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Wang Z, Lin X, Yang K, Lin D. Differential photodegradation processes of adsorbed polychlorinated biphenyls on biochar colloids with various pyrolysis temperatures. WATER RESEARCH 2024; 251:121174. [PMID: 38277821 DOI: 10.1016/j.watres.2024.121174] [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: 08/15/2023] [Revised: 12/31/2023] [Accepted: 01/19/2024] [Indexed: 01/28/2024]
Abstract
Despite the crucial role of photodegradation in the environmental transformation of organic pollutants, the photodegradation process of organic pollutants irreversibly absorbed on biochar colloids (BCCs) remains poorly understood. This study investigated the photodegradation processes and mechanisms of 2,4,4'-trichlorobiphenyl (PCB28) adsorbed on BCCs released from bulk biochars derived from bamboo chips at pyrolysis temperatures of 300, 500, and 700 °C. Results show that BCCs-adsorbed PCB28 could be degraded under simulated solar illumination (95-105 mW·cm-2) but at decreased photodegradation rates compared to the dissolved PCB28. The inhibition effect of BCCs on the PCB28 photodegradation increased with increasing pyrolysis temperature. After adsorptive binding to BCCs, the half-life of PCB28 (0.1 mg/L) was prolonged from 2.65 h for the dissolved PCB28 alone in deionized water to 7.48, 40.67, and 81.82 h in the presence of BCC300, BCC500, and BCC700 (5.0 mg/L), respectively. Mechanistically, the photodegradation of adsorbed pollutants was regulated by the photogenerated free radicals and surface functional groups of the low-temperature BCCs, as well as the defects and direct electron transfer capabilities of the high-temperature BCCs; PCB28 adsorbed on the low-temperature BCCs accepted electrons from persistent free radicals under light illumination, which led to PCB28 dechlorination, followed by ring-opening oxidation through hydroxyl radical attack, ultimately resulting in progressive mineralization; singlet oxygen caused preferential ring opening of adsorbed PCB28 on the high-temperature BCCs, preceding dechlorination. The photodegradation of BCCs-adsorbed PCB28 remained significant though more or less being inhibited under the effects of water pH, ionic strength, dissolved organic matters (humic acid and fulvic acid), and in natural water samples. These findings contribute to a better understanding of the structural properties of BCCs that impact phototransformation processes of adsorbed pollutants and facilitate an accurate assessment of the environmental risk associated with biochar application.
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Affiliation(s)
- Zhongmiao Wang
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Xintong Lin
- School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Kun Yang
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Ecological Civilization Academy, Anji 313300, China.
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Qin M, Wang YY, Xu M, Tang J, Tang X, Mahmood Q, Tang CJ. Characterization of the microplastic photoaging under the action of typical salt ions of biological nitrogen removal processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169596. [PMID: 38147940 DOI: 10.1016/j.scitotenv.2023.169596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/23/2023] [Accepted: 12/20/2023] [Indexed: 12/28/2023]
Abstract
Microplastics (MPs) are one of the most prevalent and diverse contaminants, and wastewater treatment plants are significant MP aggregators. Controlling the pollution caused by microplastics requires an understanding of how they age. The properties of the MPs photoaging process under the influence of salt ions typical of biological nitrogen elimination processes were disclosed in this work. The aging process of polyvinyl chloride microplastics (PVC-MPs) was greatly slowed down by greater HCO3- and NO2- concentrations, according to a comparison of the carbonyl index changes that occurred during photoaging. The carbonyl index had a negative correlation with the thermal stability of the photo-aged PVC-MPs, and aging accelerated the elimination of chlorine from the water. The samples were aged by UV radiation after 36 h at 40 °C, and the amount of chlorine eliminated was 10.13 times greater than that of the original MPs samples. It was discovered that the leachate concentration of aged MPs dramatically increased with decreasing particle size and was positively connected with the level of aging by comparing the concentration of leachate for two particle sizes (1 mm and 100 m). Photoaging caused MPs to become rougher, which in turn improved the NO3--N, NH4+-N, and NO2--N adsorption by PVC-MPs.
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Affiliation(s)
- Muchuan Qin
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China.
| | - Yun-Yan Wang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China.
| | - Mingfei Xu
- Dagang Oilfield Production Technology Research Institute, Binhai New Area, Tianjin 300280, China.
| | - Jia Tang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China
| | - Xi Tang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China.
| | - Qaisar Mahmood
- Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus, Pakistan.
| | - Chong-Jian Tang
- Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China.
