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Schröder S, Ortiz I, San-Román MF. Electrochemical degradation of key drugs to treat COVID-19: Experimental analysis of the toxic by-products formation (PCDD/Fs). THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167660. [PMID: 37813253 DOI: 10.1016/j.scitotenv.2023.167660] [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: 07/21/2023] [Revised: 10/05/2023] [Accepted: 10/05/2023] [Indexed: 10/11/2023]
Abstract
Drug consumption has grown exponentially in recent decades, particularly during the COVID-19 pandemic, leading to their presence in various water sources. In this way, degradation technologies for pollutants, such as electrochemical oxidation (ELOX), have become crucial to safeguard the quality of natural resources. This study has as its starting point a previous research, which demonstrated the efficacy of ELOX in the removal of COVID-19 related-drugs, such as dexamethasone (DEX), paracetamol (PAR), amoxicillin (AMX), and sertraline (STR), using the electrolytes NaCl and Na2SO4. The present research aims to study the potential risks associated with the generation of toxic by-products, during the ELOX of cited drugs, specifically focusing on the highly chlorinated persistent organic pollutants (POPs), such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Dioxins and furans can be formed potentially in electrochemical systems from precursor molecules or non-precursor molecules in chloride medium. First, the degradation of the parent compounds was found to be complete. At this point, a comprehensive investigation was conducted to identify and analyse the by-products formed during the degradation process; precursors of PCDD/Fs, such as chlorophenols or hydroquinones were identified. Additionally, in continuation of the previous study, PCDD/Fs congeners were investigated, revealing elevated concentrations; the highest concentration obtained was for the congener 1,2,3,4,6,7,8-HpCDF (234.6 pg L-1 in NaCl) during degradation of the AMX. Finally, an assessment of the toxicity based on TEQ values was conducted, with DEX exhibiting the highest concentration among all compounds: 30.1 pg L-1 for NaCl medium. Therefore, the formation of minor by-products should not be underestimated, as they can significantly enhance the toxicity of the final sample, so the selection of the appropriate remediation technology, as well as the optimization of experimental operating variables, is determining in the treatment of pharmaceutical-contaminated waters.
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Affiliation(s)
- Sophie Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Ma-Fresnedo San-Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
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Xie W, Li W, Wang P, Hao Y, Chen B, Hu L, Wang T, Zhang Q, Liang Y, Jiang G. Unexpected Dioxin Formation During Digestion of Soil with Oxidizing Acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14717-14725. [PMID: 37682840 DOI: 10.1021/acs.est.3c03682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
Dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), are among the most toxic unintentionally produced persistent organic pollutants, and their emission is of great concern. Herein, we discovered abundant dioxin formation in soil and various organic carbon-containing matrices after digestion with aqua regia. Σ17PCDD/Fs concentrations were in the range of 66.6-142,834 pg/g dw (5.6-17,021 pg WHO2005-TEQ/g dw) in 19 soil samples after digestion with aqua regia for 6 h. Σ17PCDD/Fs concentration was significantly and positively correlated with soil organic carbon content (R2 = 0.89; p < 0.01). Compared with cellulose and lignin, humic acid served as an important organic matter component that was converted to PCDD/Fs during soil digestion. Strong oxidation and production of reactive chlorine by aqua regia may be the key factors in the formation of PCDD/Fs. The yearly emission of PCDD/Fs due to digestion with strong acids by the inspection and testing industry was estimated to be 83.8 g TEQ in China in 2021 based on the highest level, which was ∼0.9% of the total dioxin inventory in China. Great attention should be paid to unexpected dioxin formation during digestion processes considering the potential risk of release from laboratories and enterprises.
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Affiliation(s)
- Wenjing Xie
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Wenjuan Li
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Pu Wang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Yanfen Hao
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Bolei Chen
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Thanh Wang
- Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping 58183, Sweden
- Department of Thematic Studies─Environmental Change (TemaM), Linköping University, Linköping 58183, Sweden
| | - Qinghua Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yong Liang
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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Schröder S, Ortiz I, San-Román MF. Formation of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in the electrochemical oxidation of polluted waters with pharmaceuticals used against COVID-19. JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 2023; 11:109305. [PMID: 36647535 PMCID: PMC9833857 DOI: 10.1016/j.jece.2023.109305] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/04/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
The COVID-19 pandemic has produced a huge impact on our lives, increasing the consumption of certain pharmaceuticals, and with this, contributing to the intensification of their presence in wastewater and in the environment. This situation demands the implementation of efficient remediation technologies, among them, electrochemical oxidation (ELOX) is one the most applied. This work studies the application of ELOX with the aim of eliminate pharmaceuticals used in the fight against COVID-19, assessing its degradation rate, as well as the risk of formation of toxic trace by-products, such as unintentional POPs like polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). To this end, model solutions containing 10 mg L-1 of dexamethasone (DEX), paracetamol (PAR), amoxicillin (AMX), and sertraline (STR) with two different electrolytes (NaCl and Na2SO4) have been evaluated. However, electrochemical systems that contain chloride ions in solution together with PCDD/Fs precursor molecules may lead to the formation of these highly toxic by-products. So, PCDD/Fs were quantified under conditions of complete degradation of the drugs. Furthermore, the presence of PCDD/Fs precursors such as chlorophenols was determined, as well as the role of Cl-, Cl• and SO 4 • - radicals in the formation of the by-products and PCDD/Fs. The maximum measured concentration of PCDD/Fs was around 2700 pg L-1 for the amoxicillin case in NaCl medium. The obtained results emphasise the importance of not underestimating the potential formation of these highly toxic trace by-products, in addition to the correct selection of oxidation processes and operation variables, in order to avoid final higher toxicity in the medium.
