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Guo Y, Xu J, Bai X, Lin Y, Zhou W, Li J. Free chlorine formation in the process of the chlorine dioxide oxidation of aliphatic amines. WATER RESEARCH 2022; 217:118399. [PMID: 35427831 DOI: 10.1016/j.watres.2022.118399] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/25/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
Chlorine dioxide (ClO2) is commonly used as an alternative disinfectant to chlorine because it has a high bactericidal effect and may produce limited concentrations of halogenated disinfection byproducts (DBPs). However, previous studies have reported that free available chlorine (FAC) was produced when ClO2 reacted with some compounds, such as phenol, leading to the formation of halogenated DBPs. In this study aliphatic amines was found to react rapidly with ClO2 to form significant amount of FAC and its related DBPs. This study investigated the formation of FAC when ClO2 reacts with six model aliphatic amines (including primary amines, secondary amines and tertiary amines). FAC was formed immediately as ClO2 was added to the precursor solution. The maximum yield of FAC even reached 45% (based on consumed ClO2) when ClO2 reacted with 20 μM methylamine at a dose of 10 μM, which is close to a realistic maximum dose (about 0.8 mg/L) in the U.S.. The reactivity of amines to result FAC follows the sequence tertiary amines < secondary amines < primary amines. It was verified that the addition of aliphatic amines may enhance the formation of FAC during ClO2 oxidation in actual water samples. Organic chloramines and other chlorinated DBPs, such as cyanogen chloride, were detected when ClO2 was used as the sole oxidant of real water samples. This study demonstrated that chlorine-related byproducts may also be formed in the presence of organic amines during ClO2 treatment.
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Affiliation(s)
- Yang Guo
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China
| | - Jie Xu
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China
| | - Xueling Bai
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China
| | - Yan Lin
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China
| | - Wenfeng Zhou
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China.
| | - Jing Li
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan Xilu No.2, Beijing 100193, China.
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2
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Shen L, Chen Z, Kang J, Yan P, Shen J, Wang B, Zhao S, Bi L, Wang S, Cheng Y. N-nitrosodimethylamine formation during oxidation of N,N-dimethylhydrazine compounds by peroxymonosulfate: Kinetics, reactive species, mechanism and influencing factors. JOURNAL OF HAZARDOUS MATERIALS 2022; 428:128191. [PMID: 35033910 DOI: 10.1016/j.jhazmat.2021.128191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/05/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
This study found that peroxymonosulfate (PMS) oxidation without activation has the potential to generate a suspected human carcinogen, N-nitrosodimethylamine (NDMA), in water containing N,N-dimethylhydrazine compounds. Considerable amounts of NDMA formed from three compounds by PMS oxidation were observed. 1,1,1',1'-Tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS), which is an industrial antiyellowing agent and light stabilizer, was used as a representative to elucidate the kinetics, transformation products, mechanism and NDMA formation pathways of PMS oxidation. TMDS degradation and NDMA formation involved direct PMS oxidation and singlet oxygen (1O2) oxidation. The oxidation by PMS/1O2 was pH-dependent, which was related to the pH-dependent characteristics of the reactive oxygen species and intermediates. The degradation mechanism of TMDS mainly included the side chain cleavage, dealkylation, and O-addition. NDMA was generated from TMDS mainly via O-addition and 1,1-dimethylhydrazine (UDMH) generation. The cleavage of amide nitrogen in O-addition products and primary amine nitrogen in UDMH are likely the key steps in NDMA generation. The results emphasized that the formation of harmful by-products should be taken into account when assessing the feasibility of PMS oxidation.
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Affiliation(s)
- Linlu Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jing Kang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Pengwei Yan
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Binyuan Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Shengxin Zhao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Lanbo Bi
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Shuyu Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Yizhen Cheng
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
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Wu Y, Zhang W, Bu L, Zhu S, Wang J, Zhou S. UV-induced activation of organic chloramine: Radicals generation, transformation pathway and DBP formation. JOURNAL OF HAZARDOUS MATERIALS 2022; 421:126459. [PMID: 34365233 DOI: 10.1016/j.jhazmat.2021.126459] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/03/2021] [Accepted: 06/21/2021] [Indexed: 06/13/2023]
Abstract
Organic chloramines of little disinfection efficacy commonly exist in disinfection process (chlor(am)ination) due to the wide presence of organic amines in water, of which N-chlorodimethylamine (CDMA) is a typical one. For the first time, UV photolysis for the activation of CDMA was investigated. UV photolysis caused the cleavage of N-Cl bond in CDMA to form Cl• and subsequently HO•, both of which are dominant contributors to the destruction of model contaminant bisphenol A (BPA). Typical spectra of HO• were detected by electron paramagnetic resonance (EPR) experiments, while spectra of reactive nitrogen species (RNS) were not detected during UV photolysis of CDMA. The increase of pH (6.0-8.0), HCO3-/CO32-, Cl- and nature organic matter inhibited the degradation of BPA. We proposed pathways of CDMA and BPA degradation based on the identified transformation products. UV photolysis of CDMA and BPA reduced the formation of N-nitrosodimethylamine (NDMA) at pH 8.0, but increased the formation of trichloronitromethane (TCNM) at pH 7.0 and 8.0. The increasing toxicity and the formation of TCNM and NDMA gave us a hint that formation of organic chloramines should be concerned.
