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Wang X, Luo Y, Zhang S, Zhou L. Acetylacetone effectively controlled the secondary metabolites of Microcystis aeruginosa under simulated sunlight irradiation. J Environ Sci (China) 2024; 135:285-295. [PMID: 37778804 DOI: 10.1016/j.jes.2022.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/02/2022] [Accepted: 12/03/2022] [Indexed: 10/03/2023]
Abstract
Inactivation of cyanobacterial cells and simultaneous control of secondary metabolites is of significant necessity for the treatment of cyanobacteria-laden water. Acetylacetone (AcAc) has been reported a specific algicide to inactivate Microcystis aeruginosa (M. aeruginosa) and an effective light activator to degrade pollutants. This study systematically investigated the photodegradation ability of AcAc under xenon (Xe) irradiation on the secondary metabolites of M. aeruginosa, mainly algal organic matter (AOM), especially toxic microcystin-LR (MC-LR). Results showed that AcAc outperformed H2O2 in destructing the protein-like substances, humic acid-like matters, aromatic proteins and fulvic-like substances of AOM. For MC-LR (250 µg/L), 0.05 mmol/L AcAc attained the same degradation efficiency (87.0%) as 0.1 mmol/L H2O2. The degradation mechanism of Xe/AcAc might involve photo-induced energy/electron transfer and formation of carbon center radicals. Alkaline conditions (pH > 9.0) were detrimental to the photoactivity of AcAc, corresponding to the observed degradation rate constant (k1 value) of MC-LR drastically decreasing to 0.0013 min-1 as solution pH exceeded 9.0. The PO43- and HCO3- ions had obvious inhibition effects, whereas NO3- slightly improved k1 value from 0.0277 min-1 to 0.0321 min-1. The presence of AOM did not significantly inhibit MC-LR degradation in Xe/AcAc system. In addition, the biological toxicity of MC-LR was greatly reduced after photoreaction. These results demonstrated that AcAc was an alternative algicidal agent to effectively inactivate algal cells and simultaneously control the secondary metabolites after cell lysis. Nevertheless, the concentration and irradiation conditions should be further optimized in practical application.
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Affiliation(s)
- Xiaomeng Wang
- Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
| | - Yixin Luo
- Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Shujuan Zhang
- The State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Lixiang Zhou
- Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
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2
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Magnetic nanoscaled Fe3O4-CeO2-TiO2 composite: UV-Fenton reaction to degrade AO-7 dye. INORG CHEM COMMUN 2023. [DOI: 10.1016/j.inoche.2023.110389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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3
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Copper Nanoparticles Decorated Alginate/Cobalt-Doped Cerium Oxide Composite Beads for Catalytic Reduction and Photodegradation of Organic Dyes. Polymers (Basel) 2022; 14:polym14204458. [PMID: 36298035 PMCID: PMC9612068 DOI: 10.3390/polym14204458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/12/2022] Open
Abstract
Cobalt-doped cerium oxide (Co-CeO2) was synthesized and wrapped inside alginate (Alg) hydrogel beads (Alg/Co-CeO2). Further, copper nanoparticles (Cu) were grown on Alg/Co-CeO2 beads. Cu decorated Alg/Co-CeO2 composite beads (Cu@Alg/Co-CeO2) were tested as a catalyst for the solar-assisted photodegradation and NaBH4-assisted reduction of organic pollutants. Among different dyes, Cu@Alg/Co-CeO2 was found to be the best catalyst for the photodegradation of acridine orange (ArO) under solar light and efficient in reducing methyl orange (MO) with the aid of NaBH4. Cu@Alg/Co-CeO2 decolorized ArO up to 75% in 5 h under solar light, while 97% of MO was reduced in 11 min. The decolorization efficiency of Cu@Alg/Co-CeO2 was further optimized by varying different parameters. Thus, the designed catalyst provides a promising way for efficient oxidation and reduction of pollutants from industrial effluents.
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Gao B, Zhu S, Gu J, Liu Y, Yi X, Zhou H. Superoxide radical mediated Mn(III) formation is the key process in the activation of peroxymonosulfate (PMS) by Mn-incorporated bacterial-derived biochar. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128549. [PMID: 35220118 DOI: 10.1016/j.jhazmat.2022.128549] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/03/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
Biochar was used as a heterogeneous activator for peroxymonosulfate (PMS), and the activation performance strongly depended on the structure, functional groups, and modification of the biochar. In this study, a new type of modified biochar was synthesized by utilizing the Mn(II) adsorption capacity of bacteria. After one-step pyrolysis of Mn(II)-adsorbed bacterial cells at 800 °C, a Mn-incorporated bacterial-derived biochar (Mn-BBC) was successfully produced. It exhibited structural heterogeneity, with MnO located at the surface of the BBC matrix, as shown on the result of SEM and XRD. Compared to BBC, Mn-BBC showed a 10-fold increase (0.0727 min-1 versus 0.0069 min-1) of pollutant removal rate. In addition, it also showed anti-interference capacity against common water matrix (except 10 mM CO32-) and great stability/reusability. Chemical quenching, electron spin resonance, and pyrophosphate trapping indicated an indirect but important role of the superoxide, formed during the self-decomposition of PMS. The MnO on Mn-BBC can be oxidized by superoxide to produce surface Mn(III), which then binds to PMS and forms a surface complex. This complex promotes electron transfer from the pollutant to the Mn-BBC, facilitating the oxidation of the contaminants. Overall, this study confirmed the PMS activation capacity and mechanism of Mn-BBC, which expands the application of BBC-based materials derived from metal-adsorbed microbes.