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Kaleem M, Mumtaz AS, Hashmi MZ, Saeed A, Inam F, Waqar R, Jabeen A. Myco- and phyco-remediation of polychlorinated biphenyls in the environment: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:13994-14007. [PMID: 36550253 DOI: 10.1007/s11356-022-24902-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
Polychlorinated biphenyls (PCBs) are toxic organic compounds and pose serious threats to environment and public health. PCBs still exist in different environments such as air, water, soil, and sediments even on ban. This review summarizes the phyco- and myco-remediation technologies developed to detoxify the PCB-polluted sites. It was found that algae mostly use bioaccumulation to biodegradation strategies to reclaim the environment. As bio-accumulator, Ulva rigida C. Agardh has been best at 25 ng/g dry wt to remove PCBs. Evidently, Anabaena PD-1 is the only known PCB degrading alga and efficiently degrade Aroclor 1254 and dioxin-like PCBs up to 84.4% and 37.4% to 68.4%, respectively. The review suggested that factors such as choice of algal strains, response of microalgae, biomass, the rate of growth, and cost-effective cultivation conditions significantly influence the remediation of PCBs. Furthermore, the Anabaena sp. linA gene of Pseudomonas paucimobilis Holmes UT26 showed enhanced efficiency. Pleurotus ostreatus (Jacq.) P. Kumm is the most efficient PCB degrading fungus, degrading up to 98.4% and 99.6% of PCB in complex and mineral media, respectively. Combine metabolic activities of bacteria and yeast led to the higher detoxification of PCBs. Fungi-algae consortia would be a promising approach in remediation of PCBs. A critical analysis on potentials and limits of PCB treatment through fungal and algal biosystems have been reviewed, and thus, new insights have emerged for possible bioremediation, bioaccumulation, and biodegradation of PCBs.
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Affiliation(s)
- Muhammad Kaleem
- Department of Plant Sciences, Quaid-I-Azam University, Islamabad, Pakistan
| | - Abdul Samad Mumtaz
- Department of Plant Sciences, Quaid-I-Azam University, Islamabad, Pakistan
| | | | - Aamer Saeed
- Department of Chemistry, Quaid-I-Azam University, Islamabad, Pakistan
| | - Farooq Inam
- Department of Plant Sciences, Quaid-I-Azam University, Islamabad, Pakistan
| | - Rooma Waqar
- Department of Plant Sciences, Quaid-I-Azam University, Islamabad, Pakistan
| | - Amber Jabeen
- Department of Plant Sciences, Quaid-I-Azam University, Islamabad, Pakistan
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Ortiz Almirall X, Solà Yagüe N, Gonzalez-Olmos R, Díaz-Ferrero J. Photochemical degradation of persistent organic pollutants (PCDD/FS, PCBS, PBDES, DDTS and HCB) in hexane and fish oil. CHEMOSPHERE 2022; 301:134587. [PMID: 35427665 DOI: 10.1016/j.chemosphere.2022.134587] [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: 02/09/2022] [Revised: 03/31/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
This study has investigated the photochemical degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and some organochlorine pesticides, such as hexachlorobenzene (HCB) or dichloro-diphenyl-trichloroethane (DDT) in hexane under UV irradiation at 254 nm. All pollutants were completely degraded after 3.5 h of exposition to the UV light. Moreover, this technique was applied to remove persistent organic pollutants from fish oil, with eliminations of a 34% for PCDD/Fs, 53% for PCBs, 59% for HCB, 67% for PBDEs and 73% for DDTs after 12 h of exposition to the UV light (254 nm). Dioxin-like PCBs increased their concentration after the treatment, probably due to the dehalogenation of other more chlorinated congeners. The fatty acids analysis of the fish oil revealed that the most important ω-3 fatty acids -EPA and DHA-were degraded to 67 and 70% of their initial content respectively. For these reasons elimination of persistent organic pollutants with photochemical treatment has limited applications for oils with food-purposes. However, it still can be a useful technique for decontamination of industrial oils.
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Affiliation(s)
- X Ortiz Almirall
- Environmental Laboratory, Analytical and Applied Chemistry Department, IQS School of Engineering - Ramon Llull University, Via Augusta 390, 08017, Barcelona, Spain.
