1
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Fedorov K, Kong L, Wang C, Boczkaj G. High-performance activation of ozone by sonocavitation for BTEX degradation in water. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 363:121343. [PMID: 38843727 DOI: 10.1016/j.jenvman.2024.121343] [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: 02/27/2024] [Revised: 05/10/2024] [Accepted: 05/30/2024] [Indexed: 06/18/2024]
Abstract
This work presents a novel advanced oxidation process (AOP) for degradation of emerging organic pollutants - benzene, toluene, ethylbenzene and xylenes (BTEXs) in water. A comparative study was performed for sonocavitation assisted ozonation under 40-120 kHz and 80-200 kHz dual frequency ultrasounds (DFUS). Based on the obtained results, the combination of 40-120 kHz i.e., low-frequency US (LFDUS) with O3 exhibited excellent oxidation capacity degrading 99.37-99.69% of BTEXs in 40 min, while 86.09-91.76% of BTEX degradation was achieved after 60 min in 80-200 kHz i.e., high-frequency US (HFDUS) combined with O3. The synergistic indexes determined using degradation rate constants were found as 7.86 and 2.9 for LFDUS/O3 and HFDUS/O3 processes, respectively. The higher extend of BTEX degradation in both processes was observed at pH 6.5 and 10. Among the reactive oxygen species (ROSs), hydroxyl radicals (HO•) were found predominant according to scavenging tests, singlet oxygen also importantly contributed in degradation, while O2•- radicals had a minor contribution. Sulfate (SO42-) ions demonstrated higher inhibitory effect compared to chloride (Cl-) and carbonate (CO32-) ions in both processes. Degradation pathways of BTEX was proposed based on the intermediates identified using GC-MS technique.
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Affiliation(s)
- Kirill Fedorov
- Gdansk University of Technology, Faculty of Civil and Environmental Engineering, Department of Sanitary Engineering, Gdansk, Poland
| | - Lingshuai Kong
- Institute of Eco-Environmental Forensics, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Chongqing Wang
- School of Chemical Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Grzegorz Boczkaj
- Gdansk University of Technology, Faculty of Civil and Environmental Engineering, Department of Sanitary Engineering, Gdansk, Poland; Gdansk University of Technology, EcoTech Center, 11/12 Narutowicza St., 80-233, Gdansk, Poland.
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2
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Kung WM, Lin HHH, Wang YH, Lin AYC. Solar-driven persulfate degradation of caffeine and cephradine in synthetic human urine. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133031. [PMID: 38008053 DOI: 10.1016/j.jhazmat.2023.133031] [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: 08/08/2023] [Revised: 11/08/2023] [Accepted: 11/16/2023] [Indexed: 11/28/2023]
Abstract
Urine source separation, as an innovative concept for the reuse of microlevel nutrients in human urine, has drawn increasing attention recently. Consequently, removing coexisting pharmaceuticals in urine is necessary for further reuse. This study is the first to apply the solar-driven persulfate process (Solar/PS) to the investigation of cephradine (CFD) and caffeine (CAF) degradation in synthetic human urine. The results showed that significantly more degradation of CFD and CAF occurs with the Solar/PS process than with persulfate oxidation and direct sunlight photolysis, respectively. The generated reactive species ·OH, SO4·-, O2·- and 1O2 were identified in the Solar/PS process. While SO4·- played a dominant role at pH 6, it played a minor role at pH 9 due to the lower amount generated under alkaline conditions. The presence of chloride and ammonia negatively impacted the photodegradation of both compounds. In contrast, bicarbonate exhibited no effect on CAF but enhanced CFD degradation owing to its amino-acid-like structure, which has a higher reactivity toward CO3·-. Although total organic carbon (TOC) was partially mineralized after 6 h of operation, no Microtox® toxicity was observed.
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Affiliation(s)
- Wei-Ming Kung
- Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC
| | - Hank Hui-Hsiang Lin
- Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC
| | - Yu-Hsiang Wang
- Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC
| | - Angela Yu-Chen Lin
- Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC.
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3
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Jones SH, King MD, Rennie AR, Ward AD, Campbell RA, Hughes AV. Aqueous Radical Initiated Oxidation of an Organic Monolayer at the Air-Water Interface as a Proxy for Thin Films on Atmospheric Aerosol Studied with Neutron Reflectometry. J Phys Chem A 2023; 127:8922-8934. [PMID: 37830513 PMCID: PMC10614302 DOI: 10.1021/acs.jpca.3c03846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 09/12/2023] [Indexed: 10/14/2023]
Abstract
Neutron reflectometry has been used to study the radical initiated oxidation of a monolayer of the lipid 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) at the air-solution interface by aqueous-phase hydroxyl, sulfate, and nitrate radicals. The oxidation of organic films at the surface of atmospheric aqueous aerosols can influence the optical properties of the aerosol and consequently can impact Earth's radiative balance and contribute to modern climate change. The amount of material at the air-solution interface was found to decrease on exposure to aqueous-phase radicals which was consistent with a multistep degradation mechanism, i.e., the products of reaction of the DSPC film with aqueous radicals were also surface active. The multistep degradation mechanism suggests that lipid molecules in the thin film degrade to form progressively shorter chain surface active products and several reactive steps are required to remove the film from the air-solution interface. Bimolecular rate constants for oxidation via the aqueous phase OH radical cluster around 1010 dm3 mol-1 s-1. Calculations to determine the film lifetime indicate that it will take ∼4-5 days for the film to degrade to 50% of its initial amount in the atmosphere, and therefore attack by aqueous radicals on organic films could be atmospherically important relative to typical atmospheric aerosol lifetimes.
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Affiliation(s)
- Stephanie H. Jones
- Centre
of Climate, Ocean and Atmosphere, Department of Earth Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, U.K.
- STFC,
Central Laser Facility, Research Complex
at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0FA, U.K.
| | - Martin D. King
- Centre
of Climate, Ocean and Atmosphere, Department of Earth Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, U.K.
| | - Adrian R. Rennie
- Department
of Chemistry, Angström Laboratory, Uppsala University, 75121 Uppsala, Sweden
| | - Andrew D. Ward
- STFC,
Central Laser Facility, Research Complex
at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0FA, U.K.
| | - Richard A. Campbell
- Institut
Laue-Langevin, BP 156, 6, 71 avenue des Martyrs, CS 20156, F-38042
Cedex 9 Grenoble, France
| | - Arwel V. Hughes
- ISIS
Pulsed Neutron and Muon source, Rutherford
Appleton Laboratory, Harwell Oxford, Oxfordshire OX11 0QX, U.K.
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4
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Chu C, Yan Y, Ma J, Jin S, Spinney R, Dionysiou DD, Zhang H, Xiao R. Implementation of laser flash photolysis for radical-induced reactions and environmental implications. WATER RESEARCH 2023; 244:120526. [PMID: 37672949 DOI: 10.1016/j.watres.2023.120526] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/06/2023] [Accepted: 08/24/2023] [Indexed: 09/08/2023]
Abstract
Confronted with the imperative crisis of water quality deterioration, the pursuit of state-of-the-art decontamination technologies for a sustainable future never stops. Fitting into the framework of suitability, advanced oxidation processes have been demonstrated as powerful technologies to produce highly reactive radicals for the degradation of toxic and refractory contaminants. Therefore, investigations on their radical-induced degradation have been the subject of scientistic and engineering interests for decades. To better understand the transient nature of these radical species and rapid degradation processes, laser flash photolysis (LFP) has been considered as a viable and powerful technique due to its high temporal resolution and rapid response. Although a number of studies exploited LFP for one (or one class of) specific reaction(s), reactions of many possible contaminants with radicals are largely unknown. Therefore, there is a pressing need to critically review its implementation for kinetic quantification and mechanism elucidation. Within this context, we introduce the development process and milestones of LFP with emphasis on compositions and operation principles. We then compare the specificity and suitability of different spectral modes for monitoring radicals and their decay kinetics. Radicals with high environmental relevance, namely hydroxyl radical, sulfate radical, and reactive chlorine species, are selected, and we discuss their generation, detection, and implications within the frame of LFP. Finally, we highlight remaining challenges and future perspectives. This review aims to advance our understandings of the implementation of LFP in radical-induced transient processes, and yield new insights for extrapolating this pump-probe technique to make significant strides in environmental implications.
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Affiliation(s)
- Chu Chu
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Yiqi Yan
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Junye Ma
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Shengye Jin
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Richard Spinney
- Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, Ohio, 45221, USA
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, Ohio, 45221, USA; Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Haijun Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Ruiyang Xiao
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China.
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5
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Moore N, Wang C, Andrews S, Hofmann R. On the increasing competitiveness of UV/Cl to UV/H 2O 2 advanced oxidation as the organic carbon concentration increases. WATER RESEARCH 2023; 242:120227. [PMID: 37354844 DOI: 10.1016/j.watres.2023.120227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/12/2023] [Accepted: 06/12/2023] [Indexed: 06/26/2023]
Abstract
UV/Cl and UV/H2O2 are advanced oxidation processes (AOPs) used for drinking water treatment and water reuse. This work explored the hypothesis that UV/Cl becomes more competitive to UV/H2O2 at neutral-to-high pH as the concentration of total organic carbon (TOC) increases. Lab experiments and kinetic modelling were used to compare initial pseudo first-order contaminant decay rate coefficients between the AOPs at various pH and TOC conditions. The relative effect of increasing TOC concentrations on UV/Cl vs. UV/H2O2 depended on the pH, contaminant, and organic matter reactivity towards radicals. For example, while the reaction rate coefficients during both AOPs generally decreased with increasing TOC, the UV/Cl reaction rate coefficients for the solely •OH-reactive sucralose decreased 41-138% less than the UV/H2O2 coefficients as the TOC concentration was increased from 0 to 5 mg-C L-1. However, UV/Cl was more affected than UV/H2O2 when targeting caffeine (a contaminant reactive to chlorine radicals). The data were used to define TOC-pH conditions for which either AOP would be more energy-efficient, under a set of standard conditions. The results suggest that UV/Cl may be competitive to UV/H2O2 under a wider range of treatment scenarios than has been conventionally thought based on tests in pure water.
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Affiliation(s)
- Nathan Moore
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada.
| | - Chengjin Wang
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada; Department of Civil Engineering, University of Manitoba, 15 Gillson Street, Winnipeg, Manitoba R3T 5V6, Canada
| | - Susan Andrews
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada
| | - Ron Hofmann
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON M5S 1A4, Canada
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6
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Dalton EZ, Hoffmann EH, Schaefer T, Tilgner A, Herrmann H, Raff JD. Daytime Atmospheric Halogen Cycling through Aqueous-Phase Oxygen Atom Chemistry. J Am Chem Soc 2023; 145:15652-15657. [PMID: 37462273 DOI: 10.1021/jacs.3c03112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Halogen atoms are important atmospheric oxidants that have unidentified daytime sources from photochemical halide oxidation in sea salt aerosols. Here, we show that the photolysis of nitrate in aqueous chloride solutions generates nitryl chloride (ClNO2) in addition to Cl2 and HOCl. Experimental and modeling evidence suggests that O(3P) formed in the minor photolysis channel from nitrate oxidizes chloride to Cl2 and HOCl, which reacts with nitrite to form ClNO2. This chemistry is different than currently accepted mechanisms involving chloride oxidation by OH and could shift our understanding of daytime halogen cycling in the lower atmosphere.
