Formation Pathways of Mono- to Octa-Chlorinated Dibenzo-p-dioxins and Dibenzofurans in Main Organochemical Industries

Abstract

The concentrations and formation pathways of mono-to octa-chlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were investigated in main organochemical industries. High levels of PCDDs and PCDFs were detected. The total concentrations of 27 PCDD/F congeners in chloranil, 2,4-D, and 1,4-dichlorobenzene were 5302397 ± 8944449, 20963 ± 15908, and 242 ± 67 pg g −1 , respectively, and the less-chlorinated PCDD/F levels were 12006 ± 20155, 9536 ± 5594, and 195 ± 94 pg g −1 , respectively. The distribution trends of less and more chlorinated PCDD/Fs were similar in different chemical plants because of their similar formation pathways, which may also be related to the degree of chlorination of chemical products and purification processes.

Mono- to Octachlorinated Polychlorinated Dibenzo-p-dioxin and Dibenzofuran Emissions from Sintering Plants Synergistically Controlled by the Desulfurization Process

“…These congeners have also been found to be very dominant in samples collected in waste incineration and organic chemical plants. 14,18 This was attributed to positions 2, 4, and 8 of the PCDF ring having relatively low bond dissociation energies. 17 2,3-DiCDD and 1-MoCDD contributed 1.5−3.6 and 1.3−4.3%, respectively, of the total PCDD/Fs concentrations.…”

Gas-Particle Partitioning of Polychlorinated Dibenzo-p-dioxins, Dibenzofurans, and Biphenyls in Flue Gases from Municipal Solid Waste Incinerators

“…According to the calculations for bond dissociation energy, 2-C and 3-C bonds in the PCDD/F structures are more easily chlorinated (Han et al, 2015). This suggests that the non-2,3,7,8-chlorinated PCDD/F compounds described above could be easily chlorinated to 2-C-Cl and 3-C-Cl forms.…”

Influence of long-range atmospheric transportation (LRAT) on mono-to octa-chlorinated PCDD/Fs levels and distributions in soil around Qinghai Lake, China

“…Soil samples were freeze-dried for 24 h, passed through a 60-mesh sieve and then analyzed. Pretreatment and analysis of the PCDD/Fs were performed according to standard method US EPA-1613, which has been described in previous studies (Han et al, 2015;Kim et al, 2009;L'Homme et al, 2015;Liu et al, 2012;Morales et al, 2014;Venkatesan and Halden, 2014;Weidemann et al, 2014;Weidemann and Lundin, 2015).…”