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Affiliation(s)
- Bixia Gao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Simeng Zhu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Jialiang Gu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Yang Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Xianliang Yi
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Hao Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China.
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5
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Synthesis and Study of Zinc Oxide Nanorods as an Adsorbent Material for the Removal of Carcinogenic Dye and Anticancer Activities. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022. [DOI: 10.1007/s13369-022-06688-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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6
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Zhu S, Xiao P, Wang X, Liu Y, Yi X, Zhou H. Efficient peroxymonosulfate (PMS) activation by visible-light-driven formation of polymorphic amorphous manganese oxides. JOURNAL OF HAZARDOUS MATERIALS 2022; 427:127938. [PMID: 34863569 DOI: 10.1016/j.jhazmat.2021.127938] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/14/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
Heterogeneous sulfate radical-based advanced oxidation processes (SR-AOPs) have been widely reported over the last decade as a promising technology for pollutant removal from wastewater. In this study, a novel peroxymonosulfate (PMS) activator was obtained by visible-light-driven Mn(II) oxidation in the presence of nitrate. The photochemically synthesized manganese oxides (PC-MnOx) were polymorphic amorphous nanoparticles and nanorods, with an average oxidation state of approximately 3.0. It possesses effective PMS activation capacity and can remove 20 mg L-1 acid organic II (AO7) within 30 min. The AO7 removal performance of PC-MnOx was slightly decreased in natural waterbodies and in the presence of CO32-, while it showed an anti-interference capacity for Cl-, NO3- and humic acid. Chemical quenching, reactive oxygen species (ROS) trapping, X-ray photoelectric spectroscopy (XPS), in-situ Raman spectroscopy, and electrochemical experiments supported a nonradical mechanism, i.e., electron transfer from AO7 to the metastable PC-MnOx-PMS complex, which was responsible for AO7 oxidation. The PC-MnOx-PMS system also showed substrate preferences based on their redox potentials. Moreover, PC-MnOx could activate periodate (PI) but not peroxydisulfate (PDS) or H2O2. Overall, this study provides a new catalyst for PMS activation through a mild and green synthesis approach.
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Affiliation(s)
- Simeng Zhu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Pengyu Xiao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Xue Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Yang Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Xianliang Yi
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China
| | - Hao Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology, China.
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Yang F, Sheng B, Wang Z, Xue Y, Liu J, Ma T, Bush R, Kušić H, Zhou Y. Performance of UV/acetylacetone process for saline dye wastewater treatment: Kinetics and mechanism. JOURNAL OF HAZARDOUS MATERIALS 2021; 406:124774. [PMID: 33310333 DOI: 10.1016/j.jhazmat.2020.124774] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Futility of traditional advanced oxidation processes (AOPs) in saline wastewater treatment has stimulated the quest for novel "halotolerant" chemical oxidation technology. Acetylacetone (AA) has proven to be a potent photo-activator in the degradation of dyes, but the applicability of UV/AA for saline wastewater treatment needs to be verified. In this study, degradation of crystal violet (CV) was investigated in the UV/AA system in the presence of various concentrations of exogenic Cl- or Br-. The results reveal that degradation, mineralization and even accumulation of adsorbable organic halides (AOX) were not significantly affected by the addition of Cl- or Br-. Rates of CV degradation were enhanced by elevating either AA dosage or solution acidity. An apparent kinetic rate equation was developed as r = -d[CV]/dt = k[CV]a[AA]b = (7.34 × 10-4 mM1-(a+b) min-1) × [CV]a=0.16 [AA]b=0.97. In terms of results of radical quenching experiments, direct electron/energy transfer is considered as the major reaction mechanism, while either singlet oxygen or triplet state (3(AA)*) might be involved. Based on identification of degradation byproducts, a possible degradation pathway of CV in the UV/AA system is proposed.
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Affiliation(s)
- Fei Yang
- State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Bo Sheng
- State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Zhaohui Wang
- State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, 3663 N. Zhongshan Road, Shanghai 200062, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China.
