Kinetic and mechanistic aspects of selenite oxidation by chlorine, bromine, monochloramine, ozone, permanganate, and hydrogen peroxide

CORC > 生态环境研究中心 > 中国科学院生态环境研究中心 > 中国科学院饮用水科学与技术重点实验室

	Kinetic and mechanistic aspects of selenite oxidation by chlorine, bromine, monochloramine, ozone, permanganate, and hydrogen peroxide
	Liu, Shaogang ; Salhi, Elisabeth ; Huang, Wanting ; Diao, Kaisheng ; von Gunten, Urs
刊名	WATER RESEARCH
	2019-11-01
卷号	164 页码:-
关键词	Selenium Chemical oxidation Bromide Oxidation mechanisms Kinetic modeling Arsenic Sulfite
ISSN号	0043-1354
英文摘要	Selenium (mainly in the forms of selenite (Se(IV)) and selenate (Se(VI)) is a regulated drinking water contaminant, but there is little information on the kinetics and mechanisms of Se(IV) oxidation during water treatment. Species-specific and apparent second-order rate constants for the oxidation of Se(IV) at pH 7.0 were determined in buffered solutions and they decrease in the order bromine (5.8 0.3 x 103 M-1 s(-1)) > ozone (03, 513.4 10.0 M-1 s(-1)) > chlorine (61.0 3.6 M-1 s(-1)) > permanganate (2.1 0.1 M-1 s(-1)), monochloramine (NH2CI, (1.3 0.1) x 10-3 M-1 s(-1)), and hydrogen peroxide (H202, (2.3 0.1) x 10-5 M-1 s(-1)). The reaction stoichiometries for the reactions of Se(IV) with bromine, 03, chlorine, NH2CI, and H202 are 1:1. For Mn(Vll), the stoichiometries varied with pH and were 5:2, 3:2, and 1:2 for acidic, neutral, and alkaline conditions, respectively. Based on the reaction orders and stoichiometries, the corresponding Se(IV) oxidation mechanisms for various oxidants are discussed. The role of bromide for Se(IV) oxidation was also investigated during chlorination and ozonation of Se(IV)containing water. During chlorination, bromide-catalysis enhances the rate of the oxidation of Se(IV) to Se(VI) from 50% to nearly 90% with bromide concentrations of 50 pig L-1 and 200 pig L-1, respectively, at pH 7.0 and a chlorine dose of 2.0 mg L-1 (within 15 min). During ozonation, bromide had no effect on Se(IV) oxidation. Based on the determined second order rate constants, the oxidation of Se(IV) by chlorine and ozone were successfully predicted in a natural water by a kinetic model. The second order rate constants for the same oxidants were also investigated and/or evaluated for other related anions, such as arsenite (As(III)) and sulfite (S(IV)). They decreased in the order S(IV)> As(III)> Se(IV). (C) 2019 Elsevier Ltd. All rights reserved.
内容类型	期刊论文
源URL	[http://ir.rcees.ac.cn/handle/311016/43483]
专题	生态环境研究中心_中国科学院饮用水科学与技术重点实验室
作者单位	1.Univ Chinese Acad Sci, Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Key Lab Drinking Water Sci & Technol, 18 Shuang Qing Rd, Beijing 100085, Peoples R China 2.Guangxi Univ Nationalities, Sch Chem & Chem Engn, Guangxi Key Lab Chem & Engn Forest Prod, Nanning 530008, Guangxi, Peoples R China 3.Eawag, Swiss Fed Inst Aquat Sci & Technol, Uberlandstr 133, CH-8600 Dubendorf, Switzerland
推荐引用方式 GB/T 7714	Liu, Shaogang,Salhi, Elisabeth,Huang, Wanting,et al. Kinetic and mechanistic aspects of selenite oxidation by chlorine, bromine, monochloramine, ozone, permanganate, and hydrogen peroxide[J]. WATER RESEARCH,2019,164:-.
APA	Liu, Shaogang,Salhi, Elisabeth,Huang, Wanting,Diao, Kaisheng,&von Gunten, Urs.(2019).Kinetic and mechanistic aspects of selenite oxidation by chlorine, bromine, monochloramine, ozone, permanganate, and hydrogen peroxide.WATER RESEARCH,164,-.
MLA	Liu, Shaogang,et al."Kinetic and mechanistic aspects of selenite oxidation by chlorine, bromine, monochloramine, ozone, permanganate, and hydrogen peroxide".WATER RESEARCH 164(2019):-.