The Dechlorination of Hydrocarbons

The pollution of groundwater and soils by industrial chemicals is a cause of significant environmental concern. Treatment with palladium is suggested as a means of decontaminating certain occurrences of polluted soil and groundwater. Palladium can be chemically deposited onto zero-valence iron (Fe⁰) and the resulting bimetal is very effective in dechlorinating many of the toxic chemicals, produced as industrial effluents, that are found in soils and groundwater. With a palladium content of 0.05 per cent (w/w), the rate at which trichloroethene is dechlorinated is one to two orders of magnitude faster than with iron alone. Similarly, a bimetal made of palladium/iron readily dechlorinates dichloromethane and polychlorinated biphenyls which are not easily reduced by Fe⁰.