| | - Ying Xue
- State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Jianshe Liu
- State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Tianyi Ma
- School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Richard Bush
- Sustainable Development Institute, Monash University, Melbourne, Victoria 3800, Australia
| | - Hrvoje Kušić
- Faculty of Chemical Engineering and Technology, University of Zagreb, 10000 Zagreb, Croatia
| | - Yanbo Zhou
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China; 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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Sun Z, Li S, Ding H, Zhu Y, Wang X, Liu H, Zhang Q, Zhao C. Electrochemical/Fe 3+/peroxymonosulfate system for the degradation of Acid Orange 7 adsorbed on activated carbon fiber cathode. CHEMOSPHERE 2020; 241:125125. [PMID: 31683418 DOI: 10.1016/j.chemosphere.2019.125125] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/12/2019] [Accepted: 10/14/2019] [Indexed: 06/10/2023]
Abstract
Acid Orange 7 (AO7), as a most common and widely used synthetic dyes in the printing and dyeing industry, was hardly degradable by traditional wastewater treatment methods. Here, activated carbon fiber (ACF) as an in-situ regenerated cathodic adsorbent in the electrochemical/Fe3+/peroxymonosulfate process (EC/ACF/Fe3+/PMS) was firstly investigated for AO7 removal and compared with several different processes. The results indicated that the effective adsorption of AO7 on ACF can be enhanced under electrolytic conditions, while the adsorbed AO7 on ACF can be completely degraded and mineralized in EC/ACF/Fe3+/PMS process resulting in the in-situ regeneration of ACF. Besides, the electrical energy per order values were investigated, which showed an apparent reduction of electrical energy consumption from 0.42831 to 0.09779 kWh m-3 when ACF-cathode replaced Pt-cathode. Further study revealed that higher conversion rate of Fe2+ from Fe3+ was observed with ACF-cathode. It deserved to be mentioned that the removal efficiency of AO7 was satisfactory and stable even after reusing ACF cathode for 10 times. Furthermore, structure and elements of ACF surface were investigated, which indicated the structure of ACF was intact in EC/ACF/Fe3+/PMS due to inhibition of ACF corrosion by electron migration at cathode. In addition, the total iron content of the effluent in EC/ACF/Fe3+/PMS was lower than that of EC/Fe3+/PMS due to the deposition of iron on ACF-cathode surface. Therefore, advantages of EC/ACF/Fe3+/PMS for AO7 degradation were not only a much higher oxidation efficiency and in-situ regenerated cathodic adsorbent, but also a lower electrical energy consumption and lesser iron ions contents in the effluent.
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Affiliation(s)
- Zhihua Sun
- 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; School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China
| | - Shiyao Li
- 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; School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China
| | - 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
| | - Yunhua Zhu
- 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
| | - Xuxu 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; School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China
| | - Huanfang Liu
- School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China
| | - Qin Zhang
- 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; School of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi, 832003, PR China.
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Liu F, Xu Y, Zhang B, Liu Y, Zhang H. Heterogeneous degradation of organic contaminant by peroxydisulfate catalyzed by activated carbon cloth. CHEMOSPHERE 2020; 238:124611. [PMID: 31524605 DOI: 10.1016/j.chemosphere.2019.124611] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 07/26/2019] [Accepted: 08/17/2019] [Indexed: 06/10/2023]
Abstract
An eco-friendly material, activated carbon cloth (ACC) was used as the heterogeneous catalyst in activation of peroxydisulfate (PDS) for the efficient degradation of organic pollutant in water. Besides, the effects of several parameters in the ACC/PDS process including initial pH, PDS concentration, reaction temperature, stirring speed and co-existing anions were investigated. Under optimum conditions, almost complete removal (98.6%) of AO7 in 60 min and 67.4% of total organic carbon (TOC) removal within 180 min were obtained, accompanied by the remarkable destruction of azo band and naphthalene ring on AO7. The electron paramagnetic resonance and radical quenching experiments were carried out to identify the reactive radicals in the ACC/PDS process. Surface characteristic techniques such as XRD, BET, SEM, FTIR, XPS were applied to analysis the change of crystal structure, surface area, surface morphology, functional groups on the surface of fresh and spent ACC samples. Hydroxyl groups (C‒OH) and π-π transitions significantly affected the catalytic activity of ACC. The intermediate products of AO7 oxidation were identified by LC-MS and the corresponding degradation pathway was proposed.
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Affiliation(s)
- Fuzhen Liu
- Department of Environmental Science and Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan, 430079, China
| | - Yin Xu
- Department of Environmental Science and Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan, 430079, China
| | - Baisong Zhang
- Department of Environmental Science and Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan, 430079, China
| | - Yalu Liu
- Department of Environmental Science and Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan, 430079, China
| | - Hui Zhang
- Department of Environmental Science and Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan, 430079, China.
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10
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Wu S, Liang G, Guan X, Qian G, He Z. Precise control of iron activating persulfate by current generation in an electrochemical membrane reactor. ENVIRONMENT INTERNATIONAL 2019; 131:105024. [PMID: 31357090 DOI: 10.1016/j.envint.2019.105024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/14/2019] [Accepted: 07/15/2019] [Indexed: 06/10/2023]
Abstract
Activated persulfate (PS) oxidation is promising for contaminant removal but a lack of controllable activation can lead to a loss of reagents and thus low contamination degradation. Herein, we have proposed and investigated an innovative method to control PS activation by introducing ion exchange membrane into electrochemically activated PS. This electrochemical membrane reactor (EMR) could precisely control PS activation by adjusting electrical current for slow release of Fe2+, and also avoid direct contact between PS and a sacrificial anode electrode (iron electrode)/an alkaline cathode solution. It was found that the PS decomposition rate constant was linearly increased by increasing the applied current (R2 = 0.988). The rate of the released Fe2+ also exhibited a linear relationship with the applied current (R2 = 0.995). Compared to one-time dosage of Fe2+, the EMR-based slow-release process had higher contamination degradation and better PS utilization (molar ratio of the decomposed PS to the migrated Fe, 1.04 ± 0.01:1), thereby minimizing the waste of both reaction reagents and generated radicals. The EMR was also employed to degrade a representative dye contaminant in a controllable manner and achieved 95.7 ± 0.7% removal percentage with PS dosage of 3.0 g L-1 within 20 min. This study is among the earliest to explore effective approaches for precisely controlling PS activation and subsequent oxidation of contaminants.
