The direct and sensitized photo-oxidation of hexachlorocyclopentadiene

摘要: Abstract Hexachlorocyclopentadiene (C5Cl6) is an intermediate in the production of cyclodiene pesticides and flame retardants. To test treatability a chemical waste stream, hexachlorocyclopentadiene was tested as substrate for direct photolysis sensitized photo-oxidation this laboratory study. The initial concentration 100 mg/l aqueous buffers. Direct experiments were at pH values 5, 7.4, 9.2, 11. Riboflavin methylene blue used sensitizers. Samples batch reactors exposed to Durotest Vitalite® lights decreased all samples. Based on first order kinetic rates photodegradation hexachlorocyclopentadiene, riboflavin 5 best removal treatment, with average photodegradative half-life 47 min after light exposure compared laboratory. This corresponds quantum yields 0.76 0.49, respectively. Four photoproduct peaks identified by GC/MS analysis chloride extracts. major samples hexachlorocyclopentenone (C5Cl6O). compound containing C4Cl4, either tetrachlorobutadiene (C4H2Cl4) or tetrachlorobutyne (C4Cl4).