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Affiliation(s)
- Yangtao Wu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Weiqiu Zhang
- School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Lingjun Bu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Shumin Zhu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China.
| | - Jue Wang
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Shiqing Zhou
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China
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Sun C, Wang R, Wang T, Li Q. Primary evaluation of nine volatile N-nitrosamines in raw red meat from Tianjin, China, by HS-SPME-GC–MS. Food Chem 2020; 310:125945. [DOI: 10.1016/j.foodchem.2019.125945] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/17/2019] [Accepted: 11/21/2019] [Indexed: 01/08/2023]
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Wang X, Zhou B, Shao X. Determination of acid dissociation constants and reaction kinetics of dimethylamine-based PPCPs with O 3, NaClO, ClO 2 and KMnO 4. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2019; 54:518-525. [PMID: 30789068 DOI: 10.1080/10934529.2019.1567183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 01/03/2019] [Accepted: 01/05/2019] [Indexed: 06/09/2023]
Abstract
Dimethylamine-based pharmaceutical personal care products (DMA-based PPCPs) are a group of N-nitrosodimethylamine (NDMA) precursors. The acid dissociation constant (pKa) values of four DMA-based PPCPs were determined by potentiometric titration over the pH range of 3-11. The pKa values of ranitidine, nizatidine, doxylamine and carbinoxamine corresponding to the DMA moiety were 8.4, 6.8, 9.4 and 9.1, respectively. Competition reaction kinetics and pseudo-first-order reaction kinetics were used to determine the reaction rate constant (k) of the DMA-based PPCPs with O3, NaClO, ClO2 and KMnO4. Comparing the degradation rate constants of the four DMA-based PPCPs, the results of ClO2 oxidation were close, and for the other three oxidants, the order was kranitidine ≈ knizatidine > kdoxylamine ≈ kcarbinoxamine. Comparing the reaction rate of the four oxidants, for ranitidine and nizatidine, the order was kNaClO > kO3 > kKMnO4 > kClO2, and for doxylamine and carbinoxamine, the order was kO3 > kNaClO > kClO2 > kKMnO4.
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Affiliation(s)
- Xiaofeng Wang
- a School of Energy and Environmental Engineering , University of Science & Technology Beijing , Beijing , China
| | - Beihai Zhou
- a School of Energy and Environmental Engineering , University of Science & Technology Beijing , Beijing , China
| | - Xia Shao
- b Beijing Municipal Research Institute of Environmental Protection , Beijing , China
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Wang X, Yang H, Zhou B, Wang X, Xie Y. Effect of oxidation on amine-based pharmaceutical degradation and N-Nitrosodimethylamine formation. WATER RESEARCH 2015; 87:403-11. [PMID: 26469132 DOI: 10.1016/j.watres.2015.07.045] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Revised: 07/24/2015] [Accepted: 07/27/2015] [Indexed: 05/09/2023]
Abstract
Four pharmaceuticals (ranitidine, nizatidine, doxylamine, and carbinoxamine) were selected as model compounds to assess the efficiency of four oxidants (ozone (O3), chlorine (Cl2), chlorine dioxide (ClO2) and potassium permanganate (KMnO4)) on the removal of amine-based pharmaceutical and personal care products (PPCPs), as well as the reduction of their N-Nitrosodimethylamine formation potentials (NDMAFPs). The changes in PPCPs and their NDMAFPs during oxidation were quantified using various oxidants and dosages. The relationship between oxidation product structures and NDMAFP changes was also analyzed. The results showed that oxidation with O3, Cl2 and ClO2 were effective in removing the selected PPCPs. However, only ozonation was effective in reducing their NDMAFPs. Ozonation at 6 mg/L removed approximately 90% PPCPs and 90% NDMAFPs for all PPCPs. In addition, the results indicated that ozonation products made little contribution to NDMAFPs. In contrast, some PPCP products had higher NDMAFPs than PPCPs after oxidation with Cl2, ClO2 and KMnO4. There were two possible reaction pathways that led to decrease in NDMAFPs after oxidation. One was oxygen transfer to nitrogen at the tertiary amine site and the other was N-dealkylation from the tertiary amine site.