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Affiliation(s)
- Simiao Wu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China; Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - Guannan Liang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Xiaohong Guan
- College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Guangren Qian
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Zhen He
- Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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Yang M, Wu B, Li Q, Xiong X, Zhang H, Tian Y, Xie J, Huang P, Tan S, Wang G, Zhang L, Zhang S. Feasibility of the UV/AA process as a pretreatment approach for bioremediation of dye-laden wastewater. CHEMOSPHERE 2018; 194:488-494. [PMID: 29232642 DOI: 10.1016/j.chemosphere.2017.11.155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/22/2017] [Accepted: 11/26/2017] [Indexed: 06/07/2023]
Abstract
Biodegradability and toxicity are two important indexes in considering the feasibility of a chemical process for environmental remediation. The acetylacetone (AA) mediated photochemical process has been proven as an efficient approach for dye decolorization. Both AA and its photochemical degradation products had a high bioavailability. However, the biocompatibility and ecotoxicology of the UV/AA treated solutions are unclear yet. In the present work, we evaluated the biocompatibility and toxicity of the UV/AA treated solutions at both biochemical and organismal levels. The biodegradability of the treated solution was evaluated with the ratio of 5-d biological oxygen demand (BOD5) to chemical oxygen demand (COD) and a 28-d activated sludge assay (Zahn-Wellens tests). The UV/AA process significantly improved the biodegradability of the tested dye solutions. Toxicity was assessed with responses of microorganisms (microbes in activated sludge and Daphnia magna) and plants (bok choy, rice seed, and Arabidopsis thaliana) to the treated solutions, which showed that the toxicity of the UV/AA treated solutions was lower or comparable to that of the UV/H2O2 counterparts. The results are helpful for us to determine whether the UV/AA process is applicable to certain wastewaters and how the UV/AA process could be effectively combined into a sequential chemical-biological water treatment.
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Affiliation(s)
- Minghui Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Qiuhao Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Xiaofeng Xiong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Haoran Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Yu Tian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Jiawen Xie
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Ping Huang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Suo Tan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Guodong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Li Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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12
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Li N, Lu P, He C, Lu W, Chen W. Catalytic degradation of sulfaquinoxalinum by polyester/poly-4-vinylpyridine nanofibers-supported iron phthalocyanine. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:5902-5910. [PMID: 29235030 DOI: 10.1007/s11356-017-0943-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
Iron (II) phthalocyanine (FePc) supported on electrospun polyester/poly-4-vinylpyridine nanofibers (PET/P4VP NFs) was prepared by stirring in tetrahydrofuran. The resulting product was confirmed and characterized by ultraviolet-visible diffuse reflectance spectroscopy, attenuated total reflection Fourier transform infrared spectra, X-ray photoelectron spectroscopy, gas chromatography/mass spectrometry, and ultra-performance liquid chromatography. More than 95% of sulfaquinoxalinum (SQX) could be removed by the activation of hydrogen peroxide in the presence of FePc-P4VP/PET with a PET and P4VP mass ratio of 1:1. This system exhibited a high catalytic activity across a wide pH and temperature range. The degradation rates of SQX achieved 100, 95, and 78% at a pH of 3, 7, and 9, respectively, and the degradation rates of SQX are more than 80% at the temperature ranging from 35 to 65 °C. DMSO2 could be detected by gas chromatography/mass spectrometry after the addition of DMSO, suggesting the formation of the high-valent iron intermediates in this catalytic system. In addition, the electron paramagnetic resonance experiments proved that free radicals did not dominate the reaction in our system. Therefore, the high-valent iron intermediates were proposed to the main active species in the FePc-P4VP/PET/hydrogen peroxide system. In summary, the heterogeneous catalytic processes with non-radical catalytic mechanism might have better catalytic performance for the removal of organic pollutants, which can potentially be used in wastewater treatment.