| | - N Solà Yagüe
- Environmental Laboratory, Analytical and Applied Chemistry Department, IQS School of Engineering - Ramon Llull University, Via Augusta 390, 08017, Barcelona, Spain
| | - R Gonzalez-Olmos
- Chemical Engineering and Material Sciences Department, IQS School of Engineering - Ramon Llull University, Via Augusta 390, 08017, Barcelona, Spain
| | - J Díaz-Ferrero
- Environmental Laboratory, Analytical and Applied Chemistry Department, IQS School of Engineering - Ramon Llull University, Via Augusta 390, 08017, Barcelona, Spain
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Huang C, Zeng Y, Luo X, Ren Z, Tian Y, Mai B. Comprehensive exploration of the ultraviolet degradation of polychlorinated biphenyls in different media. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 755:142590. [PMID: 33059143 DOI: 10.1016/j.scitotenv.2020.142590] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
As one of the most important natural transformation processes, photodegradation deserves more attention and research. In the current work, we comprehensively explored the photochemical behaviors of polychlorinated biphenyls (PCBs) in n-hexane (Hex), methanol/water, and silica gel under UV-irradiation. Photodegradation rates were found to be faster in methanol/water than in Hex. All of the three photochemical systems generated sigmatropic rearrangement products. The dominant photodegradation pathways were dechlorination, dechlorination/methoxylation/hydroxylation, and hydroxylation in Hex, methanol/water, and silica gel systems, respectively. Furthermore, some new photodegradation products, such as polychlorinated biphenyl ethers, polychlorinated dibenzofurans, polychlorinated biphenylenes, and methylated polychlorinated biphenyls, are reported for the first time. These findings would provide deeper insight into the phototransformation behaviors of PCBs.
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Affiliation(s)
- Chenchen Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zihe Ren
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yankuan Tian
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Chen Y, Zhu N, Luo Y, Hu K, Liu Y. Featured structure-activity relationships for some tri- and tetrachlorobiphenyls in human CYP2E1-activated mutagenicity - Impact of the extent of ortho-chlorination. CHEMOSPHERE 2018; 210:467-475. [PMID: 30025364 DOI: 10.1016/j.chemosphere.2018.06.169] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/05/2018] [Accepted: 06/27/2018] [Indexed: 06/08/2023]
Abstract
Polychlorinated biphenyls (PCBs) as a group of persistent organic pollutants are confirmed human carcinogens; however, their mutagenicity remains mostly unknown. We have reported the mutagenicity of some PCBs with one to four chlorines in mammalian cells expressing human CYP2E1. To further explore the structural requirements for the mutagenicity of PCBs, eight tri- and tetrachlorobiphenyls untested before were investigated for the induction of gene mutations and micronuclei in a V79-derived cell line expressing both human CYP2E1 and sulfotransferase (SULT) 1A1 (V79-hCYP2E1-hSULT1A1), with SULT1A1 activity inhibited by pentachlorophenol, a potent SULT1 inhibitor. 2,2',6-Tri-, 2,3',6-tri, 2,4',6-tri-, and 2,2',5-trichlorobiphenyls (PCBs 19, 27, 32, and 18, respectively) induced micronuclei and gene mutations in V79-hCYP2E1-hSULT1A1 cells, at potencies slightly higher than 2,6-dichlorobiphenyl, but one order of magnitude below that by 2,3,3'- and 2,3,4'-trichlorobiphenyls as reported recently; in the parental V79-Mz cells, they were nonmutagenic and weak in micronuclei induction. Among the four tetrachlorobiphenyls with varying number of ortho chlorines, 2,3,3',4'-tetrachlorobiphenyl (PCB 56) induced both micronuclei and gene mutations in V79-hCYP2E1-hSULT1A1 cells with a potency greater than the above compounds; however, 2,2',3,3'-tetrachlorobiphenyl was equivocal and 2,2',3,6'-tetra- and 2,2',6,6'-tetrachlorobiphenyls inactive in V79-hCYP2E1-hSULT1A1 cells. Immunofluorescent staining of micronuclei formed by PCBs 32 and 56 in V79-hCYP2E1-hSULT1A1 cells with centromere protein B antibodies indicated that they were predominantly whole chromosomes, implying aneugenic potentials. This study suggests that tri- and tetrachlorobiphenyls with a single ortho chlorine can be most mutagenic under activation by human CYP2E1, and greater numbers of ortho chlorines may cause a drastic decline in the activity, especially for tetrachlorobiphenyls.
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Affiliation(s)
- Yuting Chen
- Department of Toxicology, School of Public Health, Southern Medical University, 1023 S. Shatai Road, Guangzhou 510515, China
| | - Na Zhu
- Department of Toxicology, School of Public Health, Southern Medical University, 1023 S. Shatai Road, Guangzhou 510515, China
| | - Yuyi Luo
- Department of Toxicology, School of Public Health, Southern Medical University, 1023 S. Shatai Road, Guangzhou 510515, China
| | - Keqi Hu
- Department of Toxicology, School of Public Health, Southern Medical University, 1023 S. Shatai Road, Guangzhou 510515, China
| | - Yungang Liu
- Department of Toxicology, School of Public Health, Southern Medical University, 1023 S. Shatai Road, Guangzhou 510515, China.