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Affiliation(s)
- Evan Z Dalton
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Erik H Hoffmann
- Atmospheric Chemistry Department, Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany
| | - Thomas Schaefer
- Atmospheric Chemistry Department, Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany
| | - Andreas Tilgner
- Atmospheric Chemistry Department, Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany
| | - Hartmut Herrmann
- Atmospheric Chemistry Department, Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany
| | - Jonathan D Raff
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
- Paul H. O'Neill School of Public & Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
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7
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Han WR, Wang WL, Qiao TJ, Wang W, Su H, Xu CX, Wu QY. Ozone micro-bubble aeration using the ceramic ultrafiltration membrane with superior oxidation performance for 2, 4-D elimination. WATER RESEARCH 2023; 237:119952. [PMID: 37104935 DOI: 10.1016/j.watres.2023.119952] [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: 12/21/2022] [Revised: 03/16/2023] [Accepted: 04/06/2023] [Indexed: 05/09/2023]
Abstract
Micro-bubble aeration is an efficient way to promote ozonation performance, but the technology is challenged by extensive energy cost. Here, a ceramic ultrafiltration membrane was used to achieve ozone micro-bubble (0-80 µm) aeration in a simple way at gaseous pressures of 0.14-0.19 MPa. Compared with milli-bubble aeration, micro-bubble aeration increased the equilibrium aquatic O3 concentrations by 1.53-3.25 times and apparent O3 transfer rates by 3.12-3.35 times at pH 5.0-8.0. Consequently, the •OH yield was 2.67-3.54 times via faster O3 transfer to the aquatic solution followed by decomposition rather than interfacial reaction. Ozone micro-bubble aeration outperformed milli-bubble aeration, with the degradation kinetics of 2,4-D being 3.08-4.36 times higher. Both O3-oxidation and •OH oxidation were important to the promotion with the contributions being 35.8%-45.9% and 54.1%-64.2%, respectively. The operational and water matric conditions influenced the oxidation performance via both O3 oxidation and •OH oxidation, which is reported for the first time. In general, the ceramic membrane offered a low-energy approach of ozone micro-bubble aeration for efficient pollutant degradation. The O3 oxidation and •OH oxidation were proportionally promoted by ozone micro-bubble due to O3 transfer enhancement. Thus, the promotive mechanism can be interpreted as the synchronous enchantment on ozone exposure and •OH exposure for the first time.
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Affiliation(s)
- Wei-Ran Han
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Wen-Long Wang
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
| | - Tie-Jun Qiao
- Shenzhen Sinotsing environmental technologies company limited, Guangdong Province, Shenzhen 518055, China
| | - Wei Wang
- Beijing enterprises water group limited, Beijing 100020, China
| | - Hang Su
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Chen-Xin Xu
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Qian-Yuan Wu
- State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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8
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Liu S, Gu C, Zhang J, Luo C, Rong X, Yue G, Liu H, Wen J, Ma J. Degradation of 1,2,3-trichloropropane by unactivated persulfate and the implications for groundwater remediation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 865:161201. [PMID: 36581269 DOI: 10.1016/j.scitotenv.2022.161201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Persulfate (PS) is widely used as an in situ chemical oxidation (ISCO) technology for groundwater and soil remediation. While conventional theory generally assumes that PS needs to be "activated" to produce reactive radicals for pollutant degradation, herein, PS without explicit activation system was discovered for the degradation of 1,2,3-TCP with the generation of reactive oxidation species (ROS). Comparison of five common ISCO oxidants (PS, peroxymonosulfate, hydrogen peroxide, potassium permanganate, and sodium percarbonate) indicated that only unactivated PS was able to degrade 1,2,3-TCP in both pure water and 12 natural water samples. 50 μM 1,2,3-TCP degradation can be continued as long as there is enough PS (50 mM). The degradation rate of 1,2,3-TCP increased 450 % when the PS concentration increased from 10 mM to 50 mM and 500 % when the temperature increased from 25 °C to 45 °C. Electron paramagnetic resonance (EPR) analyzes, hydroxyl radicals (·OH) probe reaction and radical quenching experiments confirmed the involvement of both sulfate radicals (SO4·-) and ·OH that were responsible for 1,2,3-TCP degradation and ·OH played a more important role. HCO3-, Cl- and NOM are three groundwater matrix species that are most likely to inhibit PS oxidation of 1,2,3-TCP. Compared to activated PS, unactivated PS is more promising and more practical for groundwater remediation, since it has several advantages: (1) longer lifetime and better long-term availability; (2) ability of enduring contaminant degradation; (3) applicable for low-permeability zones remediation and potential to alleviate contaminant rebound or tailing problems; (4) environmental friendly; and (5) lower cost. Overall, results of this study show that unactivated PS is a promising in situ remediation technology that may be a good candidate for the most challenging low permeable zone remediation.
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Affiliation(s)
- Shuyu Liu
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Chunyun Gu
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Jiaxin Zhang
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Chaoyi Luo
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Xun Rong
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Gangsen Yue
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Hanyu Liu
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Jing Wen
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Jie Ma
- State Key Laboratory of Heavy Oil Processing, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China.
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9
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Application of BiOX Photocatalyst to Activate Peroxydisulfate Ion-Investigation of a Combined Process for the Removal of Organic Pollutants from Water. Catalysts 2023. [DOI: 10.3390/catal13030513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
The persulfate-based advanced oxidation processes employing heterogeneous photocatalysts to generate sulfate radicals (SO4•−) from peroxydisulfate ion (PDS, S2O82−) have been extensively investigated to remove organic pollutants. In this work, BiOX (X = Cl, Br, and I) photocatalysts were investigated to activate PDS and enhance the transformation rate of various organic substances under UV (398 nm) and Vis (400–700 nm) radiation. For BiOCl and BiOBr, in addition to excitability, the light-induced oxygen vacancies are decisive in the activity. Although without organic substances, the BiOI efficiency highly exceeds that of BiOBr and BiOCl for PDS activation (for BiOI, 15–20%, while for BiOBr and BiOCl, only 3–4% of the PDS transformed); each BiOX catalyst showed enhanced activity for 1,4-hydroquinone (HQ) transformation due to the semiquinone radical-initiated PDS activation. For sulfamethoxypyridazine (SMP), the transformation is driven by direct charge transfer, and the effect of PDS was less manifested. BiOI proved efficient for transforming various organic substances even under Vis radiation. The efficiency was enhanced by PDS addition (HQ is wholly transformed within 20 min, and SMP conversion increased from 40% to 90%) without damaging the catalyst; its activity did change over three consecutive cycles. Results related to the well-adsorbed trimethoprim (TRIM) and application of biologically treated domestic wastewater as a matrix highlighted the limiting factors of the method and visible light active photocatalyst, BiOI.
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10
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Li X, Shen J, Sun Z, Zhang W, Ma F, Gu Q. Insights into the impacts of chloride ions on the oxidation of 2,4-dinitrotoluene using ferrous activated persulfate: Removal efficiency, reaction mechanism, transformation pathway, and toxicity assessment. CHEMOSPHERE 2023; 317:137887. [PMID: 36657571 DOI: 10.1016/j.chemosphere.2023.137887] [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: 10/05/2022] [Revised: 01/02/2023] [Accepted: 01/14/2023] [Indexed: 06/17/2023]
Abstract
Persulfate/Fe2+-based advanced oxidation processes are widely used to treat water contaminated with 2,4-dinitrotoluene (DNT). However, the oxidation of DNT by persulfate/Fe2+ in the presence of the chloride ion (Cl⁻) has not been addressed, and the transformation pathways and toxicities of the intermediate products remain unclear. In this study, the effect of different Cl⁻ concentrations on the oxidation of DNT was investigated by persulfate/Fe2+. After the addition of 1.0 mM Cl⁻ and 6 h of oxidation, the removal efficiency of DNT increased by 68.5%. Scavenging experiments and an electron spin resonance analysis suggested that Cl⁻ caused hydroxyl radicals to increase in content in the persulfate/Fe2+ system, thus promoting the removal of DNT. Eight intermediate products of DNT were accurately detected using high-resolution mass spectrometry, and the transformation pathways of DNT were proposed, including hydroxylation/oxidation, elimination of the nitro group, and chlorination process. The acute and chronic toxicities of the intermediate products decreased during the oxidation process, but chlorinated by-products posed a higher toxicological risk. This result is vital for the practical application and environmental safety evaluation of persulfate/Fe2+-based advanced oxidation.
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Affiliation(s)
- Xiaodong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Jialun Shen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Zongquan Sun
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Wenwen Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Fujun Ma
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Qingbao Gu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
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11
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Promotion of CO2 reduction in a nanophotocatalyst by hydrogen peroxide. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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12
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Larbi Djaballah M, Belghit A, Dehane A, Merouani S, Hamdaoui O, Ashokkumar M. Radicals (●OH, Cl●, ClO● and Cl2●–) concentration profiles in the intensified degradation of reactive green 12 by UV/chlorine process: Chemical kinetic analysis using a validated model. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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13
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Hoang NT, Manh TD, Nguyen VT, Thy Nga NT, Mwazighe FM, Nhi BD, Hoang HY, Chang SW, Chung WJ, Nguyen DD. Kinetic study on methylene blue removal from aqueous solution using UV/chlorine process and its combination with other advanced oxidation processes. CHEMOSPHERE 2022; 308:136457. [PMID: 36116628 DOI: 10.1016/j.chemosphere.2022.136457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/25/2022] [Accepted: 09/11/2022] [Indexed: 06/15/2023]
Abstract
This study investigated the kinetic degradation of methylene blue (MB) by a UV/chlorine process and its combination with other advanced oxidation processes. The ∙OH and reactive chlorine species (RCS: Cl∙, ClO∙, etc.) were the primary reactive species, which accounted for 56.7% and 37.6% of MB degradation at pH 7, respectively. The second-order rate constant of Cl∙ towards MB was calculated to be 2.8 × 109 M-1 s-1. When the pH increased from 3 to 7, kMB by ∙OH increased from 0.15 to 0.21 min-1 before being reduced to 0.11 min-1 at pH 11. kMB by RCS continuously reduced from 0.16 to 0.13 min-1 when the pH was increased to 11. Humic acid (HA), Br-, and Cl- inhibited the degradation with kMB in the order: kMB (in HA) < kMB (in Br-) < kMB (in Cl-). HCO3- increased kMB from 0.37 to 0.48 min-1. The experimental and modeling methods fit well, indicating the effectiveness of using Kintecus® in predicting concentrations of free radicals in complex water matrices. TOC removal was achieved at 60% after 30 min in a control process and it was strongly inhibited by the presence of HA, with 22% removal achieved at 5 mgc L-1 HA. UV/chlorine/electrochemical oxidation (UV/chlorine/EO) significantly improves kMB from 0.37 to 0.94 min-1 at a high current (240 mA), while UV/chlorine/H2O2 decreased kMB at a low concentration of 0.01 mM H2O2 (kMB decreased by 6.1%). The results indicate that the energy cost for UV irradiation was the main cost in MB treatment in both UV/chlorine and UV/persulfate (UV/PS) processes, accounting for 91% and 84%, respectively.