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Affiliation(s)
- Nan Li
- National Engineering Laboratory for Textile Fiber Materials & Processing Technology (Zhejiang), Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Panting Lu
- National Engineering Laboratory for Textile Fiber Materials & Processing Technology (Zhejiang), Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Cuixia He
- National Engineering Laboratory for Textile Fiber Materials & Processing Technology (Zhejiang), Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Wangyang Lu
- National Engineering Laboratory for Textile Fiber Materials & Processing Technology (Zhejiang), Zhejiang Sci-Tech University, Hangzhou, 310018, China.
| | - Wenxing Chen
- National Engineering Laboratory for Textile Fiber Materials & Processing Technology (Zhejiang), Zhejiang Sci-Tech University, Hangzhou, 310018, China
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Zhang C, Sun Y, Yu Z, Zhang G, Feng J. Simultaneous removal of Cr(VI) and acid orange 7 from water solution by dielectric barrier discharge plasma. CHEMOSPHERE 2018; 191:527-536. [PMID: 29059560 DOI: 10.1016/j.chemosphere.2017.10.087] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/25/2017] [Accepted: 10/14/2017] [Indexed: 06/07/2023]
Abstract
A feasibility study was conducted for simultaneous removal of hexavalent chromium (Cr(VI)) and azo dye acid orange 7 (AO7) by the dielectric barrier discharge (DBD) plasma. The results showed that there was a synergistic effect between Cr(VI) reduction and AO7 degradation. The presence of Cr(VI) enhanced the degradation efficiency of AO7. Meanwhile, the removal efficiency of Cr(VI) also increased in the presence of AO7. Under acidic conditions (pH = 3.0), the reduction efficiency of Cr(VI) was higher (approximately 94%). However, the presence of Cr(VI) diminished the effect of pH on the AO7 degradation efficiency. By increasing the input voltage from 80 to 120 V, the removal efficiencies of Cr(VI) and AO7 were observably increased from 54% to 88% and 62% to 89%, respectively. Adding organic matters inhibited the degradation of AO7 and promoted the reduction of Cr(VI). The addition of Cu(II), Co(II), Ni(II), Mn(II) and Fe(III) could inhibit the Cr(VI) reduction, but not significantly affect the degradation of AO7. The degradation intermediates of AO7 were identified by LC-MS/MS system and a possible degradation pathway was proposed. This study showed that the DBD plasma can simultaneously remove Cr(VI) and AO7, which provided a new idea for the actual wastewater treatment.
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Affiliation(s)
- Chunxiao Zhang
- State Key Laboratory of Pollution Control & Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Yabing Sun
- State Key Laboratory of Pollution Control & Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
| | - Zhongqing Yu
- State Key Laboratory of Pollution Control & Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Guyu Zhang
- State Key Laboratory of Pollution Control & Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Jingwei Feng
- Department of Municipal Engineering, School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei 230009, PR China.
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Xu Y, Lin H, Li Y, Zhang H. The mechanism and efficiency of MnO 2 activated persulfate process coupled with electrolysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 609:644-654. [PMID: 28763661 DOI: 10.1016/j.scitotenv.2017.07.151] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/14/2017] [Accepted: 07/17/2017] [Indexed: 06/07/2023]
Abstract
Pure three-dimensional manganese oxides (MnO2) were successfully synthesized by a simple one-step hydrothermal process. The obtained particles were characterized via XRD, BET, SEM, XPS and FTIR techniques. To enhance the efficiency of heterogeneous catalytic process, a facile and effective electrochemical method was introduced. The degradation of C. I. Acid Orange 7 (AO7) as the target pollutant in aqueous solution by an oxidation system involving MnO2 activated peroxydisulfate (PDS) coupled with electrochemical method is reported herein. Influences of some key reaction parameters such as initial pH (pH0), current density, initial AO7 concentration, dosage of MnO2 and anions (Cl-, NO3-, HCO3- and H2PO4-) were investigated. The cyclic voltammetry (CV) was performed to investigate the charge transfer process occurred at the surface of catalyst. LC-MS/MS analysis was applied to identify degradation intermediates and a plausible degradation mechanism is proposed accordingly. Activated sludge inhibition tests were carried out to evaluate the change of toxicity of the dye solution in the oxidation process. The inorganic by-products such as NO2-, NO3-, and NH4+ along with AO7 degradation were also identified. The stability of MnO2 catalyst was evaluated by recycling experiments and the electrical energy consumption was also investigated. Radical quenching tests with several scavengers (methanol, tert-butyl alcohol, 1,4-benzoquinone and phenol) were performed to clarify the dominating reactive species participating in this oxidation process and the underlying mechanisms involving the generation of radical from the proposed electro-assisted heterogeneous activated PDS system were identified.
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Affiliation(s)
- Yin Xu
- Department of Environmental Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan 430079, China; Shenzhen Research Institute of Wuhan University, Shenzhen 518057, China
| | - Heng Lin
- Department of Environmental Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan 430079, China; Shenzhen Research Institute of Wuhan University, Shenzhen 518057, China
| | - Yukun Li
- Department of Environmental Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan 430079, China
| | - Hui Zhang
- Department of Environmental Engineering, Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan University, Wuhan 430079, China; Shenzhen Research Institute of Wuhan University, Shenzhen 518057, China.