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Wang S, Wang Z. Elucidating Direct Photolysis Mechanisms of Different Dissociation Species of Norfloxacin in Water and Mg 2+ Effects by Quantum Chemical Calculations. Molecules 2017; 22:molecules22111949. [PMID: 29137112 PMCID: PMC6150356 DOI: 10.3390/molecules22111949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 11/03/2017] [Accepted: 11/08/2017] [Indexed: 11/29/2022] Open
Abstract
The study of pollution due to combined antibiotics and metals is urgently needed. Photochemical processes are an important transformation pathway for antibiotics in the environment. The mechanisms underlying the effects of metal-ion complexation on the aquatic photochemical transformation of antibiotics in different dissociation forms are crucial problems in science, and beg solutions. Herein, we investigated the mechanisms of direct photolysis of norfloxacin (NOR) in different dissociation forms in water and metal ion Mg2+ effects using quantum chemical calculations. Results show that different dissociation forms of NOR had different maximum electronic absorbance wavelengths (NOR2+ < NOR0 < NOR+) and showed different photolysis reactivity. Analysis of transition states (TS) and reaction activation energies (Ea) indicated NOR+ generally underwent loss of the piperazine ring (C10–N13 bond cleavage) and damage to piperazine ring (N13–C14 bond cleavage). For NOR2+, the main direct photolysis pathways were de-ethylation (N7–C8 bond cleavage) and decarboxylation (C2–C5 bond cleavage). Furthermore, the presence of Mg2+ changed the order of the wavelength at maximum electronic absorbance (NOR+-Mg2+ < NOR0-Mg2+ < NOR2+-Mg2+) and increased the intensities of absorbance peaks of all three dissociation species of NOR, implying that Mg2+ played an important role in the direct photolysis of NOR0, NOR+, and NOR2+. The calculated TS results indicated that the presence of Mg2+ increased Ea for most direct photolysis pathways of NOR, while it decreased Ea for some direct photolysis pathways such as the loss of the piperazine ring and the damage of the piperazine ring of NOR0 and the defluorination of NOR+.
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Affiliation(s)
- Se Wang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Zhuang Wang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.
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Shi J, Bi W, Li S, Dong W, Chen J. Reaction Mechanism of 4-Chlorobiphenyl and the NO 3 Radical: An Experimental and Theoretical Study. J Phys Chem A 2017; 121:3461-3468. [PMID: 28402663 DOI: 10.1021/acs.jpca.6b08626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Experiment and theoretical chemistry calculations were conducted to elucidate the mechanism of the reaction between 4-chlorobiphenyl (4-CB) and the NO3 radical. The degradation of PCBs was investigated mechanistically through transient absorption spectroscopy technology and high-accuracy theoretical calculation by using 4-CB as the model. Laser flash photolysis (LFP) experiments were performed at 355 nm. The main intermediate was analyzed through transient absorption spectroscopy and identified to be a charge transfer complex (CTC). The final products were identified through GC-MS analysis. The ground states and excited states of the reactants were calculated through density functional theory (DFT) method. The absorption bands at 400 and 700 nm show good agreement with the experimental results. The ratio of absorbance at 400 and 700 nm is 1.6, and the experimental value is 1.8. Analysis of the charge population indicated that one unit charge transfer from 4-CB to NO3. The entire reaction process was divided into two phases. In the first phase, the CTC intermediate was formed by electrostatic attraction between 4-CB and the NO3 radical. In the second phase, the most important channel of subsequent reactions is the σ-complex as an intermediate formed by N-C coupling. The final product 4-chloro,2-nitrobiphenyl was generated with the breakage of BC-H and BN-O, and benzene derivatives were formed by other channels.
