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Fernández-Marchante CM, Vieira Dos Santos E, Souza FL, Martínez-Huitle CA, Rodríguez-Gómez A, Lobato J, Rodrigo MA. Environmental impact assessment of the electrokinetic adsorption barriers to remove different herbicides from agricultural soils. Sci Total Environ 2024; 927:172287. [PMID: 38593877 DOI: 10.1016/j.scitotenv.2024.172287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 03/15/2024] [Accepted: 04/05/2024] [Indexed: 04/11/2024]
Abstract
In this study, the sustainability of the electrokinetic remediation soil flushing (EKSFs) process integrated without and with adsorption barriers (EKABs) have been evaluated for the treatment of four soils contaminated with Atrazine, Oxyfluorfen, Chlorosulfuron and 2,4-D. To this purpose, the environmental effects of both procedures (EKSFs and EKABs) have been determined through a life cycle assessment (LCA). SimaPro 9.3.0.3 was used as software tool and Ecoinvent 3.3 as data base to carry out the inventory of the equipment of each remediation setup based on experimental measurements. The environmental burden was quantified using the AWARE, USEtox, IPPC, and ReCiPe methods into 3 Endpoint impact categories (and damage to human health, ecosystem and resources) and 7 Midpoints impact categories (water footprint, global warming potential, ozone depletion, human toxicity (cancer and human non-cancer), freshwater ecotoxicity and terrestrial ecotoxicity). In general terms, the energy applied to treatment (using the Spanish energy mix) was the parameter with the greatest influence on the carbon footprint, ozone layer depletion and water footprint accounting for around 70 % of the overall impact contribution. On the other hand, from the point of view of human toxicity and freshwater ecotoxicity of soil treatments with 32 mg kg-1 of the different pesticides, the EKSF treatment is recommended for soils with Chlorosulfuron. In this case, the carbon footprint and water footprint reached values around 0.36 kg of CO2 and 114 L of water per kg of dry soil, respectively. Finally, a sensitivity analysis was performed assuming different scenarios.
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Affiliation(s)
- C M Fernández-Marchante
- Department of Chemical Engineering, Universidad de Castilla-La Mancha, Campus Universitario s/n, Ciudad Real 13071, Spain.
| | - E Vieira Dos Santos
- Renewable Energies and Environmental Sustainability Research Group, Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitário, Av. Salgado Filho 3000, Lagoa Nova, CEP 59078-970 Natal, Rio Grande do Norte, Brazil
| | - F L Souza
- São Carlos Institute of Chemistry, University of São Paulo (USP), Trabalhador São-carlense street 400, SP, São Carlos 13566-590, Brazil
| | - C A Martínez-Huitle
- Renewable Energies and Environmental Sustainability Research Group, Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitário, Av. Salgado Filho 3000, Lagoa Nova, CEP 59078-970 Natal, Rio Grande do Norte, Brazil
| | - A Rodríguez-Gómez
- Department of Chemical Engineering, Universidad de Castilla-La Mancha, Campus Universitario s/n, Ciudad Real 13071, Spain
| | - J Lobato
- Department of Chemical Engineering, Universidad de Castilla-La Mancha, Campus Universitario s/n, Ciudad Real 13071, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, Universidad de Castilla-La Mancha, Campus Universitario s/n, Ciudad Real 13071, Spain
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Kanabata BT, Souza FL, Biz G, Pescim RR, Soares AL. Relationship Between Pre-Slaughter Factors and Major Causes of Carcass Condemnation in a Broiler Slaughterhouse under Federal Inspection. Braz J Poult Sci 2023. [DOI: 10.1590/1806-9061-2022-1669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - FL Souza
- State University of Londrina, Brazil
| | - G Biz
- State University of Londrina, Brazil
| | - RR Pescim
- State University of Londrina, Brazil
| | - AL Soares
- State University of Londrina, Brazil
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3
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Fernández-Marchante CM, Souza FL, Millán M, Lobato J, Rodrigo MA. Can the green energies improve the sustainability of electrochemically-assisted soil remediation processes? Sci Total Environ 2022; 803:149991. [PMID: 34482137 DOI: 10.1016/j.scitotenv.2021.149991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/30/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
The green powering of electrochemically-assisted soil remediation processes had been strongly discouraged. Low remediation efficiencies have been reported as a consequence of the reversibility of the transport processes when no power is applied to the electrodes, due to the intermittent powering of renewable sources. However, it has been missed a deeper evaluation from the environmental point of view. This work goes further and seeks to quantify, using life cycle assessment tools, the environmental impacts related to the electro-kinetic treatments powered by different sources: grid (Spanish energy mix), photovoltaic and wind sources. The global warming potential and the ozone depletion showed higher environmental impacts in case of using green energies, associated with the manufacturing of the energy production devices. In contrast to that, results pointed out the lowest water consumption for the treatment powered with solar panels. The huge water requirements to produce energy, considering a Spanish energy mix, drop the sustainability of this powering strategy in terms of water footprint. Regarding toxicities, the pollutant toxicity was highly got rid of after 15 days of treatment, regardless the powering source used. Nevertheless, the manufacturing of energy and green energy production devices has a huge impact into the toxicity of the remediation treatments, increasing massively the total toxicity of the process, being this effect less prominent by the electro-kinetic treatment solar powered. In view of the overall environmental impact assessed, according to mid and endpoint impact categories, it can be claimed that, despite the high energy requirements and affectation to the global warming potential, the use of solar power is a more sustainable alternative to remediate polluted soils by electrochemical techniques.