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Affiliation(s)
- Nguyen Tien Hoang
- The University of Da Nang, University of Science and Education, 459 Ton Duc Thang st., Lien Chieu, Da Nang 550000, Viet Nam.
| | - Tran Duc Manh
- The University of Da Nang, University of Science and Education, 459 Ton Duc Thang st., Lien Chieu, Da Nang 550000, Viet Nam
| | - Vo Thang Nguyen
- The University of Da Nang, University of Science and Education, 459 Ton Duc Thang st., Lien Chieu, Da Nang 550000, Viet Nam
| | - Nguyen Thi Thy Nga
- The University of Da Nang, University of Science and Education, 459 Ton Duc Thang st., Lien Chieu, Da Nang 550000, Viet Nam
| | - Fredrick M Mwazighe
- Department of Chemistry, Faculty of Science and Technology, University of Nairobi, P. O. Box 30197, 00100, Nairobi, Kenya
| | - Bui D Nhi
- Faculty of Chemical and Environmental Technology, Viet Tri University of Industry, Phu Tho, Viet Nam.
| | - Hien Y Hoang
- Center for Advanced Chemistry, Institute of Research and Development, Duy Tan University, 03 Quang Trung, Danang, 550000, Viet Nam; The Faculty of Environmental and Chemical Engineering, Duy Tan University, 03 Quang Trung, Danang, 550000, Viet Nam
| | - S Woong Chang
- Department of Environmental Energy Engineering, Kyonggi University, 442-760, Republic of Korea
| | - W Jin Chung
- Department of Environmental Energy Engineering, Kyonggi University, 442-760, Republic of Korea
| | - D Duc Nguyen
- Department of Environmental Energy Engineering, Kyonggi University, 442-760, Republic of Korea; Faculty of Environmental and Food Engineering, Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, HCM City, 755414, Viet Nam.
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14
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The destruction of trichloroethylene by zinc dioxide using a modified Fenton reaction: Performance and a preliminary mechanism. RESEARCH ON CHEMICAL INTERMEDIATES 2022. [DOI: 10.1007/s11164-022-04837-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Wojnárovits L, Wang J, Chu L, Takács E. Rate constants of chlorine atom reactions with organic molecules in aqueous solutions, an overview. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:55492-55513. [PMID: 35688978 PMCID: PMC9374632 DOI: 10.1007/s11356-022-20807-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/10/2022] [Indexed: 05/15/2023]
Abstract
Rate constants of chlorine atom (Cl•) reactions (kCl•) determined using a large variation of experimental methods, including transient measurements, steady-state and computation techniques, were collected from the literature and were discussed together with the reaction mechanisms. The kCl• values are generally in the 108-109 mol-1 dm3 s-1 range when the basic reaction between the Cl• and the target molecule is H-atom abstraction. When Cl• addition to double bonds dominates the interaction, the kCl• values are in the 1 × 109-2 × 1010 mol-1 dm3 s-1 range. In the kCl• = 1 × 1010-4 × 1010 mol-1 dm3 s-1 range, single-electron-transfer reactions may also contribute to the mechanism. The Cl• reactions with organic molecules in many respects are similar to those of •OH, albeit Cl• seems to be less selective as •OH. However, there is an important difference, as opposed to Cl• in the case of •OH single-electron-transfer reactions have minor importance. The uncertainty of Cl• rate constant determinations is much higher than those of •OH. Since Cl• reactions play very important role in the emerging UV/chlorine water purification technology, some standardization of the rate constant measuring techniques and more kCl• measurements are recommended.
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Affiliation(s)
- László Wojnárovits
- Institute for Energy Security and Environmental Safety, Centre for Energy Research, Radiation Chemistry Department, ELKH, Budapest, Hungary
| | - Jianlong Wang
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Libing Chu
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Erzsébet Takács
- Institute for Energy Security and Environmental Safety, Centre for Energy Research, Radiation Chemistry Department, ELKH, Budapest, Hungary.
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16
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Chen Y, Vu HC, Miller CJ, Garg S, Pan D, Waite TD. Comparative Experimental and Computational Studies of Hydroxyl and Sulfate Radical-Mediated Degradation of Simple and Complex Organic Substrates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8819-8832. [PMID: 35549159 DOI: 10.1021/acs.est.2c00686] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Persulfate (PS)-based advanced oxidation processes (AOPs) have been promoted as alternatives to H2O2-based AOPs. To gauge the potential of this technology, the PS/Fe(II) and Fenton (H2O2/Fe(II)) processes were comparatively evaluated using formate as a simple target compound and nanofiltration concentrate from a municipal wastewater treatment plant as a complex suite of contaminants with the aid of kinetic modeling. In terms of the short-term rate and extent of mineralization of formate and the nanofiltration concentrate, PS/Fe(II) is less effective due to slow Fe(II)/Fe(III) cycling attributable to the scavenging of superoxide by PS. However, in the concentrate treatment, PS/Fe(II) provided a sustained removal of total organic carbon (TOC), with ∼81% removed after 7 days with SO4•- consistently produced via homolysis of the long-life PS. In comparison, H2O2/Fe(II) exhibited limited TOC removal over ∼57% after 10 h due to the futile consumption of H2O2 by HO•. PS/Fe(II) also offers better performance at transforming humic-like moieties to more biodegradable compounds as a result of chlorine radicals formed by the reaction of SO4•- with the matrix constituents present in the concentrate. The application of PS/Fe(II) is, however, subject to the limitations of slow oxidation of organic contaminants, release of sulfate, and formation of chlorinated byproducts.
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Affiliation(s)
- Yufan Chen
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Huong Chi Vu
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Christopher J Miller
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Shikha Garg
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Dai Pan
- Beijing Originwater Technology Co., Ltd, Beijing 102206, China
| | - T David Waite
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
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17
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Palma D, Khaled A, Sleiman M, Voyard G, Richard C. Effect of UVC pre-irradiation on the Suwannee river Natural Organic Matter (SRNOM) photooxidant properties. WATER RESEARCH 2021; 202:117395. [PMID: 34273776 DOI: 10.1016/j.watres.2021.117395] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 06/13/2023]
Abstract
The present study aimed to investigate the changes in the chemical composition, and in the optical and photooxidant properties of Suwannee River Natural Organic Matter (SRNOM) induced by UVC (254 nm) treatment. The extent of the photodegradation was first assessed by UV-visible/fluorescence spectroscopies and organic carbon analysis. An in-depth investigation of the chemical changes was also conducted using liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry after derivatizations. A series of mono, di and tricarbonyls and mono and dicarboxylic acids in C1C6 were identified in samples irradiated from 1 to 4 h. After 3 h of irradiation, carbonyls accounted for 46% of the organic carbon remaining in solution whereas carboxylic acids represented about 2%. Then, we investigated the modifications of the photooxidant properties of SRNOM induced by these chemical changes. At 254 nm, UVC pre-irradiated SRNOM photodegraded glyphosate 29 times faster than original SRNOM and the reaction was fully inhibited by 2-propanol (5 × 10-3 M). This enhanced photooxidant properties at 254 nm toward glyphosate was therefore reasonably due to •OH radicals formation, as confirmed by additional ESR measurements. A mechanism involving a chain reaction was proposed based on independent experiments conducted on carbonyl compounds, particularly pyruvic acid and acetone. The findings of this study show that UVC pre-treatment of NOM can enhance the removal of water pollutants and suggests a possible integration of a NOM pre-activation step in engineered water treatment sytems.
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Affiliation(s)
- Davide Palma
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, ICCF, F-63000 Clermont-Ferrand, France
| | - Amina Khaled
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, ICCF, F-63000 Clermont-Ferrand, France
| | - Mohamad Sleiman
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, ICCF, F-63000 Clermont-Ferrand, France
| | - Guillaume Voyard
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, ICCF, F-63000 Clermont-Ferrand, France
| | - Claire Richard
- Université Clermont Auvergne, CNRS, SIGMA-Clermont, ICCF, F-63000 Clermont-Ferrand, France.
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18
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Wojnárovits L, Takács E. Rate constants of dichloride radical anion reactions with molecules of environmental interest in aqueous solution: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:41552-41575. [PMID: 34086177 PMCID: PMC8354983 DOI: 10.1007/s11356-021-14453-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 05/13/2021] [Indexed: 05/14/2023]
Abstract
Natural waters, water droplets in the air at coastal regions and wastewaters usually contain chloride ions (Cl-) in relatively high concentrations in the milimolar range. In the reactions of highly oxidizing radicals (e.g., •OH, •NO3, or SO4•-) in the nature or during wastewater treatment in advanced oxidation processes the chloride ions easily transform to chlorine containing radicals, such as Cl•, Cl2•-, and ClO•. This transformation basically affects the degradation of organic molecules. In this review about 400 rate constants of the dichloride radical anion (Cl2•-) with about 300 organic molecules is discussed together with the reaction mechanisms. The reactions with phenols, anilines, sulfur compounds (with sulfur atom in lower oxidation state), and molecules with conjugated electron systems are suggested to take place with electron transfer mechanism. The rate constant is high (107-109 M-1 s-1) when the reduction potential the one-electron oxidized species/molecule couple is well below that of the Cl2•-/2Cl- couple.
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Affiliation(s)
- László Wojnárovits
- Radiation Chemistry Department, Institute for Energy Security and Environmental Safety, Centre for Energy Research, H-1121 Konkoly-Thege Miklós út, Budapest, 29-33, Hungary
| | - Erzsébet Takács
- Radiation Chemistry Department, Institute for Energy Security and Environmental Safety, Centre for Energy Research, H-1121 Konkoly-Thege Miklós út, Budapest, 29-33, Hungary.
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19
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Wang X, Xu P, Yang C, Shen T, Qu J, Wang P, Zhang G. Enhanced 4-FP removal with MnFe 2O 4 catalysts under dielectric barrier discharge plasma: Economical synthesis, catalytic performance and degradation mechanism. JOURNAL OF HAZARDOUS MATERIALS 2021; 414:125602. [PMID: 34030426 DOI: 10.1016/j.jhazmat.2021.125602] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/23/2021] [Accepted: 03/03/2021] [Indexed: 06/12/2023]
Abstract
The dielectric barrier discharge plasma (DBDP) process has received extensive attention for the removal of organic contaminants from water. A novel microwave-assisted hydrothermal method was used to easily and rapidly synthesize MnFe2O4 catalysts. Based on the DBDP process, MnFe2O4 can enhance 4-fluorophenol (4-FP) abatement from 44.15% to 58.78% through the catalysis within 18 min. Then, the adjunction of O3 generated by discharge can further boost 4-FP degradation to 94.94%. After the whole optimization process is complete, the associated pseudo-first-order reaction kinetic constant and energy efficiency were enhanced from 0.0327 to 0.1536 min-1 and 2067.13 mg kW h-1 to 4444.75 mg kW h-1, respectively. With the help of the condition, blank and radical capture experiments, the catalytic performance caused by MnFe2O4 and O3 was attributed to the joint action of Fenton-like reactions, photocatalysis (ultraviolet, UV), photoassisted Fenton reactions and O3 catalysis. The overall downward trend of the possible intermediate toxicities indicated that the DBDP/MnFe2O4/O3 process can effectively remove and mineralize 4-FP without the generation of more toxic intermediates. In addition, during the 5 cycles, MnFe2O4 can maintain excellent recovery, efficiency and durability. In summary, the coupling of discharge plasma and MnFe2O4 sheds new light on catalysis for wastewater treatment.