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Affiliation(s)
- Jin Shi
- Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, P. R. China
| | - Wenlong Bi
- Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, P. R. China
| | - Shenmin Li
- College of Environmental and Chemical Engineering, Dalian University , Dalian 116622, P. R. China
| | - Wenbo Dong
- Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, P. R. China
| | - Jianmin Chen
- Department of Environmental Science and Engineering, Fudan University , Shanghai 200433, P. R. China
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Qu R, Liu J, Li C, Wang L, Wang Z, Wu J. Experimental and theoretical insights into the photochemical decomposition of environmentally persistent perfluorocarboxylic acids. WATER RESEARCH 2016; 104:34-43. [PMID: 27508972 DOI: 10.1016/j.watres.2016.07.071] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/18/2016] [Accepted: 07/29/2016] [Indexed: 06/06/2023]
Abstract
Decomposition of perfluorocarboxylic acids (PFCAs) is of great significance due to their global distribution, persistence and toxicity to organisms. In this study, the photodegradation of a series of PFCAs (∼C2C12) in water by a medium-pressure mercury lamp was experimentally and theoretically examined. We found that photolysis of PFCAs all follow pseudo-first-order kinetics with the rate constant (kapp) increasing with carbon chain lengths, except for trifluoroacetic acid (TFA) which cannot be degraded by the polychromatic irradiation. Product analysis showed that the PFCAs were mainly decomposed into shorter carbon chain length PFCAs in a stepwise manner, with the accumulation of TFA and fluoride ions as the end products. Moreover, a small amount of perfluoroolefins (CnF2n) was determined as gas-phase products. Wiberg bond order calculations confirmed the cleavage of the CC bond between carboxylic carbon and the adjacent carbon as the first reaction step, and density functional theory-based calculations revealed that kapp value is correlated with some molecular structural parameters. In the case of mixture irradiation, the evolution profiles of individual PFCAs were different from that in single-component systems, due to the dynamic balance between production and degradation. This work reveals the main molecular descriptors controlling the degradation rate of different PFCAs species, and improves the general understanding on the photodegradation mechanisms, which will provide useful information for future researches.
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Affiliation(s)
- Ruijuan Qu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu, Nanjing 210023, PR China
| | - Jiaoqin Liu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu, Nanjing 210023, PR China
| | - Chenguang Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu, Nanjing 210023, PR China
| | - Liansheng Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu, Nanjing 210023, PR China
| | - Zunyao Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu, Nanjing 210023, PR China.
| | - Jichun Wu
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Hydrosciences Department, Nanjing University, Nanjing 210023, PR China.
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Zeng X, Qu R, Feng M, Chen J, Wang L, Wang Z. Photodegradation of Polyfluorinated Dibenzo-p-Dioxins in Organic Solvents: Experimental and Theoretical Studies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:8128-8134. [PMID: 27380414 DOI: 10.1021/acs.est.6b02682] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Eighteen polyfluorinated dibenzo-p-dioxins (PFDDs) were synthesized by pyrolysis of fluorophenols. Using a 500 W Xe lamp as the light source, the PFDDs photodegradation kinetics in n-hexane were investigated. The photolysis reactions obeyed the pseudo-first-order rate equation, and higher fluorinated PFDDs tended to photolyze more slowly. Theoretically calculated parameters reflecting the molecular structural properties were used to develop a new model of PFDDs photolysis rates. The results indicated that the substitution pattern for fluorine atoms and the C-O bond length were major factors in the photolysis of PFDDs. We selected octafluorinated dibenzo-p-dioxin (OFDD) as a representative PFDDs to explore the influence of solvent on the photolysis rate of PFDDs, and the results indicated that neither the polarity nor donor hydrogen of organic solvents are independent influencing factors. Mechanistic pathways for the photolysis of OFDD in n-hexane were first studied. The results indicated that photodegradation of OFDD produces octafluorinated dihydroxybiphenyls, octafluorinated phenoxyphenols, and fluorinated phenols. The major pathway for photodegradation of OFDD was C-O bond cleavage. Defluorination reactions did not occur during the photolysis process.
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Affiliation(s)
- Xiaolan Zeng
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
- College of Chemistry and Chemical Engineering, Xinyang Normal University , Henan Xinyang 464000, PR China
| | - Ruijuan Qu
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
| | - Mingbao Feng
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
| | - Jing Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
| | - Liansheng Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
| | - Zunyao Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environment, Nanjing University , Jiangsu Nanjing 210023, PR China
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Zhu X, Wang Y, Qin W, Zhang S, Zhou D. Distribution of free radicals and intermediates during the photodegradation of polychlorinated biphenyls strongly affected by cosolvents and TiO₂ catalyst. CHEMOSPHERE 2016; 144:628-634. [PMID: 26401639 DOI: 10.1016/j.chemosphere.2015.09.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 07/20/2015] [Accepted: 09/08/2015] [Indexed: 06/05/2023]
Abstract
Polychlorinated biphenyls (PCBs) pose potential ecological risk because of their high toxicity and carcinogenicity. Photodegradation, which is an important process for the removal of PCBs, is greatly influenced by the cosolvent and catalyst. Hence, it is important to explore their effects on the photodegradation behavior of PCBs. In this study, 2,4,4'-trichlorobiphenyl (PCB28) was selected as a model compound, and the effects of two typical cosolvents, namely acetone and ethanol, and TiO2 catalyst on the distributions of free radicals and intermediates were investigated. Interestingly, the TiO2 catalyst did not promote PCB28 photodegradation. Moreover, the free radical distribution was greatly influenced in the presence of the TiO2 catalyst, while was only slightly affected in its absence by the cosolvent kinds. The main photodegradation pathways are proposed on the basis of the distribution of detected intermediates, which were significantly regulated by both the cosolvent and TiO2 catalyst. The results provide novel insights into the photodegradation of PCBs and may have important implications for choosing cosolvent in desorbing soil PCBs and consequently enhancing PCBs degradation.
