Liang Jun-Kun, Lu Yao, Song Zhi-Min, Ye Bei, Wu Qian-Yuan, Hu Hong-Ying
State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China.
State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua-Berkeley Shenzhen Institute, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China; Environmental Simulation and Pollution Control State Key Joint Laboratory, Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China.
Sci Total Environ. 2022 Jun 10;824:153739. doi: 10.1016/j.scitotenv.2022.153739. Epub 2022 Feb 8.
During chlorination of reclaimed water, the dose of chlorine used can influence the formation of chlorinated disinfection by-products (Cl-DBPs). We used non-targeted screening by Orbitrap mass spectrometry to identify Cl-DBPs in samples of chlorinated reclaimed water, and found that chlorination was likely to form slightly oxidized unsaturated aliphatic compounds and polycyclic aromatic compounds. Increasing the chlorine dose increased the proportion of polycyclic aromatic Cl-DBPs containing one chlorine atom (Cl-DBPs) and highly oxidized unsaturated aliphatic Cl-DBPs containing two chlorine atoms (Cl-DBPs). In addition, increasing the chlorine dose first decreased and then increased the proportion of Cl-DBPs with aromatic index values >0.5 and increased the proportion of Cl-DBPs with aromatic index values <0.5. Increasing the chlorine dose increased double bond equivalent minus oxygen values of Cl-DBPs and decreased the double bond equivalent minus oxygen values of Cl-DBPs, while the nominal oxidant state of carbon decreased for Cl-DBPs and increased for Cl-DBPs. In considering the possible precursors of Cl-DBPs and their reaction pathways, substitution reactions occurred more readily with aliphatic compounds and addition reactions occurred more readily with aromatic precursors. When the chlorine dose is increased, more Cl-DBPs may be formed by substitution. Overall, the chlorine dose influences Cl-DBP formation and composition and should be taken into account during water treatment.
在再生水氯化过程中，所使用的氯剂量会影响氯代消毒副产物（Cl-DBPs）的形成。我们使用轨道阱质谱进行非靶向筛查，以鉴定氯化再生水样品中的Cl-DBPs，发现氯化过程可能会形成轻度氧化的不饱和脂肪族化合物和多环芳烃化合物。增加氯剂量会增加含一个氯原子的多环芳烃Cl-DBPs（Cl-DBPs）和含两个氯原子的高度氧化不饱和脂肪族Cl-DBPs（Cl-DBPs）的比例。此外，增加氯剂量首先会降低然后增加芳香指数值>0.5的Cl-DBPs的比例，并增加芳香指数值<0.5的Cl-DBPs的比例。增加氯剂量会增加Cl-DBPs的双键当量减氧值，并降低Cl-DBPs的双键当量减氧值，而Cl-DBPs的碳的标称氧化态降低，Cl-DBPs的碳的标称氧化态增加。在考虑Cl-DBPs的可能前体及其反应途径时，取代反应更容易与脂肪族化合物发生，加成反应更容易与芳香族前体发生。当增加氯剂量时，更多的Cl-DBPs可能通过取代形成。总体而言，氯剂量会影响Cl-DBP的形成和组成，在水处理过程中应予以考虑。