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Affiliation(s)
- Sophie Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros 46, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros 46, 39005 Santander, Spain
| | - Ma-Fresnedo San-Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros 46, 39005 Santander, Spain
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Tang B, Zou J, Wang X, Li B, Fu D, Thapa S, Sun X, Qi H. Theoretical insights into the gas/heterogeneous phase reactions of hydroxyl radicals with chlorophenols: Mechanism, kinetic and toxicity assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:150974. [PMID: 34656601 DOI: 10.1016/j.scitotenv.2021.150974] [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: 07/26/2021] [Revised: 09/16/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
Emission of 2-chlorophenols (2-CPs) can cause serious air pollution and health problems. Here, the reaction kinetics and products of key radicals in 2-CPs photo-oxidation are explored in both gaseous and heterogeneous reactions. Quantum chemical calculations show that •OH-addition pathways are more preferable than H-abstraction pathways in gas phase, while that is opposite in heterogeneous phase. At 298 K, the overall rate coefficients of the title reactions in gas and heterogeneous phases are 3.48 × 10-13 and 2.37 × 10-13 cm3 molecule-1 s-1 with half-lives of 55.3 h and 81.2 h, respectively. The strong H-bonds between linear Si3O2(OH)8 and 2-CPs change the energy barriers of initial •OH-addition and H-abstraction reactions, resulting in the competition between heterogeneous reactions and gas phase reactions. The products in heterogeneous reactions are chloroquinone and HONO, which can cause atmospheric acid deposition and eco-toxicity. In gas phase, self-cyclization of alkoxy radical (RO•) leads to formation of •HO2 and highly‑oxygenated molecules, which cause formation of secondary organic aerosol. It is emphasized that oxidation of 2-CPs by •OH leads to formation of more toxic products for aquatic organisms. Therefore, more attention should be focused on the products originated from •OH-initiated reactions of (2-)CPs in gaseous and heterogeneous reactions.
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Affiliation(s)
- Bo Tang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jinlong Zou
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University, Harbin, 150090, China
| | - Xueyu Wang
- Key Laboratory of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China
| | - Bo Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Donglei Fu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Samit Thapa
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiazhong Sun
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Hong Qi
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; School of Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory of Polar Environment and Ecosystem, Heilongjiang Province, Harbin 150090, China.
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Schröder S, San-Román MF, Ortiz I. Dioxins and furans toxicity during the photocatalytic remediation of emerging pollutants. Triclosan as case study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:144853. [PMID: 33513494 DOI: 10.1016/j.scitotenv.2020.144853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
The benefits of wastewater remediation technologies are offset in those cases where, as a result of operating conditions, harmful compounds are formed in the degradation routes of the original organic pollutants. This may be the case for the application of some advanced oxidation processes to wastewater containing precursors of dioxins and furans, as previously reported in the application of electrochemical and Fenton oxidation to degrade Triclosan and 2-chlorophenol. This work reports for the first time a detailed kinetic analysis of the formation of dioxins and furans during the photocatalytic treatment of aqueous samples containing 5-Chloro-2-[2,4-dichlorophenoxy] phenol, commercially known as Triclosan. After analysis of the PCDD/Fs concentration, the toxicity of the samples has been determined in terms of toxic equivalents (TEQ). TEQ values have been calculated, first with the group of 17 congeners with higher toxicity. Finally, a multivariable analysis and linear regression have been applied to reduce the significant number of congeners and optimize the analytical effort.
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Affiliation(s)
- Sophie Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Mª-Fresnedo San-Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
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Lei M, Gao Q, Zhou K, Gogoi P, Liu J, Wang J, Song H, Wang S, Liu X. Catalytic degradation and mineralization mechanism of 4-chlorophenol oxidized by phosphomolybdic acid/H2O2. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117933] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Popli SA, Patel P, Date M, Ruparelia J, Patel UD. Rapid electro-catalytic reduction of azo dyes and phenolic compounds in the presence of metallic palladium. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Abstract
5-Chloro-2-[2,4-dichlorophenoxy]-phenol, or triclosan (TCS), is an antimicrobial and antifungal agent with high resistance to conventional wastewater treatments, thus, more effective remediation technologies are necessary, where photocatalytic processes deserve special attention due to the high degradation rates of TCS, and the use of a renewable source of energy. However, different by-products may be formed during the treatment, sometimes more harmful than the parent compounds. Efforts to detail reaction pathways continually feed into related literature; however, knowing the transformation kinetics and the dependence on the operating variables is essential for the correct design of the abovementioned remediation technologies. This work contributes to increasing the knowledge necessary for the application of photocatalytic processes for the degradation of emerging pollutants, with TCS as a case study. First, an experimental plan to analyze the influence of the operating variables was carried out, determining time courses of the parent and intermediate compounds. Next, the kinetic model and parameters that are capable of predicting TCS concentration and its derivatives as a function of the operating conditions are provided. This constitutes a very useful tool to predict the performance of wastewater remediation treatment both in the degradation of the original pollutant and in the reduction of the toxicity in the treated water.
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Sun B, Li Q, Zheng M, Su G, Lin S, Wu M, Li C, Wang Q, Tao Y, Dai L, Qin Y, Meng B. Recent advances in the removal of persistent organic pollutants (POPs) using multifunctional materials:a review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114908. [PMID: 32540566 DOI: 10.1016/j.envpol.2020.114908] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 04/30/2020] [Accepted: 05/28/2020] [Indexed: 06/11/2023]
Abstract
Persistent organic pollutants (POPs) have gained heightened attentions in recent years owing to their persistent property and hazard influence on wild life and human beings. Removal of POPs using varieties of multifunctional materials have shown a promising prospect compared with conventional treatments. Herein, three main categories, including thermal degradation, electrochemical remediation, as well as photocatalytic degradation with the use of diverse catalytic materials, especially the recently developed prominent ones were comprehensively reviewed. Kinetic analysis and underlying mechanism for various POPs degradation processes were addressed in detail. The review also systematically documented how catalytic performance was dramatically affected by the nature of the material itself, the structure of target pollutants, reaction conditions and treatment techniques. Moreover, the future challenges and prospects of POPs degradation by means of multiple multifunctional materials were outlined accordingly. Knowing this is of immense significance to enhance our understanding of POPs remediation procedures and promote the development of novel multifunctional materials.