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Affiliation(s)
- Xiaofeng Wang
- Department of Environmental Engineering, School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Hongwei Yang
- School of Environment, Tsinghua University, Beijing 100084, China.
| | - Beihai Zhou
- Department of Environmental Engineering, School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Xiaomao Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yuefeng Xie
- School of Environment, Tsinghua University, Beijing 100084, China; Civil and Environmental Engineering Programs, Pennsylvania State University, Middletown, PA 17057, USA
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7
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The Influence of Phosphate Buffer on the Formation of N-Nitrosodimethylamine from Dimethylamine Nitrosation. J CHEM-NY 2013. [DOI: 10.1155/2013/818943] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Buffer solutions were widely used for almost all the investigations concerning N-nitrosodimethylamine (NDMA), a member of powerful mutagenic and carcinogenic compounds which are ubiquitous in the environment. However, whether or how the buffer matrixes influence NDMA formation is still unknown. The effect of buffer solutions on NDMA formation from the nitrosation of dimethylamine (DMA) by nitrite (NaNO2) was investigated at pH 6.4 in four kinds of buffer solutions, that is, Na2HPO4/C6H8O7, Na3(C6H5O7)/C6H8O7, NaH2PO4/NaOH, and NaH2PO4/Na2HPO4. Our observations demonstrate an unexpected inhibitory effect of the buffer solutions on NDMA formation and the phosphate buffer plays a more significant role in inhibiting NDMA formation compared to the citrate buffer. Moreover, the amount of the phosphate in the buffer was also found to greatly impact the formation of NDMA. A further investigation indicates that it is the interaction between NaH2PO4and reactant NaNO2rather than DMA that leads to the inhibitory effect of phosphate buffer during the DMA nitrosation reaction. This study expands the understanding of the influence of buffer solution on nitrosamines formation through the nitrosation pathway and further gives a hint for water plants to reduce the formation of nitrosamines.
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Fujioka T, Khan SJ, Poussade Y, Drewes JE, Nghiem LD. N-nitrosamine removal by reverse osmosis for indirect potable water reuse – A critical review based on observations from laboratory-, pilot- and full-scale studies. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2012.07.025] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Andrzejewski P, Fijolek L, Nawrocki J. An influence of hypothetical products of dimethylamine ozonation on N-nitrosodimethylamine formation. JOURNAL OF HAZARDOUS MATERIALS 2012; 229-230:340-345. [PMID: 22770583 DOI: 10.1016/j.jhazmat.2012.06.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 06/01/2012] [Accepted: 06/07/2012] [Indexed: 06/01/2023]
Abstract
The paper concerns formation of N-nitrosodimethylamine (NDMA) upon ozonation of dimethylamine (DMA) aqueous solutions. According to current hypothesis ozonated DMA is oxidized to N-dimethylhydroxylamine (DMHA), then to N-methylhydroxylamine (MHA) and finally to hydroxylamine (HA). HA subsequently reacts with the remain part of DMA to form unsymmetrical dimethylhydrazine (UDMH). Finally UDMH undergoes oxidation with ozone to form NDMA. HA is thought to be an important by-product that increases the NDMA formation. We decided to verify the hypothesis by an ozonation of DMA aqueous solutions in the presence of DMHA, MHA and HA. We have clearly proved that ozonation of DMA in the presence of DMHA and/or MHA does not increase NDMA formation. These results do not exclude the possibility of HA formation during DMA ozonation, but unambiguously show that even if HA is formed during this reaction, it does not have any impact on NDMA formation. In authors opinion the formation of MHA and HA is however doubtful since both compounds seem to be rather products of reduction than oxidation. Therefore HA-DMA reaction cannot be responsible for the formation of NDMA when DMA aqueous solution is ozonized.
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Affiliation(s)
- P Andrzejewski
- Adam Mickiewicz University, Faculty of Chemistry, Department of Water Treatment Technology, ul. Drzymały 24, 60-613 Poznań, Poland.