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Affiliation(s)
- Xiangdong Zhu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Yujun Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Wenxiu Qin
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Dongmei Zhou
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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12
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Shah S, Zhang H, Song X, Hao C. Quantum chemical study of the photolysis mechanisms of sulfachloropyridazine and the influence of selected divalent metal ions. CHEMOSPHERE 2015; 138:765-769. [PMID: 26291757 DOI: 10.1016/j.chemosphere.2015.07.068] [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: 01/08/2015] [Revised: 07/15/2015] [Accepted: 07/29/2015] [Indexed: 06/04/2023]
Abstract
Sulfonamides have been found in aquatic environments. Degradation of sulfachloropyridazine (SCP) mainly proceeds through direct and indirect photolysis in the aquatic environment. However, the mechanisms underlying the triplet photolysis of SCP and the influence of metal ions on the photolysis mechanism have not yet been fully explained. In this study, we elucidated the triplet photolysis mechanisms of SCP and the effects of three selected metal ions (Zn(2+), Ca(2+), and Cu(2+)) on the SCP photolysis mechanisms using quantum chemical calculation. Optimization of molecular structures and reaction pathways analysis of SCP were carried out at the B3LYP/6-31+G(d,p) level of theory. Two minimum energy pathways were investigated in the triplet photolysis of SCP. In Step 2 of Path-I, the photolysis product of SCP is a sulfur dioxide extrusion product, (4-(3-chloro-6-iminopyridazine-1(6H)-yl)aniline). The estimated activation energies of Step 2 and Step 3 of Path-I were much higher than in Path-II. Therefore, Path-II was found as the lowest energy pathway to obtain the SCP photoproducts, and Step 2 of Path-II was confirmed as the rate-determining step (RDS) in the photolysis mechanism of SCP. For the RDS of Path-II, computations with the three metal ions complexes (IM1-Cu(2+), IM1-Ca(2+), and IM1-Zn(2+)) show that the metal ions Cu(2+) and Ca(2+) promote triplet-sensitized photolysis of SCP by reducing the activation energy of RDS of Path-II, whereas Zn(2+) showed an inhibitory effect in photolysis of SCP by increasing the activation energy.
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Affiliation(s)
- Shaheen Shah
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Heming Zhang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Xuedan Song
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Ce Hao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.
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13
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Zhang H, Jiang X, Lu L, Xiao W. Biodegradation of polychlorinated biphenyls (PCBs) by the novel identified cyanobacterium Anabaena PD-1. PLoS One 2015; 10:e0131450. [PMID: 26177203 PMCID: PMC4503305 DOI: 10.1371/journal.pone.0131450] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Accepted: 06/02/2015] [Indexed: 11/24/2022] Open
Abstract
Polychlorinated biphenyls (PCBs), a class of hazardous pollutants, are difficult to dissipate in the natural environment. In this study, a cyanobacterial strain Anabaena PD-1 showed good resistance against PCB congeners. Compared to a control group, chlorophyll a content decreased 3.7% and 11.7% when Anabaena PD-1 was exposed to 2 and 5 mg/L PCBs for 7 d. This cyanobacterial strain was capable of decomposing PCB congeners which was conclusively proved by determination of chloride ion concentrations in chlorine-free medium. After 7 d, the chloride ion concentrations in PCB-treated groups (1, 2, 5 mg/L) were 3.55, 3.05, and 2.25 mg/L, respectively. The genetic information of strain PD-1 was obtained through 16S rRNA sequencing analysis. The GenBank accession number of 16S rRNA of Anabaena PD-1 was KF201693.1. Phylogenetic tree analysis clearly indicated that Anabaena PD-1 belonged to the genus Anabaena. The degradation half-life of Aroclor 1254 by Anabaena PD-1 was 11.36 d; the total degradation rate for Aroclor 1254 was 84.4% after 25 d. Less chlorinated PCB congeners were more likely to be degraded by Anabaena PD-1 in comparison with highly chlorinated congeners. Meta- and para-chlorines in trichlorodiphenyls and tetrachlorobiphenyls were more susceptible to dechlorination than ortho-chlorines during the PCB-degradation process by Anabaena PD-1. Furthermore, Anabaena PD-1 can decompose dioxin-like PCBs. The percent biodegradation of 12 dioxin-like PCBs by strain PD-1 ranged from 37.4% to 68.4% after 25 days. Results above demonstrate that Anabaena PD-1 is a PCB-degrader with great potential for the in situ bioremediation of PCB-contaminated paddy soils.