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Affiliation(s)
- Xiaojing Wang
- College of Resource and Environment, Qingdao Engineering Research Center for Rural Environment, Qingdao Agricultural University, Qingdao 266109, PR China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Peng Xu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Chunyan Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Tianyao Shen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jianhua Qu
- School of Resources and Environment, Northeast Agricultural University, Harbin 150030, PR China
| | - Peng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Guangshan Zhang
- College of Resource and Environment, Qingdao Engineering Research Center for Rural Environment, Qingdao Agricultural University, Qingdao 266109, PR China.
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20
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Rabani J, Mamane H, Pousty D, Bolton JR. Practical Chemical Actinometry-A Review. Photochem Photobiol 2021; 97:873-902. [PMID: 34124787 DOI: 10.1111/php.13429] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/05/2021] [Indexed: 01/03/2023]
Abstract
Actinometers are physical or chemical systems that can be employed to determine photon fluxes. Chemical actinometers are photochemical systems with known quantum yields that can be employed to determine accurate photon fluxes for specific photochemical reactions. This review explores in detail several practical chemical actinometers (ferrioxalate, iodide-iodate, uranyl oxalate, nitrate, uridine, hydrogen peroxide and several actinometers for the vacuum ultraviolet). Each actinometer is described with recommended conditions for its use.
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Affiliation(s)
- Joseph Rabani
- The Accelerator Laboratory, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hadas Mamane
- School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Dana Pousty
- School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
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21
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Chen M, Rholl CA, He T, Sharma A, Parker KM. Halogen Radicals Contribute to the Halogenation and Degradation of Chemical Additives Used in Hydraulic Fracturing. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:1545-1554. [PMID: 33449615 DOI: 10.1021/acs.est.0c03685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In hydraulic fracturing fluids, the oxidant persulfate is used to generate sulfate radical to break down polymer-based gels. However, sulfate radical may be scavenged by high concentrations of halides in hydraulic fracturing fluids, producing halogen radicals (e.g., Cl•, Cl2•-, Br•, Br2•-, and BrCl•-). In this study, we investigated how halogen radicals alter the mechanisms and kinetics of the degradation of organic chemicals in hydraulic fracturing fluids. Using a radical scavenger (i.e., isopropanol), we determined that halogenated products of additives such as cinnamaldehyde (i.e., α-chlorocinnamaldehyde and α-bromocinnamaldehyde) and citrate (i.e., trihalomethanes) were generated via a pathway involving halogen radicals. We next investigated the impact of halogen radicals on cinnamaldehyde degradation rates. The conversion of sulfate radicals to halogen radicals may result in selective degradation of organic compounds. Surprisingly, we found that the addition of halides to convert sulfate radicals to halogen radicals did not result in selective degradation of cinnamaldehyde over other compounds (i.e., benzoate and guar), which may challenge the application of radical selectivity experiments to more complex molecules. Overall, we find that halogen radicals, known to react in advanced oxidative treatment and sunlight photochemistry, also contribute to the unintended degradation and halogenation of additives in hydraulic fracturing fluids.
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Affiliation(s)
- Moshan Chen
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Carter A Rholl
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Tianchen He
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Aditi Sharma
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Kimberly M Parker
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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22
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Xiao Y, Liu X, Huang Y, Kang W, Wang Z, Zheng H. Roles of hydroxyl and carbonate radicals in bisphenol a degradation via a nanoscale zero-valent iron/percarbonate system: influencing factors and mechanisms. RSC Adv 2021; 11:3636-3644. [PMID: 35424279 PMCID: PMC8694019 DOI: 10.1039/d0ra08395j] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/19/2020] [Indexed: 01/15/2023] Open
Abstract
In this work, nanoscale-zero-valent iron (nZVI) was applied to activate sodium percarbonate (SPC) to eliminate bisphenol A (BPA), which poses a risk to ecological and human health as a typical endocrine disruptor. The influence of nZVI loading, SPC dosing, initial pH, and the presence of inorganic anions (including Cl-, HPO4 2-, NO3 - and NO2 -) and humic acid on BPA removal by the nZVI/SPC system were investigated. Based on the scavenger test results, ˙OH and CO3˙- participated in the degradation of BPA, and ˙OH was illustrated to be the dominant radical. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis suggested that surface iron oxide generation, electron transfer and Fe2+ release were the main processes of the SPC activation by nZVI. Moreover, BPA transformation products were detected by LC-MS allowing the proposal of a possible degradation pathway of BPA. Along with the degradation of the parent compound BPA, the total organic carbon (TOC) gradually decreased, while the bio-toxicity increased at the initial stage of the reaction (0-3 min) and then decreased to a lower level rapidly at 20 min. Overall, this study evidenced the feasibility of the nZVI/SPC system to efficiently degrade BPA, broadening the applications of nZVI in wastewater treatment.
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Affiliation(s)
- Yulun Xiao
- Faculty of Science, Monash University Clayton VIC 3800 Australia
- Hubei Key Laboratory of Mine Environmental Pollution Control and Remediation, Hubei Polytechnic University Huangshi 435003 China +86-0714-6348286 +86-0714-6348671
| | - Xiang Liu
- School of Environmental Studies, China University of Geosciences Wuhan 430074 China
| | - Ying Huang
- College of Chemical and Biological Engineering, Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University Hangzhou 310027 China
| | - Wei Kang
- School of Environmental Science and Engineering, Hubei Polytechnic University Huangshi 435003 China
| | - Zhen Wang
- Hubei Key Laboratory of Mine Environmental Pollution Control and Remediation, Hubei Polytechnic University Huangshi 435003 China +86-0714-6348286 +86-0714-6348671
- School of Environmental Studies, China University of Geosciences Wuhan 430074 China
| | - Han Zheng
- Hubei Key Laboratory of Mine Environmental Pollution Control and Remediation, Hubei Polytechnic University Huangshi 435003 China +86-0714-6348286 +86-0714-6348671
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23
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Zhang X, Chen Z, Kang J, Zhao S, Wang B, Yan P, Deng F, Shen J, Chu W. UV/ peroxymonosulfate process for degradation of chloral hydrate: Pathway and the role of radicals. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123837. [PMID: 33113746 DOI: 10.1016/j.jhazmat.2020.123837] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/27/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
In this study, kinetics, influencing factors and potential mechanisms involved in the degradation of chloral hydrate (CH) by UV/peroxymonosulfate (PMS) process were demonstrated. The degradation rate of CH could reach 89.6% by UV254/PMS process, significantly exceeding UV300/PMS (0.7%), UV350/PMS (6.3%), UV254 direct photolysis (9.0%) and PMS alone (0.0%) processes. CH degradation in UV254/PMS system followed pseudo first-order degradation kinetics with an apparent rate constant of 0.186 min-1, which was suppressed by Cl- and HCO3-. The optimal pH for CH degradation was around 5.0. Direct mineralization accounted for the CH degradation in UV/PMS system. Interestingly, the addition of PMS at the neutral condition before UV irradiation transferred CH into trichloroacetic acid (TCAA). The transformation efficiency of CH into TCAA at 10 min was enhanced from 2.17%-40.38% with the elevation of initial pH from 7.0-8.0. The subsequent exposure of UV lamps ceased the transformation of CH into TCAA and facilitated the direct mineralization of CH, but it did not work in the refractory TCAA degradation. Finally, it was revealed that HO predominantly participated CH degradation in UV/PMS process, while O2- was responsible for the transformation of CH into TCAA by addition of PMS before UV irradiation.
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Affiliation(s)
- Xiaoxiao Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jing Kang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Shengxin Zhao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Binyuan Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Pengwei Yan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Fengxia Deng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Wei Chu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
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24
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Ali M, Shan A, Sun Y, Gu X, Lyu S, Zhou Y. Trichloroethylene degradation by PVA-coated calcium peroxide nanoparticles in Fe(II)-based catalytic systems: enhanced performance by citric acid and nanoscale iron sulfide. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:3121-3135. [PMID: 32902746 DOI: 10.1007/s11356-020-10678-3] [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: 04/11/2020] [Accepted: 08/30/2020] [Indexed: 06/11/2023]
Abstract
In this study, the enhanced trichloroethylene (TCE) degradation performance was investigated by polyvinyl alcohol coated calcium peroxide nanoparticles (PVA@nCP) as an oxidant in Fe(II)-based catalytic systems. The nanoscale iron sulfide (nFeS), having an average particle size of 115.4 nm, was synthesized in the laboratory and characterized by SEM, TEM, HR-TEM along with EDS elemental mapping, XRD, FTIR, ICP-OES, and XPS techniques. In only ferrous iron catalyzed system (PVA@nCP/Fe(II)), TCE degradation was recorded at 58.9% in 6 h. In comparison, this value was increased to 97.5% or 99.7% with the addition of citric acid (CA) or nFeS in PVA@nCP/Fe(II) system, respectively. A comparative study was performed with optimum usages of chemical reagents in both PVA@nCP/Fe(II)/CA and PVA@nCP/Fe(II)/nFeS systems. Further, the probe compounds tests and electron paramagnetic resonance (EPR) analysis confirmed the generation of reactive oxygen species. The scavenging experiments elucidated the dominant role of HO• to TCE degradation, particularly in PVA@nCP/Fe(II)/nFeS system. Both CA and nFeS strengthened PVA@nCP/Fe(II) system, but displayed completely different mechanisms in the enhancement of active radicals generation; hence, their different contribution to TCE degradation. The acidic environment was favorable for TCE degradation, and a high concentration of HCO3- inhibited TCE removal in both systems. Conclusively, compared to PVA@nCP/Fe(II)/nFeS system, PVA@nCP/Fe(II)/CA system resulted in encouraging TCE degradation outcomes in actual groundwater, showing great potential for prolonged benefits in the remediation of TCE polluted groundwater. Graphical abstract.