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Synthesis, Structure, and Dye Adsorption Properties of a Nickel(II) Coordination Layer Built from d-Camphorate and Bispyridyl Ligands. Polymers (Basel) 2017; 9:polym9120661. [PMID: 30965961 PMCID: PMC6418792 DOI: 10.3390/polym9120661] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 11/26/2017] [Accepted: 11/28/2017] [Indexed: 11/16/2022] Open
Abstract
Reaction of NiCl₂∙6H₂O, d-camphoric acid (d-H₂cam), and N,N'-bis(pyraz-2-yl)piperazine (bpzpip) in pure water at 150 °C afforded a novel nickel(II) coordination layer, [Ni₄(d-cam)₂(d-Hcam)₄(bpzpip)₄(H₂O)₂] (1), under hydro(solvo)thermal conditions. Single-crystal X-ray structure analysis reveals that 1 adopts a six-connected two-dimensional (2D) chiral layer structure with 3⁶-hxl topology. Dye adsorption explorations indicate that 1 readily adsorbs methyl blue (MyB) from water without destruction of crystallinity. On the contrary, methyl orange (MO) is not adsorbed at all. The pseudo-second-order kinetic model could be used to interpret the adsorption kinetics for MyB. Equilibrium isotherm studies suggest complicated adsorption processes for MyB which do not have good applicability for either the two-parameter Langmuir or Freundlich isotherm model. The saturated adsorption capacity of 1 for MyB calculated by Langmuir is 185.5 mg·g-1 at room temperature.
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Wu B, Yang M, Yin R, Zhang S. Applicability of light sources and the inner filter effect in UV/acetylacetone and UV/H 2O 2 processes. JOURNAL OF HAZARDOUS MATERIALS 2017; 335:100-107. [PMID: 28432968 DOI: 10.1016/j.jhazmat.2017.04.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/11/2017] [Accepted: 04/03/2017] [Indexed: 06/07/2023]
Abstract
Light source is a crucial factor in the application of a photochemical process, which determines the energy efficiency. The performances of acetylacetone (AA) in conversion of aqueous contaminants under irradiation with a low-pressure mercury lamp, a medium-pressure mercury lamp, a xenon lamp, and natural sunlight were investigated and compared with those of H2O2 as reference. In all cases, AA was superior to H2O2 in the degradation of Acid Orange 7. Using combinations of the different light sources with various cut-off and band-pass filters, the spectra responses of the absorbed photons in the UV/AA and UV/H2O2 processes were determined for two colored and two colorless compounds. The photonic efficiency (φ) of the two photochemical processes was found to be target-dependent. A calculation approach for the inner filter effect was developed by taking the obtained φ into account, which provides a more accurate indication of the reaction mechanisms.
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Affiliation(s)
- Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Minghui Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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17
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Levels of Organic Pollution Indicators in Groundwater at the Old Landfill and Waste Management Site. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7060638] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Zhang G, Wu B, Zhang S. Effects of acetylacetone on the photoconversion of pharmaceuticals in natural and pure waters. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 225:691-699. [PMID: 28400150 DOI: 10.1016/j.envpol.2017.01.089] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 01/07/2017] [Accepted: 01/09/2017] [Indexed: 06/07/2023]
Abstract
Acetylacetone (AcAc) has proven to be a potent photo-activator in the degradation of color compounds. The effects of AcAc on the photochemical conversion of five colorless pharmaceuticals were for the first time investigated in both pure and natural waters with the UV/H2O2 process as a reference. In most cases, AcAc played a similar role to H2O2. For example, AcAc accelerated the photodecomposition of carbamazepine, oxytetracycline, and tetracycline in pure water. Meanwhile, the toxicity of tetracyclines and carbamazepine were reduced to a similar extent to that in the UV/H2O2 process. However, AcAc worked in a way different from that of H2O2. Based on the degradation kinetics, solvent kinetic isotope effect, and the inhibiting effect of O2, the underlying mechanisms for the degradation of pharmaceuticals in the UV/AcAc process were believed mainly to be direct energy transfer from excited AcAc to pharmaceuticals rather than reactive oxygen species-mediated reactions. In natural waters, dissolved organic matter (DOM) played a crucial role in the photoconversion of pharmaceuticals. The role of H2O2 became negligible due to the scavenging effects of DOM and inorganic ions. Interestingly, in natural waters, AcAc first accelerated the photodecomposition of pharmaceuticals and then led to a dramatic reduction with the depletion of dissolved oxygen. Considering the natural occurrence of diketones, the results here point out a possible pathway in the fate and transport of pharmaceuticals in aquatic ecosystems.
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Affiliation(s)
- Guoyang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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Sun W, Zhang C, Chen J, Zhang B, Zhang H, Zhang Y, Chen L. Accelerating biodegradation of a monoazo dye Acid Orange 7 by using its endogenous electron donors. JOURNAL OF HAZARDOUS MATERIALS 2017; 324:739-743. [PMID: 27887816 DOI: 10.1016/j.jhazmat.2016.11.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/12/2016] [Accepted: 11/18/2016] [Indexed: 06/06/2023]
Abstract
Biodegradation of a monoazo dye - Acid Orange 7 (AO7) was investigated by using an internal circulation baffled biofilm reactor. For accelerating AO7 biodegradation, endogenous electron donors produced from AO7 by UV photolysis were added into the reactor. The result shows that AO7 removal rate can be accelerated by using its endogenous electron donors, such as sulfanilic and aniline. When initial AO7 concentration was 13.6mg/L, electron donors generated by 8h UV photolysis were added into the same system. The biodegradation rate 0.4mg0.05h-1 was enhanced 60% than that without adding electron donor. Furthermore, sulfanilic and aniline were found to be the main endogenous electron carriers, which could accelerate the steps of the azo dye biodegradation.