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Affiliation(s)
- Hangjun Zhang
- College of Life and Environmental Sciences, Hangzhou Normal University, Xuelin Road 16#, Xiasha Gaojiao Dongqu, Hangzhou 310036, Zhejiang Province, China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou 310036, China
- * E-mail:
| | - Xiaojun Jiang
- College of Life and Environmental Sciences, Hangzhou Normal University, Xuelin Road 16#, Xiasha Gaojiao Dongqu, Hangzhou 310036, Zhejiang Province, China
| | - Liping Lu
- College of Life and Environmental Sciences, Hangzhou Normal University, Xuelin Road 16#, Xiasha Gaojiao Dongqu, Hangzhou 310036, Zhejiang Province, China
| | - Wenfeng Xiao
- College of Life and Environmental Sciences, Hangzhou Normal University, Xuelin Road 16#, Xiasha Gaojiao Dongqu, Hangzhou 310036, Zhejiang Province, China
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14
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Luo J, Hu J, Wei X, Fu L, Li L. Dehalogenation of persistent halogenated organic compounds: A review of computational studies and quantitative structure-property relationships. CHEMOSPHERE 2015; 131:17-33. [PMID: 25765260 DOI: 10.1016/j.chemosphere.2015.02.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 12/20/2014] [Accepted: 02/03/2015] [Indexed: 06/04/2023]
Abstract
Dehalogenation is one of the highly important degradation reactions for halogenated organic compounds (HOCs) in the environment, which is also being developed as a potential type of the remediation technologies. In combination with the experimental results, intensive efforts have recently been devoted to the development of efficient theoretical methodologies (e.g. multi-scale simulation) to investigate the mechanisms for dehalogenation of HOCs. This review summarizes the structural characteristics of neutral molecules, anionic species and excited states of HOCs as well as their adsorption behavior on the surface of graphene and the Fe cluster. It discusses the key physiochemical properties (e.g. frontier orbital energies and thermodynamic properties) calculated at various levels of theory (e.g. semiempirical, ab initio, density functional theory (DFT) and the periodic DFT) as well as their connections to the reactivity and reaction pathway for the dehalogenation. This paper also reviews the advances in the linear and nonlinear quantitative structure-property relationship models for the dehalogenation kinetics of HOCs and in the mathematical modeling of the dehalogenation processes. Furthermore, prospects of further expansion and exploration of the current research fields are described in this article.
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Affiliation(s)
- Jin Luo
- Guizhou Provincial Key Laboratory for Information Systems of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, PR China
| | - Jiwei Hu
- Guizhou Provincial Key Laboratory for Information Systems of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, PR China.
| | - Xionghui Wei
- Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China
| | - Liya Fu
- Guizhou Provincial Key Laboratory for Information Systems of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, PR China
| | - Lingyun Li
- Guizhou Provincial Key Laboratory for Information Systems of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, PR China
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15
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Wang S, Song X, Hao C, Gao Z, Chen J, Qiu J. Elucidating triplet-sensitized photolysis mechanisms of sulfadiazine and metal ions effects by quantum chemical calculations. CHEMOSPHERE 2015; 122:62-69. [PMID: 25496743 DOI: 10.1016/j.chemosphere.2014.11.007] [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: 05/22/2014] [Accepted: 11/02/2014] [Indexed: 06/04/2023]
Abstract
Sulfadiazine (SDZ) mainly proceeds triplet-sensitized photolysis with dissolved organic matter (DOM) in the aquatic environment. However, the mechanisms underlying the triplet-sensitized photolysis of SDZ with DOM have not been fully worked out. In this study, we investigated the mechanisms of triplet-sensitized photolysis of SDZ(0) (neutral form) and SDZ(-) (anionic form) with four DOM analogues, i.e., fluorenone (FL), thioxanthone (TX), 2-acetonaphthone (2-AN), and 4-benzoylbenzoic acid (CBBP), and three metal ions (i.e., Mg(2+), Ca(2+), and Zn(2+)) effects using quantum chemical calculations. Results indicated that the triplet-sensitized photolysis mechanism of SDZ(0) with FL, TX, and 2-AN was hydrogen transfer, and with CBBP was electron transfer along with proton transfer (for complex SDZ(0)-CBBP2) and hydrogen transfer (for complex SDZ(0)-CBBP1). The triplet-sensitized photolysis mechanisms of SDZ(-) with FL, TX, and CBBP was electron transfer along with proton transfer, and with 2-AN was hydrogen transfer. The triplet-sensitized photolysis product of both SDZ(0) and SDZ(-) was a sulfur dioxide extrusion product (4-(2-iminopyrimidine-1(2H)-yl)aniline), but the formation routs of the products for SDZ(0) and SDZ(-) were different. In addition, effects of the metal ions on the triplet-sensitized photolysis of SDZ(0) and SDZ(-) were different. The metal ions promoted the triplet-sensitized photolysis of SDZ(0), but inhibited the triplet-sensitized photolysis of SDZ(-).
