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Fouladi-Fard R, Yousefi N, Golmohammadi AM, Salehiparvar K, Khazaei M, Mahvi AH. Transformers polychlorinated biphenyls analysis and waste management in gas companies, case study: Iran. INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 2021. [DOI: 10.1080/03067319.2021.1887857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Affiliation(s)
- Reza Fouladi-Fard
- Research Center for Environmental Pollutants, Qom University of Medical Sciences, Qom, Iran
- School of Health, Qom University of Medical Sciences, Qom, Iran
| | - Nader Yousefi
- School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | | | - Mohammad Khazaei
- Research Center for Health Sciences and Department of Environmental Health Engineering, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Amir Hossein Mahvi
- School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
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Khammar S, Bahramifar N, Younesi H. Preparation and surface engineering of CM-β-CD functionalized Fe 3O 4@TiO 2 nanoparticles for photocatalytic degradation of polychlorinated biphenyls (PCBs) from transformer oil. JOURNAL OF HAZARDOUS MATERIALS 2020; 394:122422. [PMID: 32200245 DOI: 10.1016/j.jhazmat.2020.122422] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 06/10/2023]
Abstract
The aim of the present research is to investigate the efficiency of surface-modified magnetic nanoparticles for photocatalytic degradation of PCBs from transformer oil. Therefore, CMCD-Fe3O4@TiO2 was successfully produced via grafting of carboxymethyl-β-cyclodextrin (CM-β-CD) onto the core-shell titania magnetic nanoparticles surface. The photocatalytic efficiency of CMCD-Fe3O4@TiO2 for degradation of PCBs was systematically evaluated using an experimental design and the process parameters were optimized by response surface methodology (RSM). The central composite design (CCD) with four experimental parameters was used successfully in the modeling and optimization of photocatalytic efficiency in removing PCBs from transformer oil. ANOVA analysis confirmed a high R-squared value of 0.9769 describing the goodness of fit of the proposed model for the significance estimation of the individual and the interaction effects of variables. The optimal degradation yields of PCBs was achieved 83 % at a temperature of 25 °C, time of 16 min, the dosage of the catalyst of 8.35 mg and oil: ethanol ratio of 1:5. These findings encourage the practical use of CM-β-CD-Fe3O4@TiO2 as a promising and alternative photocatalyst on an industrial scale for the cleaning of organic pollutants such as PCBs due to its environmental friendliness, the benefit of magnetic separation and good reusability after five times.
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Affiliation(s)
- Sanaz Khammar
- Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356 Nour, Mazandaran, Iran
| | - Nader Bahramifar
- Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356 Nour, Mazandaran, Iran.
| | - Habibollah Younesi
- Department of Environmental Sciences, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, P.O. Box 46414-356 Nour, Mazandaran, Iran
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Photolysis of polychlorobiphenyls in the presence of nanocrystalline TiO2 and CdS/TiO2. REACTION KINETICS MECHANISMS AND CATALYSIS 2019. [DOI: 10.1007/s11144-019-01543-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ryoo KS, Choi JH, Hong YP. Treatment of PCB-Laden Transformer Oil with Polyethylene Glycols and Alkaline Hydroxide. B KOREAN CHEM SOC 2015. [DOI: 10.1002/bkcs.10199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Keon Sang Ryoo
- Department of Applied Chemistry; Andong National University; Andong 760-749 Korea
| | - Jong-Ha Choi
- Department of Applied Chemistry; Andong National University; Andong 760-749 Korea
| | - Yong Pyo Hong
- Department of Applied Chemistry; Andong National University; Andong 760-749 Korea
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Qi Z, Buekens A, Liu J, Chen T, Lu S, Li X, Cen K. Some technical issues in managing PCBs. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:6448-6462. [PMID: 23812787 DOI: 10.1007/s11356-013-1926-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/10/2013] [Indexed: 06/02/2023]
Abstract
Polychlorinated biphenyls (PCBs) were important industrial chemicals featuring high thermal and chemical stability and low flammability. They were widely used as dielectric and thermal fluid in closed electro-technical applications (transformers, capacitors…) and also in numerous dispersive uses, ranking from auto-copying paper to sealant or coatings. During the 1960s, severe environmental consequences started becoming apparent. The stability of PCBs contributed to their persistence in the environment, their lipophilic character to bio-magnification. Fish-eating species seemed threatened in their existence. In Japan and in Taiwan, thousands of people consumed PCB-contaminated oil. The production of PCBs stopped completely during the 1980s. Usage could continue in closed applications only. In this paper, particular attention is given to two issues: the cleaning of PCB electric transformers and the potential impact of PCB-containing building materials. Other contributions will cover the management and treatment of PCB-contaminated soil, sludge or fly ash. The complete survey is being prepared by request of the Knowledge Center for Engineers and Professionals.