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Affiliation(s)
- Bohua Sun
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qianqian Li
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Minghui Zheng
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guijin Su
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Shijing Lin
- College of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing, 102617, PR China
| | - Mingge Wu
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chuanqi Li
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qingliang Wang
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuming Tao
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lingwen Dai
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yi Qin
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bowen Meng
- Key Laboratory of Environmental Nanotechnology and Health Effects, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco- Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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Yang Y, Wu G, Jiang C, Zheng M, Yang L, Xie J, Wang Q, Wang M, Li C, Liu G. Variations of PCDD/Fs emissions from secondary nonferrous smelting plants and towards to their source emission reduction. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 260:113946. [PMID: 32041007 DOI: 10.1016/j.envpol.2020.113946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/25/2019] [Accepted: 01/07/2020] [Indexed: 06/10/2023]
Abstract
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are cancerogenic organic pollutants that priority controlled by Stockholm Convention with globally 183 signatories now. Secondary nonferrous smelting plants are confirmed to be important sources in China due to its large industrial activities and high emissions of PCDD/Fs. It is important to prioritize source to achieve source emission reduction by conducting field monitoring on typical case plants. Here, the emission profiles and levels of PCDD/Fs were investigated in 25 stack gas samples collected from three secondary copper production (SeCu), two secondary zinc production (SeZn) and two secondary lead production (SePb). Both average mass concentration and toxic equivalency quantity (TEQ) concentrations of PCDD/Fs all generally decreased in the order: SeCu > SeZn > SePb. It is noteworthy that the mean TEQ concentration in stack gas from SeCu with oxygen-enrich melting furnace technology, at 2.7 ng I-TEQ/Nm3, was much higher than the concentrations of other smelting processes. The average emission factors and annual release amounts of PCDD/Fs from SeCu, SePb and SeZn investigated were 28.4, 1.5, 10.4 μg I-TEQ/t and 1.03, 0.023, 0.17 g I-TEQ/year, respectively. The ratios of 2,3,7,8-TCDF to 1,2,3,7,8-PeCDF and OCDD to 1,2,3,7,8,9-HxCDD varied to large extent for three metal smelting, which could be used as diagnostic ratios of tracing specific PCDD/Fs sources. Addition of copper-containing sludge into the raw materials might lead to higher PCDD/Fs emissions. It is important to emphasize and reduce the PCDD/Fs emissions from oxygen-enrich melting furnace from secondary copper productions.
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Affiliation(s)
- Yuanping Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guanglong Wu
- International Environmental Cooperation Center, Ministry of Ecology and Environment of People's Republic of China, Beijing, 100035, China
| | - Cheng Jiang
- International Environmental Cooperation Center, Ministry of Ecology and Environment of People's Republic of China, Beijing, 100035, China
| | - Minghui Zheng
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lili Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiahong Xie
- International Environmental Cooperation Center, Ministry of Ecology and Environment of People's Republic of China, Beijing, 100035, China
| | - Qingjie Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China
| | - Minxiang Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China
| | - Cui Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guorui Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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11
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Solá-Gutiérrez C, Schröder S, San-Román MF, Ortiz I. Critical review on the mechanistic photolytic and photocatalytic degradation of triclosan. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 260:110101. [PMID: 32090818 DOI: 10.1016/j.jenvman.2020.110101] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/11/2019] [Accepted: 01/06/2020] [Indexed: 06/10/2023]
Abstract
The environmentally extended presence of triclosan, TCS, component of many pharmaceutical and personal care products, and its known persistent character have awoke the scientific and social concern leading to the study of effective remediation techniques. Advanced oxidation techniques stand out for the effectiveness in degrading many persistent compounds, and as a result, they have been addressed by many researchers. However, the powerful oxidation media might lead to the formation of undesirable by-products, concern that has also been widely addressed. With regard to the presence of TCS, photolytic and photocatalytic processes provide a very effective degradation yield and rate, with a large number of reports addressing its removal from different environmental matrices. But currently, there is no clear understanding of the mechanisms involved and the routes responsible for the formation of degradation products. Thus, this work presents an exhaustive and critical analysis of the state of the art related to the photo-degradation of TCS, with special focus on the formation of oxidation by-products, on the phenomena responsible and on the influence of operation variables. This report aims at offering valuable information to researchers dealing with this environmentally relevant problem.
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Affiliation(s)
- Claudia Solá-Gutiérrez
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - Sophie Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - M Fresnedo San-Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain.
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San-Román MF, Solá-Gutiérrez C, Schröder S, Laso J, Margallo M, Vázquez-Rowe I, Ortiz I, Irabien A, Aldaco R. Potential formation of PCDD/Fs in triclosan wastewater treatment: An overall toxicity assessment under a life cycle approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:135981. [PMID: 31869605 DOI: 10.1016/j.scitotenv.2019.135981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Wastewater may contain a diverse group of unregulated pollutants known as emerging pollutants, such as pharmaceuticals and personal care products (PPCPs). Triclosan (TCS) is a personal care product widely used as an antiseptic or preservative in cosmetics, hand wash, toothpaste and deodorant soaps. Advanced oxidation processes (AOPs) have been used as effective and alternative treatments for complex wastewater. However, an important criterion for the assessment of AOPs and their operation conditions could be the potential formation of new toxic secondary products, such as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), especially when emerging pollutants are present in the media. If these are omitted from environmental management studies, the real environmental impacts of a WWTPs (wastewater treatment plants) may be underestimated. Consequently, the current study aims to evaluate the environmental impacts derived from electrooxidation (EOX), one of the most effective oxidation technologies, of emerging pollutants using Life Cycle Assessment. The analyses were performed for the treatment of effluents containing TCS, firstly without considering the formation of PCDD/Fs and, thereafter, considering the effects of these compounds. Total toxicity, calculated through different methods and corresponding impact factors, were evaluated for each stage of the process when different electrolytes are used, including PCDD/Fs formation. Finally, a sensitivity analysis was carried out to study i) the effect of the TCS initial concentration on the environmental impacts associated to ecotoxicity for the different life cycle methods and ii) the influence of changing the organic pollutant on PCDD/Fs formation employing 2-chlorophenol (2-CP). As a result, LCIA methods demonstrate that they are not fully adapted to the computation of PCDD/Fs in the water compartment, since only 2,3,7,8-tetraclorodibenzo-p-dioxina (2,3,7,8-TCDD) is present as a substance in the impact categories assessed, ignoring the remaining list of PCDD/Fs.
