Formation of halonitromethanes from methylamine in the presence of bromide during UV/Cl2 disinfection  

作　　者：Lin Deng Wei Luo Xiao Chi Tingting Huang Longjia Wen Huiyu Dong Mingxian Wu Jun Hu 

机构地区：[1]Department of Municipal Engineering,Southeast University,Nanjing 211189,China [2]Zhejiang Haihe Environmental Technology Co.,Ltd.,Jinhua 321000,China [3]Research Center for Eco-Environmental Sciences,University of Chinese Academy of Sciences,Chinese Academy of Sciences,Beijing 100085,China [4]Zhejiang Truelove Blanket Technology Co.,Ltd.,Jinhua 322000,China [5]College of Environment,Zhejiang University of Technology,Hangzhou 310014,China

出　　处：《Journal of Environmental Sciences》2022年第7期28-36,共9页环境科学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 22076023 , 21677032 and 51808496)。

摘　　要：The UV/Clprocess is commonly used to achieve a multiple-barrier disinfection and maintain residuals. The study chose methylamine as a precursor to study the formation of hightoxic halonitromethanes(HNMs) in the presence of bromide ions(Br-) during UV/Cldisinfection. The maximum yield of HNMs increased first and then decreased with increasing concentration of Br-. An excessively high concentration of Br-induced the maximum yield of HNMs in advance. The maximum bromine incorporation factor(BIF) increased, while the maximum bromine utilization factor(BUF) decreased with the increase of Br-concentration. The maximum yield of HNMs decreased as p H value increased from 6.0 to 8.0 due to the deprotonation process. The BUF value remained relatively higher under an acidic condition, while p H value had no evident influence on the BIF value. The maximum yield of HNMs and value of BUF maximized at a Cl:Br-ratio of 12.5, whereas the BIF value remained relatively higher at low Cl:Br-ratios(2.5 and 5). The amino group in methylamine was first halogenated, and then released into solution as inorganic nitrogen by the rupture of C-N bond or transformed to nitro group by oxidation and elimination pathways. The maximum yield of HNMs in real waters was higher than that in pure water due to the high content of dissolved organic carbon. Two real waters were sampled to verify the law of HNMs formation. This study helps to understand the HNMs formation(especially brominated species) when the UV/Clprocess is adopted as a disinfection technique.

关 键 词：HNMs UV/Cl2 process METHYLAMINE BROMIDE 

分 类 号：TU991.2[建筑科学—市政工程]