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Affiliation(s)
- Zhifu Qi
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, 310027, China
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Kong J, Achari G, Langford CH. Dechlorination of polychlorinated biphenyls in transformer oil using UV and visible light. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2013; 48:92-98. [PMID: 23030392 DOI: 10.1080/10934529.2012.707856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A study on dechlorination of PCB138 in transformer oil (TO) and 2-propanol (IPA) using 254 nm ultraviolet (UV) light as well as dye sensitized visible light has been conducted. Studies on dechlorination of polychlorinated biphenyls (PCBs) in TO using visible light in the presence of methylene blue (MB) and triethylamine (TEA) (providing a 'photocatalytic' cycle) in both deaerated and aerated conditions have been conducted to determine effects of TO, MB and TEA on reaction rates. The results show that photolytic methods are effective in treating PCBs in TO, and that the oil plays a limited adverse role. Under UV irradiation, PCB 138 can be >99% dechlorinated in the presence 0.06% (w/w) TO in IPA within 1 h with a rate constant of 0.0853 min(-1), while 47% of PCB138 can be dechlorinated in 92.1% (w/w) TO in IPA within 2 h with a rate constant of 0.0051 min(-1). In the 'photocatalytic' system, 94% reduction of PCB 138 was achieved within 30 min with a rate constant of 0.0968 min(-1) when the solvent was 60.70% (w/w) TO in IPA, while 71% dechlorination of PCB138 was achieved within 30 min with a rate constant of 0.0382 min(-1) when 81.62% (w/w) TO was present. In treatment of 30-73 ppm PCBs in TO, the optimal concentration of MB and TEA were found to be 0.5 g/L and 58.08 g/L respectively. Because of quenching by oxygen, deaeration of the solution is necessary for an efficient reaction. The photocatalytic system is especially adapted for treating lower concentration of PCBs in TO.
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Affiliation(s)
- Jiansong Kong
- Department of Civil Engineering, University of Calgary, Calgary, Canada
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Ryoo KS, Hong YP, Ahn CJ. A Comparative Study on Adsorption Characteristics of PCBs in Transformer Oil Using Various Adsorbents. JOURNAL OF THE KOREAN CHEMICAL SOCIETY-DAEHAN HWAHAK HOE JEE 2012. [DOI: 10.5012/jkcs.2012.56.6.692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Yu DN, Macawile MCA, Abella LC, Gallardo SM. Degradation of polychlorinated biphenyls in aqueous solutions after UV-peroxide treatment: focus on toxicity of effluent to primary producers. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2011; 74:1607-1614. [PMID: 21531462 DOI: 10.1016/j.ecoenv.2011.04.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 04/05/2011] [Accepted: 04/15/2011] [Indexed: 05/30/2023]
Abstract
The combination of UV irradiation and hydrogen peroxide (UV-H(2)O(2)) was shown to be effective in treating water spiked with 2,2',4,4',5,5'-hexachlorobipheny (PCB 153), reducing its concentration by as much as 98%. To test the toxicity of the effluent, bioassays involving three species of primary producers were performed. Results showed the effluent exerting an adverse effect on the algae Scenedesmus bijugatus and the duckweed Lemna paucicostata. On the other hand, exposure of the mungbean Vigna radiata to the effluent revealed mostly no statistically significant adverse effect or growth stimulation. This suggested that on an exposure period of 96 h, higher forms of chlorophyll-bearing species such as plants are relatively unaffected by trace concentrations of PCBs and degradation products, while less differentiated species like algae and duckweeds are vulnerable.
