how iron particles are able to degrade toxic HOCs in water. It shows how the addition of one or two metals, such as palladium, copper, silver and nickel, to form bi- and tri-metallic particles can lead to a more efficient decontamination. Other ways to enhance the degradation of HOCs are the use of additives and ultrasounds. Another interesting approach is to anchor the metallic particles on various supports. Examples of the various approaches are given.