title: Photodegradation of pentachlorophenol and its degradation pathways predicted using density functional theory.
abstract: The objectives of the present research were (i) to report the mass balance of chlorine during pentachlorophenol (PCP) photodegradation and (ii) to reveal the photodegradation pathway experimentally with a theoretical proof based on the density functional theory (DFT). The chlorine of PCP was completely mineralized to produce chloride ions after 24h of UV irradiation. As intermediates, 2,3,5,6-tetrachlorophenol, 2,3,4,6-tetrachlorophenol and 2,5-dichlorophenol were identified. At least 80% of the chlorine balance during PCP photodegradation was accounted by PCP, these intermediates, and chloride ions. A DFT calculation showed differences in the C-Cl bond dissociation energy level and the positions of respective PCP molecular and the PCP intermediates. The dechlorination intermediates predicted using the calculated C-Cl bond dissociation energy were consistent with those experimentally confirmed, indicating the feasibility of this theoretical method in predicting the dechlorination pathway.
authors.affiliation: Public Enterprises Agency, Kanagawa Prefectural Government, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Suegara
authors.forename: Byung-Dae
authors.initials: BD
authors.lastname: Lee
authors.forename: Maria P
authors.initials: MP
authors.lastname: Espino
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakai
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hosomi
mesh_terms: D005544:Forecasting; D007306:Insecticides / Q000737:chemistry*; D008956:Models, Chemical; D010416:Pentachlorophenol / Q000737:chemistry*; D010777:Photochemistry; D018508:Water Purification
chemical_list: D007306:Insecticides; D010416:Pentachlorophenol