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Affiliation(s)
- Dennis N Yu
- Chemical Engineering Department, De La Salle University - Manila, 2401 Taft Avenue, Malate, Manila 1004, Philippines.
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Dasary SSR, Saloni J, Fletcher A, Anjaneyulu Y, Yu H. Photodegradation of selected PCBs in the presence of Nano-TiO2 as catalyst and H2O2 as an oxidant. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2010; 7:3987-4001. [PMID: 21139872 PMCID: PMC2996220 DOI: 10.3390/ijerph7113987] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 10/25/2010] [Accepted: 11/12/2010] [Indexed: 01/11/2023]
Abstract
Photodegradation of five strategically selected PCBs was carried out in acetonitrile/water 80:20. Quantum chemical calculations reveal that PCBs without any chlorine on ortho-positions are closer to be planar, while PCBs with at least one chlorine atoms at the ortho-positions causes the two benzene rings to be nearly perpendicular. Light-induced degradation of planar PCBs is much slower than the perpendicular ones. The use of nano-TiO2 speeds up the degradation of the planar PCBs, but slows down the degradation of the non-planar ones. The use of H2O2 speeds up the degradation of planar PCBs greatly (by >20 times), but has little effect on non-planar ones except 2,3,5,6-TCB. The relative photodegradation rate is: 2,2′,4,4′-TCB > 2,3,5,6-TCB > 2,6-DCB ≈ 3,3′,4,4′-TCB > 3,4′,5-TCB. The use of H2O2 in combination with sunlight irradiation could be an efficient and “green” technology for PCB remediation.
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Affiliation(s)
- Samuel S R Dasary
- Department of Chemistry and Biochemistry, Jackson State University, 1400 J. R. Lynch Street, P.O. Box 17910, Jackson, MS 39217, USA.
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Monguchi Y, Ishihara S, Ido A, Niikawa M, Kamiya K, Sawama Y, Nagase H, Sajiki H. Pilot-Plant Study of the PCB Degradation at Ambient Temperature and Pressure. Org Process Res Dev 2010. [DOI: 10.1021/op100107r] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yasunari Monguchi
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Shinji Ishihara
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Akiko Ido
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Miki Niikawa
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Koichi Kamiya
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Yoshinari Sawama
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Hisamitsu Nagase
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
| | - Hironao Sajiki
- Laboratory of Organic Chemistry, Department of Organic and Medicinal Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, Laboratory of Hygienic Chemistry and Molecular Toxicology, Department of Biopharmaceutical Sciences, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan, and Ogaki Plant Sangyou, 3-38-1 Mangoku, Ogaki-shi, Gifu 503-0812, Japan
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Veriansyah B, Choi HM, Lee YW, Kang JW, Kim JD, Kim J. Continuous catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in transformer oil. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:1538-1544. [PMID: 20183511 DOI: 10.1080/10934520903263421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Continuous catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in the presence of transformer oils was carried out in a fixed bed reactor using a 57.6 wt% Ni on silicon oxide-aluminum oxide (SiO(2)-Al(2)O(3)) catalyst. Reaction temperatures ranging 150-300 degrees C, PCBs concentrations ranging 50-200 ppm, and reaction times ranging 1-8 h were tested. At a higher reaction temperature or at a lower PCBs concentration, catalytic activity was higher and complete dechlorination of PCBs resulted even at long reaction time. Catalyst regeneration using hexane and 0.1 M sodium hydroxide (NaOH) was effective to restore the catalytic activity. Fresh, spent and regenerated catalysts were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. XRD analysis revealed growth of Ni crystallite size of the spent and the regenerated catalysts. XPS analysis showed that a considerable amount of chlorine and carbon species were deposited on the surface of the spent catalyst, which may play a role in the catalysts deactivation.