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Affiliation(s)
- C M Fernández-Marchante
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
| | - F L Souza
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M Millán
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - J Lobato
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
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4
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Escalona-Durán F, Muñoz-Morales M, Souza FL, Sáez C, Cañizares P, Martínez-Huitle CA, Rodrigo MA. Cobalt mediated electro-scrubbers for the degradation of gaseous perchloroethylene. Chemosphere 2021; 279:130525. [PMID: 33866102 DOI: 10.1016/j.chemosphere.2021.130525] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/03/2021] [Accepted: 04/05/2021] [Indexed: 06/12/2023]
Abstract
This work focuses on the treatment of gaseous perchloroethylene (PCE) using electro-scrubbing with diamond electrodes and cobalt mediators. PCE was obtained by direct desorption from an aqueous solution containing 150 mg L-1, trying to a real pollution case. The electro-scrubber consisted of a packed absorption column connected with an undivided electrochemical cell. Diamond anodes supported on two different substrates (tantalum and silicon) were used and the results indicated that Ta/BDD was more successful in the production of Co (III) species and in the degradation of PCE. Three experimental systems were studied for comparison purposes: absorbent free of Co (III) precursors, absorbent containing Co (III) precursors, and absorbent containing Co (III) precursors undergoing previous electrolysis to the electro-scrubbing to facilitate the accumulation of oxidants. The most successful option was the last, confirming the important role of mediated electrochemical processes in the degradation of PCE. Trichloroacetic acid (TCA) and carbon tetrachloride (CCl4) were found as the primary reaction products and ethyl chloroacetate esters were also identified. A comprehensive mechanism of the processes happening inside electro-scrubber is proposed.
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Affiliation(s)
- F Escalona-Durán
- Institute of Chemistry, Environmental and Applied Electrochemical Laboratory, Federal University of Rio Grande Do Norte, Lagoa Nova, CEP 59078-970, Natal, RN, Brazil
| | - M Muñoz-Morales
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla La Mancha, Campus Universitario S/n, 13071, Ciudad Real, Spain
| | - F L Souza
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla La Mancha, Campus Universitario S/n, 13071, Ciudad Real, Spain
| | - C Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla La Mancha, Campus Universitario S/n, 13071, Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla La Mancha, Campus Universitario S/n, 13071, Ciudad Real, Spain
| | - C A Martínez-Huitle
- Institute of Chemistry, Environmental and Applied Electrochemical Laboratory, Federal University of Rio Grande Do Norte, Lagoa Nova, CEP 59078-970, Natal, RN, Brazil
| | - M A Rodrigo
- Department of Chemical Engineering, Faculty of Chemical Sciences & Technologies, University of Castilla La Mancha, Campus Universitario S/n, 13071, Ciudad Real, Spain.
