Sun Xiaomin, Sun Tingli, Zhang Qingzhu, Wang Wenxing
Environment Research Institute, Shandong University, Jinan 250100, PR China.
Sci Total Environ. 2008 Aug 25;402(1):123-9. doi: 10.1016/j.scitotenv.2008.04.038.
A detailed understanding of the degradation mechanism of polychlorinated dibenzo-p-dioxins (PCDDs) is of great necessity. In wastewater treatment, an important degradation process of PCDDs ascribes to its reaction with the photo-Fenton reagent. In this paper, the reaction of 2,3,7,8-TeCDD with OH radicals has been studied using high level molecular orbital theory. The profile of the potential energy surface is constructed. A complete description of the possible degradation mechanism in solution is provided. Two degradation mechanisms are proposed: ring-opening and adducting mechanism, adducting and ring-opening mechanism. The main products obtained are 4,5-dichlorinate-o-dihydroxybenzene and 4,5-dichlorinate-o-quinone. The study on the quantitative structure-activity relationship of these PCDDs is performed. The structure-activity model has been constructed, in which three structural parameters, RO5-C12, RO5-C13 and QC14, are found to be positively correlated to the degradation activities.