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Affiliation(s)
- Weihua Sun
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China.
| | - Chengji Zhang
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China
| | - Jun Chen
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China
| | - Bingbing Zhang
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China
| | - Hongzhuan Zhang
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China
| | - Yongming Zhang
- Department of Environmental Science and Engineering, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, PR China.
| | - Lujun Chen
- School of Environment, Tsinghua University, Beijing 100084, PR China
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20
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Chen J, Zhang L, Huang T, Li W, Wang Y, Wang Z. Decolorization of azo dye by peroxymonosulfate activated by carbon nanotube: Radical versus non-radical mechanism. JOURNAL OF HAZARDOUS MATERIALS 2016; 320:571-580. [PMID: 27501877 DOI: 10.1016/j.jhazmat.2016.07.038] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/29/2016] [Accepted: 07/17/2016] [Indexed: 06/06/2023]
Abstract
Carbon nanotube (CNT) has been shown to effectively activate peroxymonosulfate (PMS) to remove contaminants, whereas controversial activation mechanisms (radical vs non-radical mechanism) were previously proposed. Here we report that radical-induced decolorization of acid orange 7 (AO7) dominated in the CNT activated PMS system, but non-radical mechanism was also involved at high Cl- concentration. CNT exhibited high activity in activating PMS to decolorize AO7. The decolorization rate of AO7 increased with increasing PMS dosages and CNT loadings, rising temperature and higher pH. Radical quenching and photoluminescence techniques confirmed the decolorization of AO7 in the CNT/PMS system was caused by the radical oxidation, which dominantly took place on the surface of CNT, rather than the bulk solution. The presence of Cl- exhibited a dual effect on AO7 decolorization. Low concentration of Cl- slightly inhibited AO7 decolorization, but further raising the concentration to above 0.1M significantly accelerated its decolorizaition. Cl- was confirmed to react with PMS to generate HClO, which effectively bleached AO7 through non-radical process rather than radical process. The decolorization of AO7 induced from the non-radical process exhibited different degradation products and less mineralization in comparison to that derived from radical process.
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Affiliation(s)
- Jiabin Chen
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215001, PR China
| | - Liming Zhang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215001, PR China
| | - Tianyin Huang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215001, PR China.
| | - Wenwei Li
- School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, PR China
| | - Ying Wang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215001, PR China
| | - Zhongming Wang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215001, PR China
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21
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Wu B, Yin R, Zhang G, Yu C, Zhang S. Effects of water chemistry on decolorization in three photochemical processes: Pro and cons of the UV/AA process. WATER RESEARCH 2016; 105:568-574. [PMID: 27693968 DOI: 10.1016/j.watres.2016.09.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/17/2016] [Accepted: 09/19/2016] [Indexed: 06/06/2023]
Abstract
The poor selectivity of hydroxyl radicals is a major restriction in the practical application of the UV/H2O2 process for dyeing wastewater treatment. As an alternative, the target-selective UV/acetylacetone (AA) process was found highly efficient for dye decolorization. For the proper selection and application of the two photochemical processes, the effects of water matrices, including common inorganic anions (Cl-, SO42-, NO3-, HCO3-), natural organic matter, metal cations (Mg2+, Mn2+, Cu2+, Fe3+, Cr3+), and temperature, on the photo-degradation of an azo dye, Acid Orange 7 (AO7), were systematically investigated. The experimental results demonstrate that the UV/AA process was more sensitive to inner filter effect. NO3-, Cu2+, and Fe3+ were all detrimental to the UV/AA process, whereas at certain concentrations they were beneficial to the UV/H2O2 process. However, even with severe inhibitory effects, the decolorization efficiency of the UV/AA process was still several times higher than that of the UV/H2O2 process. The results are helpful for us to better understand the mechanisms behind the UV/AA process and may shed light on the application of UV-based advanced oxidation processes for wastewater treatment.
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Affiliation(s)
- Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Guoyang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Chao Yu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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Wu B, Zhang G, Zhang S. Fate and implication of acetylacetone in photochemical processes for water treatment. WATER RESEARCH 2016; 101:233-240. [PMID: 27262551 DOI: 10.1016/j.watres.2016.05.083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 06/05/2023]
Abstract
Acetylacetone (AA), due to the peculiar enol-keto structures, has attracted wide scientific interests. In terms of photo-decolorization, it works much more efficiently than the well-known H2O2. However, there is very limited information on the photochemistry of AA in aqueous solutions. Herein, the photolysis kinetics, quantum yield, mass balance, decomposition pathway, and bioavailability of AA during UV irradiation were systematically investigated. It seems that photophysical processes predominated over photochemical ones when AA was irradiated with UV light. Although the quantum yield of AA (0.116) was much lower than that of H2O2 (1.0), the stronger light absorption of AA and the better overlap of the AA absorption spectrum with the solar emission spectrum, as well as the direct energy/electron transfer mechanisms, ensured its high efficiency in photochemical processes. The main degradation products of AA in photochemical processes were similar to the metabolic products in bio-fermentation. Besides, the irradiated AA solution showed a high bioavailability to the cells in activated sludge. Therefore, the UV/AA process might be a promising pre-treatment approach for bio-treatment. The results provide new insights into the photochemical fate and implication of β-diketones in aqueous solutions.