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Affiliation(s)
- M F San-Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
| | - C Solá-Gutiérrez
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - S Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - J Laso
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - M Margallo
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - I Vázquez-Rowe
- Peruvian Life Cycle Assessment Network (PELCAN), Departamento de Ingeniería, Pontificia Universidad Católica del Perú, Av. Universitaria 1801, San Miguel, Lima 15088, Peru
| | - I Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - A Irabien
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - R Aldaco
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
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13
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Brüninghoff R, van Duijne AK, Braakhuis L, Saha P, Jeremiasse AW, Mei B, Mul G. Comparative Analysis of Photocatalytic and Electrochemical Degradation of 4-Ethylphenol in Saline Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8725-8735. [PMID: 31282148 PMCID: PMC6686150 DOI: 10.1021/acs.est.9b01244] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 07/03/2019] [Accepted: 07/08/2019] [Indexed: 06/03/2023]
Abstract
We evaluated electrochemical degradation (ECD) and photocatalytic degradation (PCD) technologies for saline water purification, with a focus on rate comparison and formation and degradation of chlorinated aromatic intermediates using the same non-chlorinated parent compound, 4-ethylphenol (4EP). At 15 mA·cm-2, and in the absence of chloride (0.6 mol·L-1 NaNO3 was used as supporting electrolyte), ECD resulted in an apparent zero-order rate of 30 μmol L-1·h-1, whereas rates of ∼300 μmol L-1·h-1 and ∼3750 μmol L-1·h-1 were computed for low (0.03 mol·L-1) and high (0.6 mol·L-1) NaCl concentration, respectively. For PCD, initial rates of ∼330 μmol L-1·h-1 and 205 μmol L-1·h-1 were found for low and high NaCl concentrations, at a photocatalyst (TiO2) concentration of 0.5 g·L-1, and illumination at λmax ≈ 375 nm, with an intensity ∼0.32 mW·cm-2. In the chlorine mediated ECD approach, significant quantities of free chlorine (hypochlorite, Cl2) and chlorinated hydrocarbons were formed in solution, while photocatalytic degradation did not show the formation of free chlorine, nor chlorine-containing intermediates, and resulted in better removal of non-purgeable hydrocarbons than ECD. The origin of the minimal formation of free chlorine and chlorinated compounds in photocatalytic degradation is discussed based on photoelectrochemical results and existing literature, and explained by a chloride-mediated surface-charge recombination mechanism.
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Affiliation(s)
- Robert Brüninghoff
- PhotoCatalytic
Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science
and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Alyssa K. van Duijne
- PhotoCatalytic
Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science
and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Lucas Braakhuis
- PhotoCatalytic
Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science
and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Pradip Saha
- Department
of Environmental Technology, Wageningen
University and Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Adriaan W. Jeremiasse
- MAGNETO
Special Anodes B.V. (an Evoqua brand), Calandstraat 109, 3125 BA Schiedam, The Netherlands
| | - Bastian Mei
- PhotoCatalytic
Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science
and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Guido Mul
- PhotoCatalytic
Synthesis Group, MESA+ Institute for Nanotechnology, Faculty of Science
and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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14
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Zhang C, Dong J, Liu M, Zhao W, Fu D. The role of nitrite in electrocatalytic oxidation of phenol: An unexpected nitration process relevant to groundwater remediation with boron-doped diamond electrode. JOURNAL OF HAZARDOUS MATERIALS 2019; 373:547-557. [PMID: 30951999 DOI: 10.1016/j.jhazmat.2019.03.118] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 03/21/2019] [Accepted: 03/27/2019] [Indexed: 06/09/2023]
Abstract
Using boron-doped diamond (BDD) to mineralize recalcitrant organics has been one of the hottest areas of research interest in the field of water treatment. Here we report for the first time that, in the presence of nitrite ions (NO2-), the anodic oxidation of phenol with BDD electrode will lead to the formation of nitrated by-products of phenol. These by-products include 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2,6-dinitrophenol, 2,4,6-trinitrophenol, 2,3,4,6-tetranitrophenol, 2,3,4,5,6-pentanitrophenol, as well as a large number of dimers and trimers of nitrophenols. Increasing the concentration of NO2- will not only greatly affects the degradation and mineralization of phenol, but also enhances the formation of nitrophenols. The nitrated by-products are mainly generated via electrophilic substitution reactions mediated by nitrogen dioxide radicals and hydroxyl radicals, as well as via coupling reactions of phenol. In addition, it is found that several simple nitrophenols may also be formed in nitrate media. As a whole, formation of nitrated by-products is a novel phenomenon in anodic oxidation processes. Since nitrated aromatics are well known for their persistence in the environment, their formations in BDD anode cells should be carefully scrutinized before such technology is applied to groundwater remediation.
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Affiliation(s)
- Chunyong Zhang
- Department of Chemistry, College of Science, Nanjing Agricultural University, Nanjing, 210095, China; State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, China.
| | - Jiayue Dong
- Department of Chemistry, College of Science, Nanjing Agricultural University, Nanjing, 210095, China
| | - Min Liu
- Department of Chemistry, College of Science, Nanjing Agricultural University, Nanjing, 210095, China
| | - Wenjia Zhao
- Department of Chemistry, College of Science, Nanjing Agricultural University, Nanjing, 210095, China
| | - Degang Fu
- State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, China
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15
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Solá-Gutiérrez C, Schröder S, San Román MF, Ortiz I. PCDD/Fs traceability during triclosan electrochemical oxidation. JOURNAL OF HAZARDOUS MATERIALS 2019; 369:584-592. [PMID: 30818123 DOI: 10.1016/j.jhazmat.2019.02.066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/13/2019] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
5-Chloro-2-(2,4-dichlorophenoxy)phenol (TCS) is a persistent organic pollutant (POP) widely used in different consumer goods. Its recalcitrant nature demands the application of effective remediation technologies in order to avoid the negative environmental impact associated to the discharge of contaminated waters. Although advanced oxidation technologies have been considered the best alternative to destroy bio-recalcitrant compounds, the likely formation of high toxicity byproducts must be analysed before large-scale deployment. In this work, we aim to trace the presence of chlorinated compounds during the electro-oxidation of aqueous TCS samples. First, we analyze the influence of the initial concentration of TCS on the toxicity of the oxidation medium expressed by the International-Toxicity Equivalency Factor (I-TEF); second, we have detected the formation of intermediate organo-chlorinated compounds by GC-MS supported by HPLC and finally, we have quantified the concentration of highly-polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by HRGC-HRMS within the oxidation treatment. In those samples where TCS had been completely degraded the concentration of PCDD/Fs showed a high increase, especially when NaCl was used as electrolyte, with the initial concentration of TCS. Under these conditions the I-TEF achieved values up to 3.8 × 102 pg L-1.
