文献类型：期刊文献

英文题名：Unraveling the dominant chlorination mechanism of polyamide membranes: N-chlorination of the iminol form assisted by water clusters

作者：Wu, Yi[1];Wu, Shuang[2];Yu, Qinyu[1];Yang, Linyan[1,3,4];Zhen, Huajun[1];Bai, Lichun[2];Tang, Chuyang Y.[5]

机构：[1]East China Univ Sci & Technol, Sch Resources & Environm Engn, Shanghai 200237, Peoples R China;[2]Cent South Univ, Sch Traff & Transportat Engn, Key Lab Traff Safety Track, Minist Educ, Changsha 410075, Peoples R China;[3]Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China;[4]East China Univ Sci & Technol, Natl Engn Res Ctr Ind Wastewater Detoxicat & Resou, Shanghai 200237, Peoples R China;[5]Univ Hong Kong, Dept Civil Engn, Pokfulam, Hong Kong 999077, Peoples R China

年份：2026

卷号：532

外文期刊名：CHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20260920159712);WOS:【SCI-EXPANDED(收录号:WOS:001706749400001)】；

基金：This study was sponsored by the National Natural Science Foundation of China (52100085) .

语种：英文

外文关键词：Polyamide membranes; Benzanilide; Chlorination; DFT simulation

摘要：Polyamide membranes are widely used in water treatment but highly susceptible to chlorination, leading to performance failure. This study combined density functional theory (DFT) simulations with experimental analyses to elucidate the dominant chlorination mechanism. DFT revealed three potential pathways, namely Ochlorination of the amide form (223.73 kJ/mol), N-chlorination of the amide form (275.34 kJ/mol) and Nchlorination of the iminol form (118.36 kJ/mol). The iminol pathway was the most favorable, with its barrier further reduced to 98.28 kJ/mol by a tetrahedral water cluster, elucidating the quantitative role of water clusters as proton-shuttle catalysts for chlorination process. This mechanism involves the conversion of-C(O)NH-to-C (OH) = Nvia Grotthuss-type proton transfer, followed by chlorine attack to the iminol nitrogen to form an N-Cl bond. XPS and FTIR results validated the transformation between C=O and C-OH, and showed 87.5% and 45.1% of chlorine covalently incorporated into the membrane and benzanilide (BA), respectively. LC-MS confirmed N-H to N-Cl conversion by a consistent +34 Da mass shift. The reaction rate constants obtained from simulations (1.69 & times; 10-2 M-1 s-1) and experiments (2.76 & times; 10-2 M-1 s-1) at 298.15 K and 1 atm were in close agreement, which are positively dependent on temperature (r = 0.85-0.87). This work provides atomic-level insights into polyamide chlorination, establishing a foundation for designing chlorine-resistant membranes.