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Affiliation(s)
- Meesam Ali
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
- Department of Chemical Engineering, Muhammad Nawaz Sharif University of Engineering and Technology, Multan, 60000, Pakistan
| | - Ali Shan
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
- Department of Environmental Sciences, The University of Lahore, Lahore, 46000, Pakistan
| | - Yong Sun
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Xiaogang Gu
- Shanghai Urban Construction Design & Research Institute (Group) Co., Ltd, 3447 Dongfang Road, Shanghai, 200125, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Yanbo Zhou
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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25
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Liu Y, Wang T, Qu G, Jia H. High-efficient decomplexation of Cu-HA by discharge plasma: Process and mechanisms. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117137] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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26
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Li S, Ao X, Li C, Lu Z, Cao W, Wu F, Liu S, Sun W. Insight into PPCP degradation by UV/NH 2Cl and comparison with UV/NaClO: Kinetics, reaction mechanism, and DBP formation. WATER RESEARCH 2020; 182:115967. [PMID: 32721700 DOI: 10.1016/j.watres.2020.115967] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 04/21/2020] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
The UV/NH2Cl process is an emerging advanced oxidation process (AOP) that is greatly effective in degrading pharmaceuticals and personal care products (PPCPs). However, detailed information regarding the process is lacking. The degradation of ibuprofen (IBP, an electron-withdrawing PPCP) and naproxen (NPX, an electron-donating PPCP) in UV/NH2Cl and UV/NaClO processes was performed to investigate the applicability and security of the UV/NH2Cl process and compare with those of UV/NaClO. UV/NH2Cl was effective in degrading both IBP and NPX and the degradation followed pseudo-first order kinetics (kIBP = 0.0037 cm2/mJ and kNPX = 0.0044 cm2/mJ). This indicated the broad applicability of UV/NH2Cl to different kinds of PPCPs. Ranges of values of UV intensity (0.3-1.0 mW/cm2) and pH (6.0-8.0) showed little effect on the degradation of PPCPs by UV/NH2Cl based on UV Dose but HCO3- (2-8 mM), natural organic matter (NOM, 2-8 mg/L), and the natural water matrixes were inhibitory. Increasing the dosage of NH2Cl from 0.15 mM to 0.75 mM, resulted in an even increase of kIBP; however, kNPX increased slowly after 0.3 mM NH2Cl. Mechanism experiments involving nitrobenzene showed that •OH was the major radical involved in degrading IBP and NPX via UV/NH2Cl. The electron spin resonance spectroscopy and kinetic modeling results also indicated the larger amount of •OH and weaker reactive chlorine species (mainly ClO• and ClO2•) in UV/NH2Cl compared with UV/NaClO. Compared to UV/NaClO in synthetic and natural water, UV/NH2Cl was a more stable degrader with little pH- and substrate-dependence, while UV/NaClO preferred degrading the electron-donating PPCP and at low pH. The UV/NH2Cl produced less halogenated disinfection byproducts (DBPs) (even nitrogenous DBPs) and was less cytotoxic theoretically than UV/NaClO based on the DBPs included in this study. Thus UV/NH2Cl process may be an effective AOP for water treatment.
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Affiliation(s)
- Simiao Li
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Xiuwei Ao
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Chen Li
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Zedong Lu
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Wenfeng Cao
- Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Fangfang Wu
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Shuming Liu
- School of Environment, Tsinghua University, Beijing, 100084, China
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing, 100084, China.
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Bulman DM, Remucal CK. Role of Reactive Halogen Species in Disinfection Byproduct Formation during Chlorine Photolysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:9629-9639. [PMID: 32598837 DOI: 10.1021/acs.est.0c02039] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The multiple reactive oxidants produced during chlorine photolysis effectively degrade organic contaminants during water treatment, but their role in disinfection byproduct (DBP) formation is unclear. The impact of chlorine photolysis on dissolved organic matter (DOM) composition and DBP formation is investigated using lake water collected after coagulation, flocculation, and filtration at pH 6.5 and pH 8.5 with irradiation at three wavelengths (254, 311, and 365 nm). The steady-state concentrations of hydroxyl radical and chlorine radical decrease by 38-100% in drinking water compared to ultrapure water, which is primarily attributed to radical scavenging by natural water constituents. Chlorine photolysis transforms DOM through multiple mechanisms to produce DOM that is more aliphatic in nature and contains novel high molecular weight chlorinated DBPs that are detected via high-resolution mass spectrometry. Quenching experiments demonstrate that reactive chlorine species are partially responsible for the formation of halogenated DOM, haloacetic acids, and haloacetonitriles, whereas trihalomethane formation decreases during chlorine photolysis. Furthermore, DOM transformation primarily due to direct photolysis alters DOM such that it is more reactive with chlorine, which also contributes to enhanced formation of novel DBPs during chlorine photolysis.
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Affiliation(s)
- Devon Manley Bulman
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 North Park Street, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 North Park Street, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, 660 North Park Street, Madison, Wisconsin 53706, United States
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Huang J, Danish M, Jiang X, Tang P, Sui Q, Qiu Z, Lyu S. Trichloroethylene degradation performance in aqueous solution by Fe(II) activated sodium percarbonate in the presence of surfactant sodium dodecyl sulfate. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:1142-1151. [PMID: 32060999 DOI: 10.1002/wer.1309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
The performance of trichloroethylene (TCE) degradation by sodium percarbonate (SPC) activated with Fe(II) in the presence of 3.0 g/L sodium dodecyl sulfate (SDS) as well as the role of SDS in the SPC/Fe(II) system was investigated since SDS is a common surfactant used in groundwater remediation for improving TCE dissolution to the aqueous phase. The results showed that though the introduction of SDS could inhibit the TCE degradation, the inhibiting effect was less with the increasing SDS dose. In the presence of SDS, TCE could be completely removed with the SPC/Fe(II)/TCE molar ratio of 40/80/1. Experiments with free radical probe compounds and radical scavengers elucidated that TCE was mainly oxidized by both HO· and O 2 - · . A weakly acidic environment was more favorable to TCE degradation. Nevertheless, HCO 3 - at a high concentration had a strongly inhibitive effect on the TCE degradation but the influence of Cl- was negligible. Finally, the excellent TCE degradation achieved in actual groundwater demonstrated that Fe(II) activated SPC technique was applicable in the remediation of TCE contaminated groundwater in the presence of SDS. PRACTITIONER POINTS: The effects of SDS were evaluated SPC/Fe(II)/SDS system applied to remediate TCE The mechanism of HO· and O 2 - · generation had been investigated Cl- and HCO 3 - affected TCE degradation at different levels The performance of TCE removal in actual groundwater had been studied.
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Affiliation(s)
- Jingyao Huang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Muhammad Danish
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
- Chemical Engineering Department, University of Engineering and Technology (UET), Lahore, Pakistan
| | - Xihao Jiang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Ping Tang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
| | - Shuguang Lyu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, China
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29
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Wang X, Sun M, Zhao Y, Wang C, Ma W, Wong MS, Elimelech M. In Situ Electrochemical Generation of Reactive Chlorine Species for Efficient Ultrafiltration Membrane Self-Cleaning. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:6997-7007. [PMID: 32356975 DOI: 10.1021/acs.est.0c01590] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Reactive membranes based on hydroxyl radical generation are hindered by the need for chemical dosing and complicated module and material design. Herein, we utilize an electrochemical approach featuring in situ generation of reactive (radical) chlorine species (RCS) through anodization of chloride ions for membrane self-cleaning. A hybridized carbon nanotube (CNT)-functionalized ceramic membrane (h-CNT/CM), possessing high hydrophilicity, permeability, and conductivity, was fabricated. Using carbamazepine (CBZ) as a probe, we confirmed the presence of RCS in the electrified h-CNT/CM. The rapid and complete degradation of CBZ in a single-pass ultrafiltration indicates a high localized RCS concentration within the three-dimensional porous CNT interwoven layer. We further demonstrate that the electrogeneration of RCS is a critical prestep for free chlorine (HClO and ClO-) formation. The self-cleaning efficiency of the membrane after fouling with a model organic foulant (alginate) was assessed using an electrified cross-flow membrane filtration system. The fouled h-CNT/CM exhibits a near complete water flux recovery following a short (1 min) self-cleaning with an applied voltage of 3 or 4 V and feed solutions of 100 or 10 mM sodium chloride, respectively. Considering the superior performance of the RCS-mediated self-cleaning compared to conventional membrane chemical cleaning using sodium hypochlorite, our results exemplify an effective strategy for in situ electrogeneration of RCS to achieve a highly efficient membrane self-cleaning.
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Affiliation(s)
- Xiaoxiong Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Meng Sun
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Yumeng Zhao
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chi Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- School of Environment, Northeast Normal University, Changchun 130024, China
| | - Wen Ma
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Michael S Wong
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Houston, Texas 77005, United States
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Houston, Texas 77005, United States
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30
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Photochemistry of the Cloud Aqueous Phase: A Review. Molecules 2020; 25:molecules25020423. [PMID: 31968643 PMCID: PMC7024559 DOI: 10.3390/molecules25020423] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/12/2020] [Accepted: 01/16/2020] [Indexed: 11/19/2022] Open
Abstract
This review paper describes briefly the cloud aqueous phase composition and deeply its reactivity in the dark and mainly under solar radiation. The role of the main oxidants (hydrogen peroxide, nitrate radical, and hydroxyl radical) is presented with a focus on the hydroxyl radical, which drives the oxidation capacity during the day. Its sources in the aqueous phase, mainly through photochemical mechanisms with H2O2, iron complexes, or nitrate/nitrite ions, are presented in detail. The formation rate of hydroxyl radical and its steady state concentration evaluated by different authors are listed and compared. Finally, a paragraph is also dedicated to the sinks and the reactivity of the HO• radical with the main compounds found in the cloud aqueous phase. This review presents an assessment of the reactivity in the cloud aqueous phase and shows the significant potential impact that this medium can have on the chemistry of the atmosphere and more generally on the climate.
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31
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Lin MH, Mehraeen S, Cheng G, Rusinek C, Chaplin BP. Role of Near-Electrode Solution Chemistry on Bacteria Attachment and Poration at Low Applied Potentials. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:446-455. [PMID: 31793293 DOI: 10.1021/acs.est.9b04313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This research investigated mechanisms for biofouling control at boron-doped diamond (BDD) electrode surfaces polarized at low applied potentials (e.g., -0.2 to 1.0 V vs Ag/AgCl), using Pseudomonas aeruginosa as a model organism. Results indicated that electrostatic interactions between bacteria and ionic electrode functional groups facilitated bacteria attachment at the open-circuit potential (OCP). However, under polarization, the applied potential governed these electrostatic interactions and electrochemical reactions resulted in surface bubble formation and near-surface pH modulation that decreased surface attachment under anodic conditions. The poration of the attached bacteria occurred at OCP conditions and increased with the applied potential. Scanning electrochemical microscopy (SECM) provided near-surface pH and oxidant formation measurements under anodic and cathodic polarizations. The near-surface pH was 3.1 at 1.0 V vs Ag/AgCl and 8.0 at -0.2 V vs Ag/AgCl and was possibly a contributor to bacteria poration. Interpretation of SECM data using a reactive transport model allowed for a better understanding of the near-electrode chemistry. Under cathodic conditions, the primary oxidant formed was H2O2, and under anodic conditions, a combination of H2O2, Cl•, HO2•, Cl2•-, and Cl2 formations likely contributed to bacteria poration at potentials as low as 0.5 V vs Ag/AgCl.