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Affiliation(s)
- Claudia Solá-Gutiérrez
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - Sophie Schröder
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain.
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16
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Zhang M, Shi Q, Song X, Wang H, Bian Z. Recent electrochemical methods in electrochemical degradation of halogenated organics: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:10457-10486. [PMID: 30798495 DOI: 10.1007/s11356-019-04533-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 02/07/2019] [Indexed: 06/09/2023]
Abstract
Halogenated organics are widely used in modern industry, agriculture, and medicine, and their large-scale emissions have led to soil and water pollution. Electrochemical methods are attractive and promising techniques for wastewater treatment and have been developed for degradation of halogenated organic pollutants under mild conditions. Electrochemical techniques are classified according to main reaction pathways: (i) electrochemical reduction, in which cleavage of C-X (X = F, Cl, Br, I) bonds to release halide ions and produce non-halogenated and non-toxic organics and (ii) electrochemical oxidation, in which halogenated organics are degraded by electrogenerated oxidants. The electrode material is crucial to the degradation efficiency of an electrochemical process. Much research has therefore been devoted to developing appropriate electrode materials for practical applications. This paper reviews recent developments in electrode materials for electrochemical degradation of halogenated organics. And at the end of this paper, the characteristics of new combination methods, such as photocatalysis, nanofiltration, and the use of biochemical method, are discussed.
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Affiliation(s)
- Meng Zhang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China
| | - Qin Shi
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China
- School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning, 530008, People's Republic of China
| | - Xiaozhe Song
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China
| | - Hui Wang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, People's Republic of China.
| | - Zhaoyong Bian
- College of Water Sciences, Beijing Normal University, Beijing, 100875, Beijing, People's Republic of China.
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17
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Lin S, Du W, Tong L, Ji T, Jiao X. Photocatalytic Degradation of 4-Chlorophenol by Gd-Doped β-Bi2O3 Under Visible Light Irradiation. Chem Res Chin Univ 2018. [DOI: 10.1007/s40242-018-8170-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Solá-Gutiérrez C, San Román MF, Ortiz I. Fate and hazard of the electrochemical oxidation of triclosan. Evaluation of polychlorodibenzo‑p‑dioxins and polychlorodibenzofurans (PCDD/Fs) formation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 626:126-133. [PMID: 29335167 DOI: 10.1016/j.scitotenv.2018.01.082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/22/2017] [Accepted: 01/09/2018] [Indexed: 06/07/2023]
Abstract
Triclosan (TCS) is widely used as antiseptic or preservative in many personal care products (PCPs), such as cosmetics, hand wash, toothpaste and deodorant soaps, among others. It is characterized by acute toxicity, resistance to biodegradation, environmental persistence and relatively high lipophilicity. In order to protect the environment and natural resources from the negative effects of the discharge of polluted wastewater with TCS, the application of efficient remediation technologies able to degrade the pollutant to harmless levels becomes crucial. Electrochemical oxidation, among all advanced oxidation processes (AOPs), has been reported as very effective in the complete degradation of a number of persistent pollutants; therefore, its performance using boron-doped diamond (BDD) anodes, and response to operation variables, has been studied in this work. As expected, complete degradation of TCS was achieved in all the studied conditions; however, going a step further and knowing that TCS is a precursor of polychlorinated dibenzo‑p‑dioxins and dibenzofurans (PCDD/Fs), their quantitative presence in the oxidation media has been assessed. Results showed the dominance of dichlorinated (DCDD) and trichlorinated (TrCDD/Fs) in the homologue profile of total PCDD/Fs, reaching values up to 1.48 × 105 pg L-1 in samples with initial concentration of TCS of 100 mg L-1 and NaCl as electrolyte. Under these conditions, the International Toxicity Equivalency Factor (I-TEF) achieved values up to 2.76 × 102 pg L-1. Nevertheless, the presence of copper in the oxidation medium tends to reduce I-TEF values. Finally, considering the information reported in literature, a mechanism describing the formation of low chlorinated PCDD/Fs from TCS oxidation reactions is proposed.
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Affiliation(s)
- Claudia Solá-Gutiérrez
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
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19
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Dai C, Zhou Y, Peng H, Huang S, Qin P, Zhang J, Yang Y, Luo L, Zhang X. Current progress in remediation of chlorinated volatile organic compounds: A review. J IND ENG CHEM 2018. [DOI: 10.1016/j.jiec.2017.12.049] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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20
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Sun Q, Li J, Le T, Zhang L. A Novel Voltammetric Sensor Based on Reduced Graphene Oxide-Platinum Nanohybrid-modified Electrode for Facile and Effective Determination of 4-Chlorophenol in Real Water Samples. B KOREAN CHEM SOC 2018. [DOI: 10.1002/bkcs.11439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Qi Sun
- College of Life Sciences; Chongqing Normal University; Chongqing 401331 China
| | - Jianmei Li
- Chongqing Vocational College of Light Industry; Chongqing 400065 China
| | - Tao Le
- College of Life Sciences; Chongqing Normal University; Chongqing 401331 China
| | - Lei Zhang
- College of Life Sciences; Chongqing Normal University; Chongqing 401331 China
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21
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Wu X, Zheng M, Zhao Y, Yang H, Yang L, Jin R, Xu Y, Xiao K, Liu W, Liu G. Thermochemical formation of polychlorinated dibenzo-p-dioxins and dibenzofurans on the fly ash matrix from metal smelting sources. CHEMOSPHERE 2018; 191:825-831. [PMID: 29080543 DOI: 10.1016/j.chemosphere.2017.10.103] [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: 08/23/2017] [Revised: 10/12/2017] [Accepted: 10/17/2017] [Indexed: 06/07/2023]
Abstract
Metal smelting processes are important sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The present work aims to clarify the formation characteristics of PCDD/Fs by heterogeneous mechanisms on fly ash from typical multiple secondary aluminum (SAl), secondary lead (SPb) smelting, and iron ore sintering (SNT) sources in China. The formation characteristics of PCDD/Fs on fly ash were studied in the temperature range 250-450 °C for 10-150 min. Substantial thermochemical formation of PCDD/Fs on SAl and SNT ash was observed. The maximum increase of PCDD/F concentrations under 350 °C for 30 min was 604 times greater than the initial concentration in SAl ash. The concentration of PCDD/Fs was 77 times greater than that of SNT fly ash under 350 °C for 30 min. However, the maximum increase of PCDD/F concentrations was less than 8 times that in raw SPb ash under 350 °C. Contents of total organic carbon (TOC), Cu, Al, Zn and Cl, which are widely recognized as important elements for promoting PCDD/F formation, were obviously higher in SAl and SNT ash than in SPb ash. This may explain the greater observed formation times of PCDD/Fs on SAl and SNT ash than that on SPb ash. It was found that several congeners tended to form at higher temperatures than those for SAl ash. Activation energy calculation according to the Arrhenius equations could explain the dominant formation of those congeners at much higher temperatures on SAl ash.