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Affiliation(s)
- Se Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Xuedan Song
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Ce Hao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.
| | - Zhanxian Gao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jieshan Qiu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
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16
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Luo J, Hu J, Wei X, Li L, Huang X. Excited States and photodebromination of selected polybrominated diphenyl ethers: computational and quantitative structure--property relationship studies. Int J Mol Sci 2015; 16:1160-78. [PMID: 25569092 PMCID: PMC4307296 DOI: 10.3390/ijms16011160] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 12/24/2014] [Indexed: 12/16/2022] Open
Abstract
This paper presents a density functional theory (DFT)/time-dependent DFT (TD-DFT) study on the lowest lying singlet and triplet excited states of 20 selected polybrominateddiphenyl ether (PBDE) congeners, with the solvation effect included in the calculations using the polarized continuum model (PCM). The results obtained showed that for most of the brominated diphenyl ether (BDE) congeners, the lowest singlet excited state was initiated by the electron transfer from HOMO to LUMO, involving a π–σ* excitation. In triplet excited states, structure of the BDE congeners differed notably from that of the BDE ground states with one of the specific C–Br bonds bending off the aromatic plane. In addition, the partial least squares regression (PLSR), principal component analysis-multiple linear regression analysis (PCA-MLR), and back propagation artificial neural network (BP-ANN) approaches were employed for a quantitative structure-property relationship (QSPR) study. Based on the previously reported kinetic data for the debromination by ultraviolet (UV) and sunlight, obtained QSPR models exhibited a reasonable evaluation of the photodebromination reactivity even when the BDE congeners had same degree of bromination, albeit different patterns of bromination.
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Affiliation(s)
- Jin Luo
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Jiwei Hu
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Xionghui Wei
- Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
| | - Lingyun Li
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Xianfei Huang
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
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17
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Wang S, Hao C, Gao Z, Chen J, Qiu J. Theoretical investigations on direct photolysis mechanisms of polychlorinated diphenyl ethers. CHEMOSPHERE 2014; 111:7-12. [PMID: 24997893 DOI: 10.1016/j.chemosphere.2014.03.040] [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: 10/03/2013] [Revised: 02/20/2014] [Accepted: 03/07/2014] [Indexed: 06/03/2023]
Abstract
Polychlorinated diphenyl ethers (PCDEs) are a focus of current environmental concern as a group of ubiquitous potential persistent organic pollutants. There are still significant gaps in our knowledge concerning the photolysis mechanisms of PCDEs. In this study, the direct photolysis mechanisms of PCDEs were investigated by density functional theory. The direct photolysis of PCDEs has three potential reaction pathways including photodechlorination, C-O bond photodissociation, and PCDFs formation. Taking a representative PCDE (i.e., CDE8) for example, we found that C-Cl bond dissociation is the rate-determining step for the photodechlorination. Chlorobenzene is predicted to be photoproduct of CDE8 through the photodissociation of the C-O bond. Furthermore, the calculated mean bond dissociation energies of both C-Cl and C-O bonds of 20 PCDEs decrease with the increased degree of chlorination. It is also found that the photoactivity of PCDEs increases with an increase of chlorination degree by evaluating the average charge of Cl atoms and mean bond dissociation energies of C-Cl and C-O bonds from reaction thermodynamics. Our findings provided a new insight into the mechanisms of direct photolysis of PCDEs, which may be useful in the future in utilizing quantum chemistry calculation in investigating the behavior and fate of organic pollutants in the environment.
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Affiliation(s)
- Se Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Ce Hao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.
| | - Zhanxian Gao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jieshan Qiu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
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18
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Elucidating photodehalogenation mechanisms of polychlorinated and polybrominated dibenzo-p-dioxins and dibenzofurans and Mg2+ effects by quantum chemical calculations. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2014.03.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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