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Affiliation(s)
- Meng-Hsuan Lin
- Department of Chemical Engineering, University of Illinois at Chicago, 945 West Taylor Street, Chicago, Illinois 60607, United States
| | - Shafigh Mehraeen
- Department of Chemical Engineering, University of Illinois at Chicago, 945 West Taylor Street, Chicago, Illinois 60607, United States
| | - Gang Cheng
- Department of Chemical Engineering, University of Illinois at Chicago, 945 West Taylor Street, Chicago, Illinois 60607, United States
| | - Cory Rusinek
- MSU-Fraunhofer Center for Coatings and Diamond Technologies, 1449 Engineering Research Court, East Lansing, Michigan 48824, United States
| | - Brian P Chaplin
- Department of Chemical Engineering, University of Illinois at Chicago, 945 West Taylor Street, Chicago, Illinois 60607, United States
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32
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Long L, Bu Y, Chen B, Sadiq R. Removal of urea from swimming pool water by UV/VUV: The roles of additives, mechanisms, influencing factors, and reaction products. WATER RESEARCH 2019; 161:89-97. [PMID: 31181450 DOI: 10.1016/j.watres.2019.05.098] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/05/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
To discover an applicable technology for urea abatement from swimming pool water (SPW), this study compared the performances of seven ultraviolet (UV)-based technologies on urea removal, including UV alone, UV coupled with hydrogen peroxide (UV/H2O2), sulfite (UV/Na2SO3), potassium persulfate (UV/K2S2O8), a combination of UV and vacuum UV (UV/VUV), and UV/VUV in tandem with either H2O2 (VUV/H2O2) or potassium persulfate (VUV/K2S2O8). Among them, UV and UV/Na2SO3 showed little removal ability, and UV/H2O2 removed only 12.8% of urea within 3-h experiments, while UV/VUV degraded 71.7% of urea without introducing substantial total dissolved solids (TDS). Therefore, UV/VUV was considered as a promising technology for further exploration. In comparison, although UV/K2S2O8 exhibited higher urea removal than UV/VUV, it caused dramatic increases of TDS, which made the regulatory threshold for the TDS increment difficult to maintain. Within UV/VUV studies, some common components in SPW (e.g., cyanuric acid, humic acid, nitrate, and bicarbonate) inhibited the removal process, whereas chloride and sulfate facilitated it, while free chlorine at doses ≤ 3 mg-Cl2/L and pH levels from 6.8 to 8.0 imposed little impact on urea degradation. Overall, UV/VUV degraded 40.0% and 22.2% of urea from tap water and SPW, respectively; both were lower than the efficiency observed in ultrapure water. As for reaction byproducts, urea phototransformation via UV/VUV yielded nitrate and ammonia as the key products with the mass balance of nitrogen element being met. However, the contents of organic carbon decreased at a rate slightly lower than urea degradation, suggesting that urea was mostly mineralized and slightly converted to unknown organic compounds. The results hence demonstrate that UV/VUV is an effective alternative for urea removal from SPW.
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Affiliation(s)
- Liangchen Long
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China
| | - Yinan Bu
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China
| | - Baiyang Chen
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Rehan Sadiq
- School of Engineering, University of British Columbia Okanagan Campus, Kelowna, BC, V1V1V7, Canada
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33
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Levanov AV, Isaikina OY, Lunin VV. Kinetics and Mechanism of Ozone Interaction with Chloride Ions. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2019. [DOI: 10.1134/s0036024419090103] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Levanov AV, Isaikina OY, Gasanova RB, Uzhel AS, Lunin VV. Kinetics of chlorate formation during ozonation of aqueous chloride solutions. CHEMOSPHERE 2019; 229:68-76. [PMID: 31075704 DOI: 10.1016/j.chemosphere.2019.04.105] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 03/17/2019] [Accepted: 04/14/2019] [Indexed: 06/09/2023]
Abstract
Chlorate ion ClO3- is formed as a result of the complex chemical interaction of ozone with chloride ion in aqueous solution. In neutral and basic solutions, chlorate is the main product. In acid solutions, the main product is molecular chlorine Cl2, and the yield of chlorate is 50-100 times lower. Dependencies have been studied of chlorate formation rate on significant experimental factors: concentrations of initial substances, ozone and chloride ion, acidity (pH), ionic strength and temperature of the reaction solution. The kinetic laws of chlorate generation have been established, and the expressions are given for rate constants of chlorate formation as functions of temperature and ionic strength. When tert-butanol is added to the reaction system, the formation of chlorate ceases, which is an evidence of the crucial role of free radical reactions in this process.
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Affiliation(s)
- Alexander V Levanov
- Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskiye Gory 1, Building 3, 119991, Moscow, Russia.
| | - Oksana Ya Isaikina
- Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskiye Gory 1, Building 3, 119991, Moscow, Russia
| | - Ramiya B Gasanova
- Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskiye Gory 1, Building 3, 119991, Moscow, Russia
| | - Anna S Uzhel
- Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskiye Gory 1, Building 3, 119991, Moscow, Russia
| | - Valery V Lunin
- Department of Chemistry, M.V. Lomonosov Moscow State University, Leninskiye Gory 1, Building 3, 119991, Moscow, Russia
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Liu Z, Ding H, Zhao C, Wang T, Wang P, Dionysiou DD. Electrochemical activation of peroxymonosulfate with ACF cathode: Kinetics, influencing factors, mechanism, and application potential. WATER RESEARCH 2019; 159:111-121. [PMID: 31082642 DOI: 10.1016/j.watres.2019.04.052] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/15/2019] [Accepted: 04/27/2019] [Indexed: 06/09/2023]
Abstract
The combination of peroxymonosulfate (PMS) and electrolysis with an activated carbon fiber (ACF) as cathode (E-ACF-PMS) was systematically investigated. A synergistic effect was observed in the E-ACF-PMS process. Compared with the E-ACF-PDS process, the E-ACF-PMS process spent one-third as much energy for elimination of carbamazepine (CBZ). Increased PMS concentration, current density, and pH value significantly enhanced CBZ elimination. It was also noted that the presence of phosphate (PO43-), bicarbonate (HCO3-), and humic acid (HA) inhibited CBZ removal, while the presence of chloride ion (Cl-) accelerated it. According to radical scavenging experiments and the estimation of relative contribution, reactive oxygen species oxidation (including OH, SO4•-, and 1O2) played an important role in CBZ degradation, accounting for 75.67%. We systematically explored the production mechanism for 1O2 and the results demonstrated that 1O2 was mainly generated on the cathode, rather than generated by O2•- or O2 reported by other researchers. Possible degradation pathways for CBZ in E-ACF-PMS process were also proposed. Finally, the potential for practical applications was explored and compared with E-ACF-PDS. The results of SEM images, BET, and nitrogen adsorption isotherm before and after ACF reuse for 50 times suggested that ACF could maintain its adsorption capacity and catalytic ability in the E-ACF-PMS process. Testing also suggested that the protection of ACF in electrochemical oxidation was based on its relatively high current intensity and removal efficiency. The removal efficiencies of other organic pollutants, including nitrobenzene (NB), sulfamethoxazole (SMX), diclofenac (DC), and tetracycline (TC) were also evaluated. In addition, experiments were conducted to study the effects of different water matrices and toxicology implications and results demonstrated that substituting PMS for PDS in an E-ACF system could create a more efficient, sustainable, and with less secondary toxicity process for wastewater treatment.
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Affiliation(s)
- Zhen Liu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (ChEE), University of Cincinnati, Cincinnati, OH, 45221-0071, USA
| | - Haojie Ding
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China
| | - Chun Zhao
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China.
| | - Tuo Wang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, PR China; Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China
| | - Pu Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (ChEE), University of Cincinnati, Cincinnati, OH, 45221-0071, USA.
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36
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Wang Z, Chen G, Patton S, Ren C, Liu J, Liu H. Degradation of nitrilotris-methylenephosphonic acid (NTMP) antiscalant via persulfate photolysis: Implications on desalination concentrate treatment. WATER RESEARCH 2019; 159:30-37. [PMID: 31078749 DOI: 10.1016/j.watres.2019.04.051] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/22/2019] [Accepted: 04/27/2019] [Indexed: 06/09/2023]
Abstract
Nitrilotris-methylenephosphonic acid (NTMP) has been widely used as an antiscalant in reverse osmosis (RO) desalination and other industrial processes to inhibit scaling from calcium and other hardness ions. Removal of NTMP from RO concentrate can induce the precipitation of oversaturated scale-forming substances, enable additional water recovery from RO concentrate, and reduce the risk of eutrophication after brine disposal. This study investigated the kinetics and mechanisms of oxidative degradation of NTMP by UV photolysis of persulfate at 254 nm. Results showed that NTMP was effectively degraded by persulfate photolysis and the reaction followed pseudo first-order kinetics. The degradation of NTMP was favorable at circumneutral pHs but significantly inhibited in highly alkaline conditions (e.g., pH of 11.5), mainly due to the reduced concentration of SO4•-. Using a competition reaction kinetics approach, the second-order rate constants of NTMP with SO4•- and HO• were determined to be (2.9 ± 0.6) × 107 M-1s-1 and (1.1 ± 0.1) × 108 M-1s-1, respectively. SO4•- had a predominant contribution to NTMP degradation (62%-95%), because the steady-state concentration of SO4•- was 11-54 times higher than that of HO• at pHs between 4 and 11.5. NTMP degradation rate increased with an increase in persulfate dosage and a decrease in NTMP concentration. In the real RO concentrate, NTMP degradation rate was impacted by the presence of chloride and bicarbonate. The degradation of NTMP started with the cleavage of C-N bonds, and then generated intermediates including iminodi(methylene)phosphonate, hydroxymethylphosphonic acid and aminotris(methylenephosphonic acid), which were eventually mineralized into ammonia, phosphate and carbon dioxide. This study demonstrated that UV/persulfate is a promising technology to remove phosphonate antiscalants from RO concentrate.
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Affiliation(s)
- Zhi Wang
- Key Laboratory for Environment and Disaster Monitoring and Evaluation, Hubei, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan, 430077, China; Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Gongde Chen
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Samuel Patton
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Changxu Ren
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Jinyong Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA
| | - Haizhou Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, 92521, USA.
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Troian-Gautier L, Turlington MD, Wehlin SAM, Maurer AB, Brady MD, Swords WB, Meyer GJ. Halide Photoredox Chemistry. Chem Rev 2019; 119:4628-4683. [PMID: 30854847 DOI: 10.1021/acs.chemrev.8b00732] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Halide photoredox chemistry is of both practical and fundamental interest. Practical applications have largely focused on solar energy conversion with hydrogen gas, through HX splitting, and electrical power generation, in regenerative photoelectrochemical and photovoltaic cells. On a more fundamental level, halide photoredox chemistry provides a unique means to generate and characterize one electron transfer chemistry that is intimately coupled with X-X bond-breaking and -forming reactivity. This review aims to deliver a background on the solution chemistry of I, Br, and Cl that enables readers to understand and utilize the most recent advances in halide photoredox chemistry research. These include reactions initiated through outer-sphere, halide-to-metal, and metal-to-ligand charge-transfer excited states. Kosower's salt, 1-methylpyridinium iodide, provides an early outer-sphere charge-transfer excited state that reports on solvent polarity. A plethora of new inner-sphere complexes based on transition and main group metal halide complexes that show promise for HX splitting are described. Long-lived charge-transfer excited states that undergo redox reactions with one or more halogen species are detailed. The review concludes with some key goals for future research that promise to direct the field of halide photoredox chemistry to even greater heights.
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Affiliation(s)
- Ludovic Troian-Gautier
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Michael D Turlington
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Sara A M Wehlin
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Andrew B Maurer
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Matthew D Brady
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Wesley B Swords
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
| | - Gerald J Meyer
- Department of Chemistry , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States
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38
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Wu CH, Kuo CY, Dong CD, Chen CW, Lin YL. Removal of sulfonamides from wastewater in the UV/TiO 2 system: effects of pH and salinity on photodegradation and mineralization. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 79:349-355. [PMID: 30865606 DOI: 10.2166/wst.2019.053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The effects of salinity on the photodegradation and mineralization of sulfonamides in the UV/TiO2 system were investigated. The goals of this study were to analyze the effects of pH and salinity on the sulfonamide concentration and total organic carbon (TOC) during the removal of sulfonamides in a UV/TiO2 system. Four sulfonamides - sulfadiazine (SDZ), sulfamethizole (SFZ), sulfamethoxazole (SMX) and sulfathiazole (STZ) - were selected as parent compounds. The photodegradation and mineralization rates of sulfonamides in the UV/TiO2 system satisfy pseudo-first-order kinetics. Direct photolysis degraded sulfonamides but sulfonamides cannot be mineralized. The photodegradation and mineralization rate constants in all experiments followed the order pH 5 > pH 7 > pH 9. At pH 5, the mineralization rate constants of SMX, SFZ, SDZ and STZ were 0.015, 0.009, 0.012 and 0.011 min-1, respectively. The addition of NaCl inhibited the mineralization of the four tested sulfonamides more than it inhibited their photodegradation. The inhibitory effect of chloride ions on the removal of sulfonamides in the UV/TiO2 system was attributed to the scavenging by chloride ions of hydroxyl radicals (HO•) and holes and the much lower reactivity of chlorine radicals thus formed, even though the chlorine radicals were more abundant than HO•.