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Sharma VK. Kinetics and mechanism of formation and destruction of N-nitrosodimethylamine in water – A review. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2011.11.028] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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11
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Sun Z, Liu YD, Zhong RG. Carbon Dioxide in the Nitrosation of Amine: Catalyst or Inhibitor? J Phys Chem A 2011; 115:7753-64. [DOI: 10.1021/jp202002m] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Zhi Sun
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100124, People's Republic of China
| | - Yong Dong Liu
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100124, People's Republic of China
| | - Ru Gang Zhong
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100124, People's Republic of China
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Nawrocki J, Andrzejewski P. Nitrosamines and water. JOURNAL OF HAZARDOUS MATERIALS 2011; 189:1-18. [PMID: 21353742 DOI: 10.1016/j.jhazmat.2011.02.005] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 01/17/2011] [Accepted: 02/03/2011] [Indexed: 05/30/2023]
Abstract
This paper provides an overview of all current issues that are connected to the presence of nitrosamines in water technology. N-nitrosodimethylamine (NDMA) is the most frequently detected member of this family. Nitrosamines became the hottest topic in drinking water science when they were identified as disinfection by-products (DBPs) in chloraminated waters. The danger that they pose to consumer health seems to be much higher than that from chlorinated DBPs. This review summarizes our contemporary knowledge of these compounds in water, their occurrence, and precursors of nitrosamines in drinking and wastewaters, in addition to attempts to remove nitrosamines from water. The paper also reviews our knowledge of the mechanisms of nitrosamine formation in water technology. The current, commonly accepted mechanism of NDMA formation during chloramination of drinking waters assumes that dichloramine reacts with dimethylamine, forms unsymmetrical dimethylhydrazine and further oxidizes to NDMA. The question to answer is which precursors are responsible for delivering the DMA moiety for the reaction since the presence of DMA in water cannot explain the quantities of NDMA that are formed. There are also reports that other oxidants that are commonly used in water technology may generate NDMA. However, the mechanisms of such transformations are unknown. Methods for the removal of nitrosamines from water are described briefly. However, the research that has been undertaken on such methods seems to be at an early stage of development. It is predicted that photolytic methods may have the greatest potential for technological application.
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Affiliation(s)
- Jacek Nawrocki
- Laboratory of Water Treatment Technology, Faculty of Chemistry, A Mickiewicz University, Poznań, Poland.
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Xiao F. Comment on "Inhibiting the regeneration of N-nitrosodimethylamine in drinking water by UV photolysis combined with ozonation" by B. Xu, Z. Chen, F. Qi, J. Ma, F. Wu [J. Hazard. Mater. 168 (2009) 108-114]. JOURNAL OF HAZARDOUS MATERIALS 2009; 172:518-519. [PMID: 19640642 DOI: 10.1016/j.jhazmat.2009.06.164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 06/28/2009] [Accepted: 06/30/2009] [Indexed: 05/28/2023]
Affiliation(s)
- Feng Xiao
- Room 3575, Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong.
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Yang L, Chen Z, Shen J, Xu Z, Liang H, Tian J, Ben Y, Zhai X, Shi W, Li G. Reinvestigation of the nitrosamine-formation mechanism during ozonation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:5481-5487. [PMID: 19708385 DOI: 10.1021/es900319f] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Previous studies have linked nitrosamine formation during ozonation to a nitrosation process in which nitrosation is catalyzed by formaldehyde, a normal byproduct of ozonation. This mechanism cannot explain the increase in N-nitrosodimethylamine (NDMA) formation with an increase of pH. This study reinvestigates the pathway of N-nitrosamine formation during ozonation. Our observations demonstrated the critical importance of some reactive inorganic nitrogenous intermediates, such as hydroxylamine and dinitrogen tetroxide (N2O4). We report two altemative pathways that possibly explain nitrosamine formation during ozonation at neutral and alkaline pH: (i) secondary amine precursors reacting with hydroxylamine to form unsymmetrical dialkylhydrazine intermediates, which are further oxidized to their relevant nitrosamines; and (ii) a nitrosation pathway in which N2O4 acts as the nitrosating reagent. The key variables of pathway (i) (including reaction time, pH, dissolved oxygen) were investigated. Since hydroxylamine is a common intermediate of dimethylamine oxidation, it is reasonable to assume that hydroxylamine is a possible inorganic precursor for NDMA formation during oxidation processes using strong oxidants. With an improved understanding of the pathway of nitrosamine formation, it should be apparent that the reactive nitrogenous intermediates play an important role in the N-nitrosamine-formation, so future studies of N-nitrosamine-formation control should be focused on the transformation of nitrogen in water treatment
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Affiliation(s)
- Lei Yang
- State Key Laboratory of Urban Water Resources and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China
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