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Affiliation(s)
- Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Guoyang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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Detection of Organic Compounds in Water by an Optical Absorbance Method. SENSORS 2016; 16:s16010061. [PMID: 26742043 PMCID: PMC4732094 DOI: 10.3390/s16010061] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 12/30/2015] [Accepted: 12/30/2015] [Indexed: 11/17/2022]
Abstract
This paper proposes an optical method which allows determination of the organic compound concentration in water by measurement of the UV (ultraviolet) absorption at a wavelength of 250 nm~300 nm. The UV absorbance was analyzed by means of a multiple linear regression model for estimation of the total organic carbon contents in water, which showed a close correlation with the UV absorbance, demonstrating a high adjusted coefficient of determination, 0.997. The comparison of the TOC (total organic carbon) concentrations for real samples (tab water, sea, and river) calculated from the UV absorbance spectra, and those measured by a conventional TOC analyzer indicates that the higher the TOC value the better the agreement. This UV absorbance method can be easily configured for real-time monitoring water pollution, and built into a compact system applicable to industry areas.
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Wu B, Zhang S, Li X, Liu X, Pan B. Iron in non-hydroxyl radical mediated photochemical processes for dye degradation: Catalyst or inhibitor? CHEMOSPHERE 2015; 131:55-62. [PMID: 25765264 DOI: 10.1016/j.chemosphere.2015.02.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 01/27/2015] [Accepted: 02/14/2015] [Indexed: 06/04/2023]
Abstract
The acetylacetone (AA) mediated photochemical process has been proven as an efficient approach for decoloration. For azo dyes, the UV/AA process was several to more than ten times more efficient than the UV/H2O2 process. Iron is one of the most common elements on the earth. It is well known that iron can improve the UV/H2O2 process through thermal Fenton and photo-Fenton reactions. What will be the role of iron in the UV/AA process? Could iron-AA complexes act as photocatalysts in environmental remediation? To answer these questions, the photo-degradation of an azo dye, Acid Orange 7 (AO7), was conducted under the variant combinations of AA with iron species in both ionic (Fe2+, Fe3+) and complex (Fe(AA)3) forms. The pseudo-first-order decoloration rate constants of AO7 in these photochemical processes followed such an order: UV/Fe(II)/AA<UV/Fe(III)/AA<UV/Fe(AA)3<UV/AA. The results demonstrate that iron species, in either ionic or complex form, acts as an inhibitor rather than a catalyst in the UV/AA process. Based on spectroscopic analysis, the inner filter effect of iron and the competition between Fe(III) and AA for the complexation with AO7 were attributed to the inhibition effect of iron on the UV/AA process. The understanding of the role of iron provides insight into the practical application of the UV/AA process.
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Affiliation(s)
- Bingdang Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
| | - Xuchun Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Xitong Liu
- Department of Geography and Environmental Engineering, Johns Hopkins University, Baltimore, MD 21218-2686, United States
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
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25
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Cai C, Zhang H, Zhong X, Hou L. Ultrasound enhanced heterogeneous activation of peroxymonosulfate by a bimetallic Fe-Co/SBA-15 catalyst for the degradation of Orange II in water. JOURNAL OF HAZARDOUS MATERIALS 2014; 283:70-79. [PMID: 25262480 DOI: 10.1016/j.jhazmat.2014.08.053] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/17/2014] [Accepted: 08/10/2014] [Indexed: 06/03/2023]
Abstract
Mesoporous silica SBA-15 supported iron and cobalt (Fe-Co/SBA-15) was prepared and used as catalyst in the ultrasound (US) enhanced heterogeneous activation of peroxymonosulfate (PMS, HSO5(-)) process. The effects of some important reaction parameters on the removal of Orange II by US/Fe-Co/SBA-15/PMS process were investigated. The results indicated that the removal rate of Orange II was not significantly affected by the initial pH, and it increased with the higher PMS concentration, reaction temperature, Fe-Co/SBA-15 dosage and ultrasonic power. Furthermore, sulfate radicals (SO4(-)) were assumed to be the dominating reactive species for the Orange II decolorization. Moreover, the Fe-Co/SBA-15 catalyst showed high activity during the repeated experiments. The intermediate products were identified by GC-MS, thereby a plausible degradation pathway is proposed. In addition, the chemical oxygen demand (COD) removal efficiencies at 2 and 24h were 56.8% and 80.1%, respectively and the corresponding total organic carbon (TOC) removal efficiencies were 33.8 and 53.3%. Finally, toxicity tests with activated sludge showed that the toxicity of the solution increased during the first stage and then decreased significantly with the progress of the oxidation.
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Affiliation(s)
- Chun Cai
- Department of Environmental Engineering, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan 430079, China
| | - Hui Zhang
- Department of Environmental Engineering, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan 430079, China.
| | - Xing Zhong
- Department of Environmental Engineering, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan 430079, China
| | - Liwei Hou
- Department of Environmental Engineering, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory, Wuhan University, Wuhan 430079, China
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