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Affiliation(s)
- C H Wu
- Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan E-mail:
| | - C Y Kuo
- Department of Environmental and Safety Engineering, National Yunlin University of Science and Technology, Yunlin, Taiwan
| | - C D Dong
- Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan E-mail:
| | - C W Chen
- Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan E-mail:
| | - Y L Lin
- Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan E-mail:
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Lallement A, Vinatier V, Brigante M, Deguillaume L, Delort AM, Mailhot G. First evaluation of the effect of microorganisms on steady state hydroxyl radical concentrations in atmospheric waters. CHEMOSPHERE 2018; 212:715-722. [PMID: 30179836 DOI: 10.1016/j.chemosphere.2018.08.128] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
Clouds are complex multiphasic media where efficient chemical reactions take place and where microorganisms have been found to be metabolically active. Hydroxyl radical is the main oxidant in cloud water, and more generally in the atmosphere, during the day and drives the cloud oxidative capacity. However, only one measurement of the steady state hydroxyl radical concentrations in cloud water has been reported so far. Cloud chemistry models are used to estimate the hydroxyl radical concentrations with values ranging from 10-12 to 10-15 M that are surely overestimated due to a lack of knowledge about the speciation of the organic matter acting as a sink for hydroxyl radicals. The aim of this work is to quantify the concentration of hydroxyl radicals at steady state in rain and cloud waters and to measure the impact of native microflora on this concentration. First, the non-toxicity of terephthalic acid as probe is controlled before the analysis in real atmospheric water samples. Higher concentrations of hydroxyl radicals are found in cloud waters than in rain waters, with a mean value "1.6 ± 1.5" × 10-16 M and "7.2 ± 5.0" × 10-16 M for rain and cloud waters respectively and no real impact of microorganisms was observed. This method allows the measurement of steady state hydroxyl radical levels at very low concentrations (down to 10-17 M) and it is biocompatible, fast and easy to handle. It is a useful tool, complementary to other methods, to give a better overview of atmospheric water oxidant capacity.
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Affiliation(s)
- A Lallement
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - V Vinatier
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - M Brigante
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France
| | - L Deguillaume
- Université Clermont Auvergne, CNRS, Laboratoire de Météorologie Physique, 63000, Clermont-Ferrand, France
| | - A M Delort
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France.
| | - G Mailhot
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, 63000, Clermont-Ferrand, France.
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40
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Rodrigues CJ, Bobb JA, John MG, Fisenko SP, El-Shall MS, Tibbetts KM. Nucleation and growth of gold nanoparticles initiated by nanosecond and femtosecond laser irradiation of aqueous [AuCl 4] . Phys Chem Chem Phys 2018; 20:28465-28475. [PMID: 30411753 PMCID: PMC6310131 DOI: 10.1039/c8cp05774e] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Irradiation of aqueous [AuCl4]- with 532 nm nanosecond (ns) laser pulses produces monodisperse (PDI = 0.04) 5 nm Au nanoparticles (AuNPs) without any additives or capping agents via a plasmon-enhanced photothermal autocatalytic mechanism. Compared with 800 nm femtosecond (fs) laser pulses, the AuNP growth kinetics under ns laser irradiation follow the same autocatalytic rate law, but with a significantly lower sensitivity to laser pulse energy. The results are explained using a simple model for simulating heat transfer in liquid water and at the interface with AuNPs. While the extent of water superheating with the ns laser is smaller compared to the fs laser, its significantly longer duration can provide sufficient energy to dissociate a small fraction of the [AuCl4]- present, resulting in the formation of AuNPs by coalescence of the resulting Au atoms. Irradiation of initially formed AuNPs at 532 nm results in plasmon-enhanced superheating of water, which greatly accelerates the rate of thermal dissociation of [AuCl4]- and accounts for the observed autocatalytic kinetics. The plasmon-enhanced heating under ns laser irradiation fragments the AuNPs and results in nearly uniform 5 nm particles, while the lack of particles' heating under fs laser irradiation results in the growth of the particles as large as 40 nm.
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Affiliation(s)
- Collin J. Rodrigues
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Julian A. Bobb
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Mallory G. John
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Sergey P. Fisenko
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA
- A.V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 220072 Minsk, Belarus
| | - M. Samy El-Shall
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284, USA
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41
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Bu Y, Song M, Han J, Zhang Z, Chen B, Zhang X, Yang M. A facile and green pretreatment method for nonionic total organic halogen (NTOX) analysis in water - Step II. Using photolysis to convert NTOX completely into halides. WATER RESEARCH 2018; 145:579-587. [PMID: 30199802 DOI: 10.1016/j.watres.2018.08.056] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/21/2018] [Accepted: 08/25/2018] [Indexed: 06/08/2023]
Abstract
Adsorbable organic halogen (AOX) is a parameter conventionally used to indicate the sum of organic halogenated disinfection byproducts (DBPs), which are formed from the reactions of disinfectants with dissolved organic matter, bromide and iodide in water. To overcome the issues of the AOX analytical method, we proposed a new facile and green pretreatment method to enable the analysis of nonionic total organic halogen (NTOX) via the following three steps: 1) separation of NTOX and halides with electrodialysis, 2) conversion of NTOX with ultraviolet (UV) photolysis, and 3) analysis of halides with ion chromatography. To verify this proposal, we mainly evaluated the efficiency of vacuum ultraviolet (VUV) coupled with UV photolysis (VUV-UV) in converting NTOX into halides. Results showed that by applying VUV irradiation for 60 min and UV irradiation at pH 10-11 for another 30 min, over 85.5% of each halide from 20 representative small molecular weight DBPs (each at 100 μg-X/L level) was recovered. The purpose of UV photolysis under alkaline conditions was to reduce oxyhalides (such as bromate and iodate) formed in the VUV process back to halides. With the aid of electrospray ionization-triple quadrupole mass spectrometry, we captured the whole pictures of high molecular weight polar DBPs in a chlorinated drinking water before and after VUV-UV, through which averagely 96.4% of dehalogenation with the VUV-UV treatment was observed. An illustrative comparison of the conventional AOX method and the proposed NTOX method indicates that although the detected NTOX was lower (by 2.3-30.6%) than AOX, the results of the two methods were highly correlated (R2 > 0.97). All these hence verified the photolysis as a mature yet novel tool for sample pretreatment in environmental analytical chemistry.
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Affiliation(s)
- Yinan Bu
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Mingrui Song
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Shenzhen, 518055, China
| | - Jiarui Han
- Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Zhenxuan Zhang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, China
| | - Baiyang Chen
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Xiangru Zhang
- Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China
| | - Mengting Yang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, China.
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Yi R, Hongo Y, Yoda I, Adam ZR, Fahrenbach AC. Radiolytic Synthesis of Cyanogen Chloride, Cyanamide and Simple Sugar Precursors. ChemistrySelect 2018. [DOI: 10.1002/slct.201802242] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ruiqin Yi
- Earth-Life Science Institute; Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku; Tokyo 152-8550 Japan
| | - Yayoi Hongo
- Earth-Life Science Institute; Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku; Tokyo 152-8550 Japan
| | - Isao Yoda
- Co-60 Radiation Facility; Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku; Tokyo 152-8550 Japan
| | - Zachary R. Adam
- Department of Earth and Planetary Sciences; Harvard University; Cambridge, MA USA
- Blue Marble Space Institute of Science; Seattle, WA USA
| | - Albert C. Fahrenbach
- Earth-Life Science Institute; Tokyo Institute of Technology 2-12-1-IE-1 Ookayama, Meguro-ku; Tokyo 152-8550 Japan
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43
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Zhang K, Parker KM. Halogen Radical Oxidants in Natural and Engineered Aquatic Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:9579-9594. [PMID: 30080407 DOI: 10.1021/acs.est.8b02219] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Photochemical reactions contribute to the transformation of contaminants and biogeochemically important substrates in environmental aquatic systems. Recent research has demonstrated that halogen radicals (e.g., Cl•, Br•, Cl2•-, BrCl•-, Br2•-) impact photochemical processes in sunlit estuarine and coastal waters rich in halides (e.g., chloride, Cl-, and bromide, Br-). In addition, halogen radicals participate in contaminant degradation in some engineered processes, including chlorine photolysis for drinking water treatment and several radical-based processes for brine and wastewater treatment. Halogen radicals react selectively with substrates (with bimolecular rate constants spanning several orders of magnitude) and via several potential chemical mechanisms. Consequently, their role in photochemical processes remains challenging to assess. This review presents an integrative analysis of the chemistry of halogen radicals and their contribution to aquatic photochemistry in sunlit surface waters and engineered treatment systems. We evaluate existing data on the generation, speciation, and reactivity of halogen radicals, as well as experimental and computational approaches used to obtain this data. By evaluating existing data and identifying major uncertainties, this review provides a basis to assess the impact of halogen radicals on photochemical processes in both saline surface waters and engineered treatment systems.
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Affiliation(s)
- Ke Zhang
- Department of Energy, Environmental & Chemical Engineering , Washington University in St. Louis , Brauer Hall, 1 Brookings Dr. , St Louis , Missouri 63130 , United States
| | - Kimberly M Parker
- Department of Energy, Environmental & Chemical Engineering , Washington University in St. Louis , Brauer Hall, 1 Brookings Dr. , St Louis , Missouri 63130 , United States
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44
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Li W, Patton S, Gleason JM, Mezyk SP, Ishida KP, Liu H. UV Photolysis of Chloramine and Persulfate for 1,4-Dioxane Removal in Reverse-Osmosis Permeate for Potable Water Reuse. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:6417-6425. [PMID: 29653056 DOI: 10.1021/acs.est.7b06042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A sequential combination of membrane treatment and UV-based advanced oxidation processes (UV/AOP) has become the industry standard for potable water reuse. Chloramines are used as membrane antifouling agents and therefore carried over into the UV/AOP. In addition, persulfate (S2O82-) is an emerging oxidant that can be added into a UV/AOP, thus creating radicals generated from both chloramines and persulfate for water treatment. This study investigated the simultaneous photolysis of S2O82- and monochloramine (NH2Cl) on the removal of 1,4-dioxane (1,4-D) for potable-water reuse. The dual oxidant effects of NH2Cl and S2O82- on 1,4-D degradation were examined at various levels of oxidant dosage, chloride, and solution pH. Results showed that a NH2Cl-to-S2O82- molar ratio of 0.1 was optimal, beyond which the scavenging by NH2Cl of HO•, SO4•-, and Cl2•- radicals decreased the 1,4-D degradation rate. At the optimal ratio, the degradation rate of 1,4-D increased linearly with the total oxidant dose up to 6 mM. The combined photolysis of NH2Cl and S2O82- was sensitive to the solution pH due to a disproportionation of NH2Cl at pH lower than 6 into less-photoreactive dichloramine (NHCl2) and radical scavenging by NH4+. The presence of chloride transformed HO• and SO4•- to Cl2•- that is less-reactive with 1,4-D, while the presence of dissolved O2 promoted gaseous nitrogen production. Results from this study suggest that the presence of chloramines can be beneficial to persulfate photolysis in the removal of 1,4-D; however, the treatment efficiency depends on a careful control of an optimal NH2Cl dosage and a minimal chloride residue.
