PHOTODECHLORINATION OF MONOCHLOROBENZENES AND POLYCHLOROBENZENES BY REDUCTIVE PHOTOSENSITIZATION

Redox photosensitization was used to reduce mono and polychlorobenzene s with the electron-donor photosensitizers N,N,N',N'-tetramethyl-p-phe nylenediamine (NTMP), N,N,N',N'-tetramethylbenzidine (NTMB), 3-dimethy laminophenol (NDMP) and 2-methoxyphenol (MEOP). The excited state ener gies of the photosensitizers and the redox potentials of the donor-acc eptor couples show that the reductive electron transfer from the excit ed photosensitizers to the substrates is thermodynamically feasible. T he results show that an electron-donor photosensitizer may increase th e rate of dehalogenation of haloaromatic residues in the environment.