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Affiliation(s)
- Xiaolin Wu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Minghui Zheng
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuyang Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongbo Yang
- Guizhou Academy of Testing and Analysis, Guiyang, 550008, China
| | - Lili Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Rong Jin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yang Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ke Xiao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China
| | - Wenbin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guorui Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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22
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Escudero CJ, Iglesias O, Dominguez S, Rivero MJ, Ortiz I. Performance of electrochemical oxidation and photocatalysis in terms of kinetics and energy consumption. New insights into the p-cresol degradation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 195:117-124. [PMID: 27157700 DOI: 10.1016/j.jenvman.2016.04.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/20/2016] [Accepted: 04/24/2016] [Indexed: 05/11/2023]
Abstract
This work reports the comparative performance of two Advanced Oxidation Processes (AOPs), electrochemical oxidation and photocatalysis, as individual technological alternatives for the treatment of effluents containing p-cresol. First, the influence of operating parameters in the oxidation and mineralization yield was carried out together with kinetic analysis. Boron Doped Diamond (BDD), RuO2 and Pt as anodic materials, Na2SO4 and NaCl as supporting electrolytes and different current densities were evaluated in electrochemical oxidation whereas the effect of TiO2 concentration and radiation was studied in the photocatalytic degradation. Then, the parameter Electrical Energy per Order (EEO) was calculated to compare the energy consumption in both AOPs, concluding that under the studied conditions the electrochemical treatment with BDD, Na2SO4 and 125 A m-2 showed the best energy efficiency, with an EEO of 5.83 kW h m-3 order-1 for p-cresol and 58.05 kW h m-3 order-1 for DOC removal, respectively.
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Affiliation(s)
- Carlos J Escudero
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005, Santander, Spain
| | - Olalla Iglesias
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005, Santander, Spain
| | - Sara Dominguez
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005, Santander, Spain
| | - Maria J Rivero
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005, Santander, Spain
| | - Inmaculada Ortiz
- Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005, Santander, Spain.
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23
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Fernández-Castro P, San Román MF, Ortiz I. Theoretical and experimental formation of low chlorinated dibenzo-p-dioxins and dibenzofurans in the Fenton oxidation of chlorophenol solutions. CHEMOSPHERE 2016; 161:136-144. [PMID: 27424055 DOI: 10.1016/j.chemosphere.2016.07.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/15/2016] [Accepted: 07/04/2016] [Indexed: 06/06/2023]
Abstract
The formation of chlorinated and non-chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) has been experimentally investigated after the Fenton oxidation of 2-chlorophenol (2-CP, 15.56 mM) aqueous solutions by assessing the influence of iron concentration (0.09-2.88 mM), hydrogen peroxide dose (40.44-202.20 mM), temperature (20-70 °C) and chloride concentration (0-56.35 mM). The presence of chloride in the medium together with room temperature and substoichiometric Fenton conditions (40.44 mM H2O2) led to an increase in total PCDD/Fs concentration from less than 1 ng L(-1) to 2 μg L(-1). Results showed a dominance of the dichlorinated species (DCDD/Fs) in the homologue profile of total PCDD/Fs reaching values up to 1.5 μg L(-1). Furthermore, the products distribution exhibited a gradual decrease in the homologue concentration as the chlorination degree increased from di-to octachloro-substituted positions. Considering the characteristics of the reaction medium, the experimental results, and the information gathered in bibliography with regard to the generation of active radicals from 2-chlorophenol, a mechanism describing the formation of low chlorinated PCDD/Fs in a Fenton oxidizing aqueous system has been proposed.
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Affiliation(s)
- Pablo Fernández-Castro
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005, Santander, Spain.
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Arellano-González MÁ, González I, Texier AC. Mineralization of 2-chlorophenol by sequential electrochemical reductive dechlorination and biological processes. JOURNAL OF HAZARDOUS MATERIALS 2016; 314:181-187. [PMID: 27131458 DOI: 10.1016/j.jhazmat.2016.04.048] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 04/15/2016] [Accepted: 04/19/2016] [Indexed: 06/05/2023]
Abstract
In this work, a novel approach was applied to obtain the mineralization of 2-chlorophenol (2-CP) in an electrochemical-biological combined system where an electrocatalytic dehydrogenation process (reductive dechlorination) was coupled to a biological denitrification process. Reductive dechlorination of 2-CP was conducted in an ECCOCEL-type reactor on a Pd-Ni/Ti electrode at a potential of -0.40V vs Ag/AgCl(s)/KCl(sat), achieving 100 percent transformation of 2-CP into phenol. The electrochemically pretreated effluent was fed to a rotating cylinder denitrifying bioreactor where the totality of phenol was mineralized by denitrification, obtaining CO2 and N2 as the end products. The total time required for 2-CP mineralization in the combined electrochemical-biological process was 7.5h. This value is close to those previously reported for electrochemical and advanced oxidation processes but in this case, an efficient process was obtained without accumulation of by-products or generation of excessive energy costs due to the selective electrochemical pretreatment. This study showed that the use of electrochemical reductive pretreatment combined with biological processes could be a promising technology for the removal of recalcitrant molecules, such as chlorophenols, from wastewaters by more efficient, rapid, and environmentally friendly processes.
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Affiliation(s)
- Miguel Ángel Arellano-González
- Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D.F., Mexico
| | - Ignacio González
- Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Química, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D.F., Mexico
| | - Anne-Claire Texier
- Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Biotecnología, Av. San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico, D.F., Mexico.