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Affiliation(s)
| | | | - Jamie M Gleason
- Department of Chemistry and Biochemistry , California State University , Long Beach , California 90840 , United States
| | - Stephen P Mezyk
- Department of Chemistry and Biochemistry , California State University , Long Beach , California 90840 , United States
| | - Kenneth P Ishida
- Research & Development Department , Orange County Water District , Fountain Valley , California 92708 , United States
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45
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Fu X, Dionysiou DD, Brusseau ML, Zaman WQ, Zang X, Lu S, Qiu Z, Sui Q. Enhanced effect of EDDS and hydroxylamine on Fe(II)-catalyzed SPC system for trichloroethylene degradation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:15733-15742. [PMID: 29574649 PMCID: PMC6038806 DOI: 10.1007/s11356-018-1708-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 03/07/2018] [Indexed: 05/04/2023]
Abstract
This study presents a performance comparison of Fe(II)-catalyzed sodium percarbonate (SPC), Fe(II)-EDDS-catalyzed SPC, and of the innovative hydroxylamine hydrochloride (HA)-Fe(II)-EDDS-catalyzed SPC for the degradation of trichloroethylene (TCE) in water. TCE degradation was greater in the Fe(II)-EDDS-catalyzed SPC system compared to the Fe(II)-catalyzed SPC system, indicating the effectiveness of adding EDDS as an enhancement factor for the removal of TCE. Moreover, TCE degradation was faster in the HA-Fe(II)-EDDS-catalyzed SPC system compared to the Fe(II)-EDDS-catalyzed SPC system, illustrating that HA can play a synergistic role in TCE degradation. Analysis of iron distribution in the three systems demonstrated that EDDS addition maintained iron in soluble form, and that the generation of soluble ferrous from ferric iron was expedited with addition of HA. Studies using nitrobenzene and carbon tetrachloride probes provided insights on the generation of hydroxyl radical (HO•) and superoxide anion radical (O2•-) in the three systems. A gradual increasing contribution of O2•- to TCE removal in Fe(II)-catalyzed SPC, Fe(II)-EDDS-catalyzed SPC, and HA-Fe(II)-EDDS-catalyzed SPC systems was verified through free-radical scavenger tests. Finally, monitoring of Cl- concentrations manifested the complete dechlorination of TCE. A possible mechanism of TCE degradation involving two pathways of HO• oxidation and O2•- reaction was proposed.
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Affiliation(s)
- Xiaori Fu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), College of Engineering and Applied Science, University of Cincinnati, Cincinnati, OH, 45221-0012, USA
| | - Mark L Brusseau
- Soil, Water and Environmental Science Department, School of Earth and Environmental Sciences, The University of Arizona, 429 Shantz Bldg, Tucson, AZ, 85721, USA
| | - Waqas Qamar Zaman
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Xueke Zang
- Shanghai Institute of Geological Engineering Exploration, Shanghai, 200072, China.
| | - Shuguang Lu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China.
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
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Moser PB, Ricci BC, Alvim CB, Cerqueira ACF, Amaral MCS. Removal of organic matter of electrodialysis reversal brine from a petroleum refinery wastewater reclamation plant by UV and UV/H 20 2 process. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2018; 53:430-435. [PMID: 29206081 DOI: 10.1080/10934529.2017.1409580] [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] [Indexed: 06/07/2023]
Abstract
Direct (UV) and hydrogen peroxide-assisted (UV/H2O2) photolysis were investigated in bench-scale for removing the organic compounds present in the electrodialysis reversal (EDR) brine from a refinery wastewater reclamation plant. In the UV/H2O2 experiments, a COD:H2O2 molar ratios of 1:1, 1:2 and 1:3 were tested by recirculating the brine in the UV reactor for 120 min. Results showed a significant reduction in UVA254, whereas no reduction was observed for chemical oxygen demand (COD), in the UV process, suggesting great cleavage but limited mineralization of the organic matter. UV/H2O2 with C:H2O2 ratio of 1:3 exhibited high efficiency in removing the organic matter (COD removal of 92% with an electrical energy per removal order (EEO) value of 22 kW h m-3). Although the EDR brine has high salinity, no strong scavenging effect of •OH was found in the water matrix due to the high concentration of anions, especially chloride and bicarbonate. Finally, UV/H2O2 with C:H2O2 ratio of 1:3 and residence time of 120 min is an efficient alternative for organic matter removal of EDR brine from refinery wastewater reclamation plant showing total capital cost (CapEx) estimated at US$ 369,653.00 and total operational cost (OpEx), at US$ 1.772 per cubic meter of effluent.
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Affiliation(s)
- Priscila B Moser
- a Department of Sanitary and Environmental Engineering , Federal University of Minas Gerais , Belo Horizonte , Brazil
| | - Bárbara C Ricci
- a Department of Sanitary and Environmental Engineering , Federal University of Minas Gerais , Belo Horizonte , Brazil
| | - Clara B Alvim
- a Department of Sanitary and Environmental Engineering , Federal University of Minas Gerais , Belo Horizonte , Brazil
| | - Ana C F Cerqueira
- a Department of Sanitary and Environmental Engineering , Federal University of Minas Gerais , Belo Horizonte , Brazil
| | - Míriam C S Amaral
- a Department of Sanitary and Environmental Engineering , Federal University of Minas Gerais , Belo Horizonte , Brazil
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47
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Xie T, Hu H, Chen D, Sun P. Electrochemical Degradation of Tetracycline Hydrochloride in Aqueous Medium by (B4
C/C)-β-PbO2
Electrode. B KOREAN CHEM SOC 2017. [DOI: 10.1002/bkcs.11166] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Tingting Xie
- School of Chemical and Environmental Engineering; Shanghai Institute of Technology; Shanghai 201418 China
| | - Hongtao Hu
- School of Chemical and Environmental Engineering; Shanghai Institute of Technology; Shanghai 201418 China
| | - Donghui Chen
- School of Chemical and Environmental Engineering; Shanghai Institute of Technology; Shanghai 201418 China
| | - Pengzhe Sun
- School of Chemical and Environmental Engineering; Shanghai Institute of Technology; Shanghai 201418 China
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48
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Boutiti A, Zouaghi R, Bendjabeur SE, Guittonneau S, Sehili T. Photodegradation of 1-hexyl-3-methylimidazolium by UV/H2O2 and UV/TiO2: Influence of pH and chloride. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2016.12.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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49
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Fu X, Gu X, Lu S, Sharma VK, Brusseau ML, Xue Y, Danish M, Fu GY, Qiu Z, Sui Q. Benzene oxidation by Fe(III)-catalyzed sodium percarbonate: matrix constituent effects and degradation pathways. CHEMICAL ENGINEERING JOURNAL (LAUSANNE, SWITZERLAND : 1996) 2017; 309:22-29. [PMID: 28959136 PMCID: PMC5612506 DOI: 10.1016/j.cej.2016.10.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Complete degradation of benzene by the Fe(III)-activated sodium percarbonate (SPC) system is demonstrated. Removal of benzene at 1.0 mM was seen within 160 min, depending on the molar ratios of SPC to Fe(III). A mechanism of benzene degradation was elaborated by free-radical probe-compound tests, free-radical scavengers tests, electron paramagnetic resonance (EPR) analysis, and determination of Fe(II) and H2O2 concentrations. The degradation products were also identified using gas chromatography-mass spectrometry method. The hydroxyl radical (HO.) was the leading species in charge of benzene degradation. The formation of HO. was strongly dependent on the generation of the organic compound radical (R.) and superoxide anion radical (O.). Benzene degradation products included hydroxylated derivatives of benzene (phenol, hydroquinone, benzoquinone, and catechol) and aliphatic acids (oxalic and fumaric acids). The proposed degradation pathways are consistent with radical formation and identified products. The investigation of selected matrix constituents showed that the Cl and HCO3 had inhibitory effects on benzene degradation. Natural organic matter (NOM) had accelerating influence in degrading benzene. The developed system was tested with groundwater samples and it was found that the Fe(III)-activated SPC has a great potential in effective remediation of benzene-contaminated groundwater while more further studies should be done for its practical application in the future because of the complex subsurface environment.
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Affiliation(s)
- Xiaori Fu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaogang Gu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Shuguang Lu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
- Corresponding author: Tel: +86 21 64250709, Fax: +86 21 64252737, (S. Lu)
| | - Virender K. Sharma
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, 1266 TAMU, College Station, Texas 77843, USA
| | - Mark L. Brusseau
- Soil, Water and Environmental Science Department, School of Earth and Environmental Sciences, The University of Arizona, 429 Shantz Bldg., Tucson, AZ 85721, United States
| | - Yunfei Xue
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Muhammad Danish
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - George Y. Fu
- Department of Construction Management & Civil Engineering Technology, Georgia Southern University, Statesboro, GA 30460-8047, United States
| | - Zhaofu Qiu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
| | - Qian Sui
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China
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Zhao Y, Hao R, Xue F, Feng Y. Simultaneous removal of multi-pollutants from flue gas by a vaporized composite absorbent. JOURNAL OF HAZARDOUS MATERIALS 2017; 321:500-508. [PMID: 27669391 DOI: 10.1016/j.jhazmat.2016.09.044] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/18/2016] [Accepted: 09/20/2016] [Indexed: 06/06/2023]
Abstract
An economical process that was used to remove SO2, NO and Hg0 simultaneously was developed, based on the pre-oxidations of Hg0 and NO by a vaporized Fenton-based complex oxidant (FO) consisted of Fenton and NaClO. The effects of concentrations of FeSO4 and NaClO in the oxidant, the molar ratio of vaporized oxidant to multi-pollutant, the oxidant solution pH, the reaction temperature, the gas flow ratio of vaporized FO to multi-pollutants, the flue gas flow and the concentrations of coexistence gases in flue gas on the simultaneous removals were investigated experimentally. The results showed that the removals of NO and Hg0 were significantly depended on FeSO4 and NaClO concentrations, the molar ratio of vaporized oxidant to multi-pollutants, the FO solution pH, the reaction temperature, the gas flow ratio of vaporized FO to multi-pollutants and flue gas flow. And higher concentration of SO2 and an appropriate concentration of NO had the promotion for Hg0 removal. The average simultaneous removal efficiencies of 100% for SO2, 81% for NO and 91% for Hg0 were obtained under the optimal reaction conditions. According to the characterization of the reaction removal products by SEM, EDS, XRD and AFS, the reaction mechanism was speculated.
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Affiliation(s)
- Yi Zhao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China.
| | - Runlong Hao
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
| | - Fangming Xue
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
| | - Yanan Feng
- School of Environmental Science and Engineering, North China Electric Power University, Baoding 071003, PR China
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