Rapid formation of polychlorinated dioxins/furans during the heterogeneous combustion of 1,2-dichlorobenzene and 2,4-dichlorophenol

The formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in a heterogeneous spouted bed combustor occurred within seconds from the oxidation of two different precursors; 1,2-dichlorobenzene and 2,4-dichlorophenol. Levels of PCDD/Fs produced from 2,4-dichlorophenol were two orders of magnitude higher than those produced from 1,2-dichlorobenzene, indicating that PCDD/Fs formation rate is much faster from chlorophenol precursors. In agreement with typical incinerator observations, the ratio of dioxins to furans was less than one from both precursors. Formation of chlorobenzenes and chlorophenols (other than the starting fuels) also occurred in the combustor; their concentration levels did not exhibit a strong dependence on the type of the precursors.