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Affiliation(s)
- Bambang Veriansyah
- Energy and Environmental Research Division, Korea Institute of Science and Technology, Seoul, Korea
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Kubatova A. Critical factors in chemical characterization for the evaluation of decontamination in solids using advanced oxidation. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:1052-1068. [PMID: 19847695 DOI: 10.1080/10934520903005004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Advanced oxidation technologies (AOT) have been applied to the treatment of numerous organic pollutants embedded in solid matrices (e.g., soil, sediments, sludge, etc.). Given potentially strong matrix-analyte interactions in solids, chemical characterization of both the target contaminants and their oxidation products is critical for the evaluation of any decontamination method. The success of AOT applications has been evaluated either directly (based on the removal of original contaminants, extent of mineralization, and/or formation of by-products), or indirectly, e.g., based on toxicity or chemical oxygen demand. Since indirect methods do not provide comprehensive understanding of the pollutants' fate, direct analytical approaches are covered in this review while focusing on sample preparation and detailed chromatographic characterization, assessing the strengths and weaknesses of these methods. The significance of sample preparation, in particular extraction, is discussed with respect to the nature of matrix-analyte interactions, as those may also affect the selection of the remediation method. The ultimate goal of this review is the presentation of methods employed to achieve mass balance closure, which is essential to ensure the full understanding of degradation pathways.
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Affiliation(s)
- Alena Kubatova
- Chemistry Department, University of North Dakota, Grand Forks, North Dakota 58202, USA.
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Suh YW, Buettner GR, Venkataraman S, Treimer SE, Robertson LW, Ludewig G. UVA/B-induced formation of free radicals from decabromodiphenyl ether. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:2581-2588. [PMID: 19452920 PMCID: PMC2685467 DOI: 10.1021/es8022978] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Polybrominated diphenyl ether (PBDE) flame retardants are ubiquitous in the environment and in humans. A deca-bromodiphenyl ether mixture (deca-BDE) is the dominating commercial PBDE product today. Deca-BDE is degraded by UV to PBDEs with fewer bromines. We hypothesized that photodegradation of deca-BDE results in the formation of free radicals. We employed electron paramagnetic resonance (EPR) with spin trap agents to examine the free radicals formed from UV irradiation of a deca-BDE mixture (DE-83R). The activating wavelength for deca-BDE photochemistry was in the UVA to UVB range. The yields of radicals from irradiated deca-BDE in tetrahydrofuran, dimethylformamide, and toluene were about 9-, 4-, and 7-fold higher, respectively, than from irradiated solvent alone. Radical formation increased with deca-BDE concentration and irradiation time. The quantum yield of radical formation of the deca-BDE mixture was higher than with an octa-BDE mixture (DE-79; approximately 2-fold), decabromobiphenyl (PBB 209; approximately 2-fold), decachlorobiphenyl (PCB 209; approximately 3-fold), and diphenyl ether (DE; approximately 6-fold), indicating the positive effects of bromine and an ether bond on radical formation. Analysis of hyperfine splittings of the spin adducts suggests that radical formation is initiated or significantly enhanced by debromination paired with hydrogen abstraction from the solvents. To our knowledge this is the first study that uses EPR to demonstrate the formation of free radicals during the photolytic degradation of PBDEs. Our findings strongly suggestthe potential of negative consequences due to radical formation during UV exposure of PBDEs in biological systems.
