Abstract
Although PCBs have been known to be remarkably stable, they are completely decomposed in alakline alcoholic solution by UV- or Gamma-Irradiation. Their dechlorinations are characteristic of a chain reaction. PCBs are decomposed by following two reactions :
(1) Homolytic fission of carbon-chlorine bond at photoexcited state.
(2) Decomposition of radical anion of PCBs to phenyl radical and chloride ion.
Various attempts have been made to establish an effective and safety decomposition process of PCBs since high reaction quantum yield (40 for KC-300) was found in the above reaction.
This brief review is then concerned with dechlorination behaviors of PCBs, almost of which have been clarified through the studies of chain degradative dechlorination of PCBs, and also a proposed photochemical reactor design.
