Qingdao Engineering Research Center for Rural Environment, College of Resource and Environment, Qingdao Agricultural University, Qingdao 266109, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
Key Laboratory of Biology and Genetic Improvement of Horticulture Crops (Northeast Region), Ministry of Agriculture and Rural Affairs, Northeast Agricultural University, Harbin 150078, China.
Sci Total Environ. 2021 Nov 25;797:149152. doi: 10.1016/j.scitotenv.2021.149152. Epub 2021 Jul 20.
Iodinated disinfection by-products (DBPs) have been attracting great attention due to their potential high toxicity to human health. Understanding of formation mechanisms and transformation process of iodinated aromatic DBPs during the chlorination of iodide-containing water is crucial. Phenol was therefore chosen as a representative of phenolic compounds to investigate the generation of iodinated aromatic DBPs in a chlorine/phenol/iodide system. The presence of iodide in water could enhance the removal of phenol by chlorine due to higher second order rate constants of HOI with phenol than that of HOCl with phenol. Fourteen kinds of iodinated aromatic DBPs were identified, which were generated from oxidation and electrophilic substitution of phenol by HOCl and HOI. Iodinated phenolic DBPs were sources of iodinated quinone DBPs and chlorinated/iodinated phenolic DBPs. Alkaline condition favored the formation of iodinated phenolic DBPs, while acid condition favored the production of iodinated quinone DBPs. Neutral condition might be the most suitable pH condition to control the formation of iodinated aromatic DBPs. The relative concentration of almost all iodinated aromatic DBPs first increased and then decreased with time, indicating iodinated aromatic DBPs might be further converted into halogenated aliphatic DBPs during the chlorination. This research provides a research basis for the removal of phenol in water.
含碘消毒副产物（DBPs）因其对人类健康的潜在高毒性而受到极大关注。了解含碘水中氯化过程中碘代芳香族 DBPs 的形成机制和转化过程至关重要。因此，选择苯酚作为酚类化合物的代表，以研究在氯/苯酚/碘化物体系中生成的碘代芳香族 DBPs。水中的碘化物的存在由于 HOI 与苯酚的二级反应速率常数高于 HOCl 与苯酚的二级反应速率常数，因此可以增强氯对苯酚的去除。鉴定出 14 种碘代芳香族 DBPs，这些 DBPs是由 HOCl 和 HOI 氧化和亲电取代苯酚生成的。碘代酚类 DBPs 是碘代醌 DBPs 和氯化/碘代酚类 DBPs 的来源。碱性条件有利于碘代酚类 DBPs 的形成，而酸性条件有利于碘代醌 DBPs 的生成。中性条件可能是控制碘代芳香族 DBPs 形成的最适宜 pH 条件。几乎所有碘代芳香族 DBPs 的相对浓度随时间先增加后减少，表明在氯化过程中，碘代芳香族 DBPs 可能进一步转化为卤代脂肪族 DBPs。这项研究为水中苯酚的去除提供了研究基础。
