文献类型：期刊文献

英文题名：Reactivity of Brcl, Br2O, Br2, and Hobr Toward Polyamide Nanofiltration Membranes

作者：Zhao, Huihui[1,2]; Yang, Linyan[5]; Chen, Xueming[3]; Bai, Lichun[4]; Cao, Guomin[1,2]; Cai, Lankun[1,2]; Tang, Chuyang Y.[5]

机构：[1] National Engineering Laboratory for Industrial Wastewater Treatment, East China University of Science and Technology, Shanghai, 200237, China; [2] School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China; [3] Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Resources, Fuzhou University, Fujian, Fuzhou, 350116, China; [4] Key Laboratory of Traffic Safety on Track [Central South University], Ministry of Education, School of Traffic & Transportation Engineering, Central South University, Changsha, 410075, China; [5] Department of Civil Engineering, University of Hong Kong, Pokfulam, Hong Kong

年份：2022

外文期刊名：SSRN

收录：EI(收录号：20220303114)

语种：英文

外文关键词：Bromine compounds - Nanofiltration - Nanofiltration membranes - Osmosis membranes - Rate constants - Reverse osmosis

摘要：Polyamide (PA) membranes, widely used for reverse osmosis and nanofiltration, are prone to bromination under chlorinated bromide-containing water conditions. Conventional wisdom generally assumes HOBr as the only active brominating agent responsible for PA membrane degradation, while some more reactive but less abundant brominating agents (including Br2O, BrOCl, BrCl and Br2) are often overlooked. The current study addresses this critical literature gap by systematically evaluating membrane degradation under various [Br?], [Cl?] and [HOCl]. The observed pseudo-first-order rate constant of membrane degradation (kobsm , using change in water flux as a surrogate indicator) was found to be well correlated to [Br?], [Cl?] and [HOCl] (R2>0.90). The gradual increase of [Cl?] and [Br?] transforms the predominant brominating agent from HOBr to BrCl and Br2, respectively, under excessive [Br?] conditions. The species-specific second-order reaction rate constants followed a decreasing order of kBrClm (2.6×104 M?1·s?1) > kBrOClm (2.0×103 M?1·s?1) > kBrm2O (9.6×102 M?1·s?1) > kBrm2 (1.5×101 M?1·s?1) > kHOBrm (5.4×10?1 M?1·s?1). Additional decay tests using benzanilide (BA) as a surrogate monomer compound confirmed BrCl as the most reactive species. Under typical seawater conditions (pH 8.0), the more reactive but less abundant BrCl had significantly greater contribution to membrane degradation (85%) than HOBr (3%). Under typical neutral wastewater conditions, both BrCl and HOBr contributed equally. This study provides novel and fundamental insights to assess and prevent membrane degradation. ? 2022, The Authors. All rights reserved.