ABSTRACT
Considerable controversy regarding the participation of different iron species in the reductive dechlorination of trichloroethene (TCE) has lead to the development of several hypotheses. In all cases, the iron donates the electrons which are subsequently accepted by the TCE and leads to the release of chloride and the formation of the dechlorinated product(s). These products includes di-chloroethene and vinyl chloride, and possible non-chlorinated alkanes. This chapter examines the potential reactivity of different iron species with regard to their participation in the reductive dechlorination of TCE. The different iron species tested provided a wide range of reactivity in part due to the iron species in question and in part due to the conditions of the test. If the TCE was completely degraded, one would expect an equivalent of three moles of chloride for every mole of TCE degraded, but if all the TCE is degraded only to di-chloroethene, then only one mole of chloride per mole of TCE is expected.