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Verlato E, He W, Amrane A, Barison S, Floner D, Fourcade F, Geneste F, Musiani M, Seraglia R. Preparation of Silver-Modified Nickel Foams by Galvanic Displacement and Their Use as Cathodes for the Reductive Dechlorination of Herbicides. ChemElectroChem 2016. [DOI: 10.1002/celc.201600214] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Wenyan He
- Université de Rennes 1; CNRS, UMR 6226; Equipe Matière Condensée et Systèmes Electroactifs; Campus de Beaulieu; 35042 Rennes Cedex France
- Ecole Nationale Supérieure de Chimie de Rennes; Université de Rennes 1; CNRS, UMR 6226; 11 allée de Beaulieu, CS 50837 35708 Rennes cedex 7 France
| | - Abdeltif Amrane
- Ecole Nationale Supérieure de Chimie de Rennes; Université de Rennes 1; CNRS, UMR 6226; 11 allée de Beaulieu, CS 50837 35708 Rennes cedex 7 France
| | | | - Didier Floner
- Université de Rennes 1; CNRS, UMR 6226; Equipe Matière Condensée et Systèmes Electroactifs; Campus de Beaulieu; 35042 Rennes Cedex France
| | - Florence Fourcade
- Ecole Nationale Supérieure de Chimie de Rennes; Université de Rennes 1; CNRS, UMR 6226; 11 allée de Beaulieu, CS 50837 35708 Rennes cedex 7 France
| | - Florence Geneste
- Université de Rennes 1; CNRS, UMR 6226; Equipe Matière Condensée et Systèmes Electroactifs; Campus de Beaulieu; 35042 Rennes Cedex France
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Wang L, Sun Q, Liu Y, Lu Z. Voltammetric determination of 4-chlorophenol using multiwall carbon nanotube/gold nanoparticle nanocomposite modified glassy carbon electrodes. RSC Adv 2016. [DOI: 10.1039/c6ra02385a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We synthesized gold nanoparticles/carboxyl functionalized multi-walled carbon nanotubes nanocomposites via an in situ reduction method and further explored their potentials in 4-chlorophenol detection.
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Affiliation(s)
- Ling Wang
- Institute for Clean Energy & Advanced Materials
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
| | - Qi Sun
- Institute for Clean Energy & Advanced Materials
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
| | - Yang Liu
- Institute of Food Science and Technology
- Chinese Academy of Agricultural Sciences
- Beijing 100193
- P. R. China
| | - Zhisong Lu
- Institute for Clean Energy & Advanced Materials
- Faculty of Materials & Energy
- Southwest University
- Chongqing 400715
- P. R. China
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27
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Electrochemical oxidative dimerization of monobrominated phenols and pentabromophenol in methanol-aqueous media. MONATSHEFTE FUR CHEMIE 2015. [DOI: 10.1007/s00706-015-1597-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Vallejo M, Fernández-Castro P, San Román MF, Ortiz I. Assessment of PCDD/Fs formation in the Fenton oxidation of 2-chlorophenol: Influence of the iron dose applied. CHEMOSPHERE 2015; 137:135-141. [PMID: 26134538 DOI: 10.1016/j.chemosphere.2015.06.056] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 06/14/2015] [Accepted: 06/20/2015] [Indexed: 06/04/2023]
Abstract
Toxic polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) may be formed during remediation of chlorinated phenols via Fenton oxidation. To highlight the need for monitoring the production of toxic byproducts in these reactions, this work assessed the influence of iron dose (0.09-0.36 mM) on the Fenton oxidation of 2-chlorophenol (2-CP, 15.56 mM), a potential precursor of PCDD/Fs, by quantifying 2-CP removal and mineralization rates as well as byproducts yields, including PCDD/Fs. Although the increase in the iron dose showed positive contribution to 2-CP oxidation, under the operating conditions of the current study (H2O2 at 20% of the stoichiometric dose and 20 °C), there was no effect on the mineralization rate, and TOC and chlorine balances were far to be closed, depicting the presence of chlorinated organic byproducts in the reaction medium. After 4 h of treatment, the total PCDD/Fs concentrations increased by 14.5-39 times related to the untreated sample when the iron doses tested decreased from 0.36 to 0.09 mM, with preferential formation of PCDFs over PCDDs and dominance of lower chlorinated congeners such as tetra and penta-PCDD/Fs. The treatment with the highest iron dose (0.36 mM) exhibited the lowest PCDD/Fs yields and was thus most successful at mitigating toxic byproducts of the Fenton oxidation, leading to lower sample toxic equivalence (TEQ) value.
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Affiliation(s)
- Marta Vallejo
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Pablo Fernández-Castro
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
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Zhang Q, Guo X, Cao X, Wang D, Wei J. Facile preparation of a Ti/α-PbO2/β-PbO2 electrode for the electrochemical degradation of 2-chlorophenol. CHINESE JOURNAL OF CATALYSIS 2015. [DOI: 10.1016/s1872-2067(15)60851-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Sun Z, Zhang H, Wei X, Ma X, Hu X. Preparation and electrochemical properties of SnO2-Sb-Ni-Ce oxide anode for phenol oxidation. J Solid State Electrochem 2015. [DOI: 10.1007/s10008-015-2892-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Qi C, Liu X, Zhao W, Lin C, Ma J, Shi W, Sun Q, Xiao H. Degradation and dechlorination of pentachlorophenol by microwave-activated persulfate. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:4670-4679. [PMID: 25328098 DOI: 10.1007/s11356-014-3718-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/10/2014] [Indexed: 06/04/2023]
Abstract
The degradation performance of pentachlorophenol (PCP) by the microwave-activated persulfate (MW/PS) process was investigated in this study. The results indicated that degradation efficiency of PCP in the MW/PS process followed pseudo-first-order kinetics, and compared with conventional heating, microwave heating has a special effect of increasing the reaction rate and reducing the process time. A higher persulfate concentration and reaction temperature accelerated the PCP degradation rate. Meanwhile, increasing the pH value and ionic strength of the phosphate buffer slowed down the degradation rate. The addition of ethanol and tert-butyl alcohol as hydroxyl radical and sulfate radical scavengers proved that the sulfate radicals were the dominant active species in the MW/PS process. Gas chromatography-mass spectrometry (GC-MS) was employed to identify the intermediate products, and then a plausible degradation pathway involving dechlorination, hydrolysis, and mineralization was proposed. The acute toxicity of PCP, as tested with Photobacterium phosphoreum, Vibrio fischeri, and Vibrio qinghaiensis, was negated quickly during the MW/PS process, which was in agreement with the nearly complete mineralization of PCP. These results showed that the MW/PS process could achieve a high mineralization level in a short time, which provided an efficient way for PCP elimination from wastewater.