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Affiliation(s)
- Yang-won Suh
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Garry R. Buettner
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA 52242, USA
- Free Radical and Radiation Biology Program, ESR Facility, The University of Iowa, Iowa City, IA 52242, USA
| | - Sujatha Venkataraman
- Free Radical and Radiation Biology Program, ESR Facility, The University of Iowa, Iowa City, IA 52242, USA
| | | | - Larry W. Robertson
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA 52242, USA
| | - Gabriele Ludewig
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA 52242, USA
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Choi HM, Veriansyah B, Kim J, Kim JD, Lee YW. Recycling of transformer oil contaminated by polychlorinated biphenyls (PCBs) using catalytic hydrodechlorination. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:494-501. [PMID: 19241263 DOI: 10.1080/10934520902719936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Catalytic hydrodechlorination of polychlorinated biphenyls (PCBs) in the presence of transformer oil was carried out in a batch mode to detoxify PCBs and to recycle the treated oil. Various metal supported catalysts, including 0.98 wt% Pt, 0.79 wt% Pd and 12.8 wt% Ni on gamma -alumina (gamma -Al(2)O(3)) support, and 57.6 wt% Ni on silicon oxide-aluminum oxide (SiO(2)-Al(2)O(3)) support were used for the hydrodechlorination. Metal particle size of the Pt catalyst was 2.0 nm and metal particle sizes of the Pd and Ni catalysts were in the range of 6.4-6.9 nm. Various supercritical fluids, supercritical carbon dioxide (scCO(2)), supercritical propane (scPropane), supercritical dimethyl ether (scDME) and supercritical isobutane (scIsobutane) were used as reaction media. PCBs conversion, dechlorination degree of PCBs, was measured using gas chromatograph (GC) with an electron capture detector (ECD). The hydrodechorination degree increased in the order Ni > Pd > Pt, possibly due to higher metal loading and larger metal size of the Ni catalysts. At temperatures below 175 degrees C, scCO(2) was effective as the reaction media for the catalytic hydrodechlorination of PCBs in the presence of the transformer oil. However, PCBs conversion decreased significantly when the hydrodechlorination was carried out in a homogeneous phase with using scPropane, scDME or scIsobutane as a reaction medium. This was attributed to dilution effect of the supercritical fluids. Molecular weights of the transformer oils before and after the catalytic hydrodechlorination were analyzed using high-performance size exclusion chromatography (HPSEC). The molecular weight of the treated oil with 100 % PCBs conversion did not change after the catalytic hydrodechlorination at 200 degrees C. This process has proven to be effective to detoxify PCBs containing transformer oil and to recycle the treated oil.
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Affiliation(s)
- Hye-Min Choi
- Supercritical Fluid Research Laboratory, Energy and Environmental Research Division, Korea Institute of Science and Technology (KIST), Seoul, Korea
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Li X, Fang L, Huang J, Yu G. Photolysis of mono- through deca-chlorinated biphenyls by ultraviolet irradiation in n-hexane and quantitative structure-property relationship analysis. J Environ Sci (China) 2008; 20:753-759. [PMID: 18763572 DOI: 10.1016/s1001-0742(08)62123-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The photolysis of 16 polychlorinated biphenyls (PCBs) (including mono- through deca-chlorinated) in n-hexane was investigated under ultraviolet irradiation using a 500-W high-pressure mercury lamp. Photolysis of PCBs follows pseudo-first-order reaction kinetics, with photolysis rate constants ranging between 0.0011 s(-1) for PCB-52 and 0.0574 s(-1) for PCB-118. The degradation rates of PCBs by high-pressure mercury lamp irradiation were remarkably independent with respect to the degree of chlorination. Furthermore, partial least squares (PLS) models were developed to provide insight into which aspect of the molecular structure influenced PCB photolysis rate constants. It was found that the photolysis rates of PCBs increased with an increase in the net charge on the carbon atom (qc), (E(LUMO)-E(HOMO))2, and the Y-axis dipole moment (mu(y)) values, or the decrease in the energy of the second highest occupied molecular orbital (E(HOMO-1)), energy of the lowest unoccupied molecular orbital (E(LUMO)), E(LUMO) + E(HOMO), E(LUMO)--E(HOMO), most positive atomic charge (q+), and the twist angle of the chlorine atom (TA) values.
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Affiliation(s)
- Xue Li
- POPs Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
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Centi S, Laschi S, Fránek M, Mascini M. A disposable immunomagnetic electrochemical sensor based on functionalised magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs). Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2005.01.073] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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