title: Formation of persistent organic pollutants from 2,4,5-trichlorothiophenol combustion: a density functional theory investigation.
abstract: Polychlorinated dibenzothiophene (PCDT) and polychlorinated thianthrene (PCTA) are sulfur analogues of dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F). In this work, we present a detailed mechanistic and kinetic analysis of PCDT and PCTA formation from the combustion of 2,4,5-trichlorothiophenol. It is shown that the formation of these persistent organic pollutants is more favourable, both kinetically and thermodynamically, than their analogous dioxin counterparts. This is rationalised in terms of the different influences of the S-H and O-H moieties in the 2,4,5-trichlorothiophenol and 2,4,5-trichlorophenol precursors. Kinetic parameters also indicate that the yield of PCDT should exceed that of PCDD. Finally, we demonstrate here that the degree and pattern of chlorination on the 2,4,5-trichlorothiophenol precursor leads to subtle thermodynamic and kinetic changes to the PCDT/PCTA formation mechanisms. Graphical abstract Formation mechanisms of persistant organic pollutants, PCDT and PCTA, from 2,4,5-trichlorothiophenol combustion, has been investigated using density functional theory.
authors.affiliation: Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW, 2308, Australia.
authors.forename: Tajwar
authors.initials: T
authors.lastname: Dar
authors.affiliation: Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW, 2308, Australia.
authors.forename: Kalpit
authors.initials: K
authors.lastname: Shah
authors.affiliation: Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW, 2308, Australia.
authors.forename: Behdad
authors.initials: B
authors.lastname: Moghtaderi
authors.affiliation: Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW, 2308, Australia. alister.page@newcastle.edu.au.
authors.forename: Alister J
authors.initials: AJ
authors.lastname: Page
mesh_terms: D002733:Chlorophenols / Q000737:chemistry*; D019281:Dimerization; D004785:Environmental Pollutants / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000737:chemistry; D006358:Hot Temperature; D007536:Isomerism; D007700:Kinetics; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D000072317:Polychlorinated Dibenzodioxins / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013816:Thermodynamics; D013876:Thiophenes / Q000737:chemistry
chemical_list: D002733:Chlorophenols; D004785:Environmental Pollutants; D006571:Heterocyclic Compounds; D000072317:Polychlorinated Dibenzodioxins; D013438:Sulfhydryl Compounds; D013876:Thiophenes; C009534:2,4,5-trichlorophenol; C035301:2,4,5-trichlorothiophenol; C009449:thianthrene; C016366:dibenzothiophene
keywords: Chlorinated; Combustion; Dibenzot hiophene; Dioxin; Persistent organic pollutant; Thianthrene