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Affiliation(s)
- Chengdu Qi
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
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Li J, Yang J, Liu YY, Ma JF. Two Heterometallic-Organic Frameworks Composed of Iron(III)-Salen-Based Ligands and d10Metals: Gas Sorption and Visible-Light Photocatalytic Degradation of 2-Chlorophenol. Chemistry 2015; 21:4413-21. [DOI: 10.1002/chem.201406349] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Indexed: 11/09/2022]
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Vallejo M, Fresnedo San Román M, Ortiz I, Irabien A. Overview of the PCDD/Fs degradation potential and formation risk in the application of advanced oxidation processes (AOPs) to wastewater treatment. CHEMOSPHERE 2015; 118:44-56. [PMID: 24974140 DOI: 10.1016/j.chemosphere.2014.05.077] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/23/2014] [Accepted: 05/26/2014] [Indexed: 06/03/2023]
Abstract
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are a family of unintentionally produced persistent organic pollutants (POPs) that have received considerable public and scientific attention due to the toxicity of some of their congeners, more specifically those with chlorine substitution in the 2,3,7,8 positions. The environmental management and control of PCDD/Fs is addressed at a global level through the Stockholm Convention that establishes that POPs should be destroyed or irreversibly transformed in order to reduce or eliminate their release to the environment. Several technologies, including advanced oxidation processes (AOPs) such as photolysis, photocatalysis and Fenton oxidation, have been considered as effective methods for destroying PCDD/Fs in polluted waters. Nevertheless, during the remediation of wastewaters it is critical that the treatment technologies applied do not lead to the formation of by-products that are themselves POPs, especially if PCDD/Fs precursors or chlorine are present in the reaction medium. Despite the high effectiveness of AOPs in the oxidation of major contaminants, scarce references deal with the monitoring of PCDD/Fs in the course of the oxidation process, revealing that a detailed assessment of non-combustion technologies with respect to PCDD/Fs formation is still lacking. This study reports a review of the state of the art related to the potential remediation and/or formation of PCDD/Fs as a result of the application of AOPs for the treatment of polluted waters, warning on the correct selection of the operating conditions.
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Affiliation(s)
- Marta Vallejo
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
| | - Angel Irabien
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
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Chen L, Campo P, Kupferle MJ. Identification of chlorinated oligomers formed during anodic oxidation of phenol in the presence of chloride. JOURNAL OF HAZARDOUS MATERIALS 2014; 283:574-581. [PMID: 25464298 DOI: 10.1016/j.jhazmat.2014.10.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/16/2014] [Accepted: 10/01/2014] [Indexed: 06/04/2023]
Abstract
Chlorinated oligomer intermediates formed during the anodic electrochemical oxidation of phenol with a boron-doped diamond electrode were studied at two different concentrations of chloride (5mM and 50mM). Under the same ionic strength, with sodium sulfate being the make-up ion, a 10-fold increase in Cl(-) led to removal rates 10.8, 1.5, and 1.4 times higher for phenol, TOC, and COD, respectively. Mono-, di- and trichlorophenols resulting from electrophilic substitution were the identified by-products. Nevertheless, discrepancies between theoretical and measured TOC values along with gaps in the mass balance of chlorine-containing species indicated the formation of unaccounted-for chlorinated by-products. Accurate mass measurements by liquid chromatography quadrupole time-of-flight mass spectrometry and MS-MS fragmentation spectra showed that additional compounds formed were dimers and trimers of phenol with structures similar to triclosan and polychlorinated dibenzo-p-dioxins.
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Affiliation(s)
- Linxi Chen
- Department of Biomedical, Chemical and Environmental Engineering, University of Cincinnati, 701B ERC building, 2901 Woodside Dr., Cincinnati, OH 45221, United States
| | - Pablo Campo
- Department of Biomedical, Chemical and Environmental Engineering, University of Cincinnati, 701B ERC building, 2901 Woodside Dr., Cincinnati, OH 45221, United States
| | - Margaret J Kupferle
- Department of Biomedical, Chemical and Environmental Engineering, University of Cincinnati, 701B ERC building, 2901 Woodside Dr., Cincinnati, OH 45221, United States.
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Vallejo M, San Román MF, Ortiz I, Irabien A. The critical role of the operating conditions on the Fenton oxidation of 2-chlorophenol: assessment of PCDD/Fs formation. JOURNAL OF HAZARDOUS MATERIALS 2014; 279:579-585. [PMID: 25113517 DOI: 10.1016/j.jhazmat.2014.07.020] [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: 04/25/2014] [Revised: 06/25/2014] [Accepted: 07/13/2014] [Indexed: 06/03/2023]
Abstract
This work assesses the influence of the operating conditions H2O2 dose (20 or 100% of the stoichiometric amount), temperature (20 or 70°C), and the presence of chloride in the oxidation medium in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during Fenton treatment of aqueous samples of 2-chlorophenol, 2-CP, one of the strongest precursor of PCDD/Fs. After 4h of oxidation in the experiments carried out with 20% H2O2 chlorinated phenoxyphenols and biphenyls, which are intermediates in PCDD/Fs formation, as well as PCDD/Fs were observed, resulting in concentrations 11 times higher than in the untreated sample. Additionally, when NaCl was also present in the reaction medium, PCDD/Fs were formed at higher extent, with a total concentration 74.4 times higher than in the untreated 2-CP solution. Results depicted a preferential formation of PCDFs over PCDDs, with dominance of lower chlorinated PCDD/Fs (tetra and penta-PCDD/Fs). Besides, the formation of the most toxic PCDD/Fs congeners (2,3,7,8-PCDD/Fs) was not favored under the operating conditions used in this work.
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Affiliation(s)
- Marta Vallejo
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - M Fresnedo San Román
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
| | - Inmaculada Ortiz
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain.
| | - Angel Irabien
- Departamento de Ingenierías Química y Biomolecular, ETSIIyT, Universidad de Cantabria, Avda. de los Castros, 39005 Santander, Spain
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