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5
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Fernández-Marchante CM, Souza FL, Millán M, Lobato J, Rodrigo MA. Does intensification with UV light and US improve the sustainability of electrolytic waste treatment processes? J Environ Manage 2021; 279:111597. [PMID: 33168294 DOI: 10.1016/j.jenvman.2020.111597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/29/2020] [Accepted: 10/30/2020] [Indexed: 05/03/2023]
Abstract
This work aims to assess the influence of ultrasounds (US) application or ultraviolet (UV) light irradiation on the efficiency and sustainability of the treatment of wastes by conductive diamond electrochemical oxidation (CDEO). To do this, a life cycle assessment (LCA) is carried out in order to quantify the environmental impacts of the intensified CDEO processes. Inventories of three bench scale remediation plants (CDEO, Sono-CDEO and Photo-CDEO) in which the different technologies are implemented are performed by means of Ecoinvent 3.3 data base. AWARE, USEtox, IPPC and ReCiPe methodologies are used to quantify the environmental burden into 5 midpoint (water footprint, global warming 100a, ozone layer depletion, human toxicity, freshwater ecotoxicity) and 17 endpoint impact categories. Photo-CDEO attains the faster and more efficient removal in terms of energy consumed. All impact categories are lower in the case in which UV light irradiation is coupled to the CDEO treatment, particularly if the electrolyte does not contain chloride anions. From the point of view of toxicity and ecotoxicity, it is essential to achieve a complete mineralization, because of the intermediates generated into wastes containing chloride anions can become more hazardous than the initial pesticide. The operation of these technologies at large current densities shows positive results from the sustainability point of view, despite the huge environmental impact related to the energy production. Data notice that almost a 99.0% of the total global warming potential is mainly due to the electricity required during the electrochemical treatment, being higher by the sono and photo CDEO treatments because of the use of additional devices. Nevertheless, this issue can be overcome by means of using renewable energies as power sources of these remediation treatments. According to results, it can be claimed that the electrochemical technologies may successfully compete with other AOPs in terms of sustainability.
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Affiliation(s)
- C M Fernández-Marchante
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071, Ciudad Real, Spain.
| | - F L Souza
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071, Ciudad Real, Spain
| | - M Millán
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071, Ciudad Real, Spain
| | - J Lobato
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071, Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071, Ciudad Real, Spain
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6
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Fernández-Marchante CM, Souza FL, Millán M, Lobato J, Rodrigo MA. Improving sustainability of electrolytic wastewater treatment processes by green powering. Sci Total Environ 2021; 754:142230. [PMID: 33254883 DOI: 10.1016/j.scitotenv.2020.142230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/18/2020] [Accepted: 09/03/2020] [Indexed: 05/03/2023]
Abstract
This work focuses on the evaluation of the impact of powering electrolytic wastewater treatment processes with grid or renewable energy on the sustainability of this electrochemical remediation technology. To face this goal, it was performed an inventory of three bench-scale plants made up by the same treatment technology but powered from different supplies: connected to grid and directly coupled with solar photovoltaic panels or a wind turbine. Results show that the powering mode can significantly affect the environmental risks of the treatment, not only in terms of electricity demand but also on the formation of intermediates, which are more important in the cases in which the intensity profile varied. A life cycle assessment (LCA) is carried out in order to quantify the environmental impacts of green powering electrolytic wastewater treatment processes. Ecoinvent 3.3 data base, AWARE, USEtox, IPPC and ReCiPe methodologies are used to quantify the environmental burden into 5 midpoint (water footprint, global warming 100a, ozone layer depletion, human toxicity, freshwater ecotoxicity) and 17 endpoint impact categories. All impact categories are higher in the case in which the supplied power cames from a electricity grid mix. For the removal of 0.1 g 2,4-dichlorophenoxyacetic acid (2,4D) per liter (functional unit) of treated wastewater releases 0.14 kg CO2 eq. If the energy is provided by a wind turbine or a solar panel the processes emit 0.020 kg CO2 eq and 0.019 kg CO2 eq, respectively. A comparison of the impact based on the grid mix used in different countries is also made, which has pointed out the relevance of this input on the sustainability of the environmental electrochemical technologies.
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Affiliation(s)
- C M Fernández-Marchante
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071 Ciudad Real, Spain.
| | - F L Souza
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071 Ciudad Real, Spain
| | - M Millán
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071 Ciudad Real, Spain
| | - J Lobato
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071 Ciudad Real, Spain
| | - M A Rodrigo
- Department of Chemical Engineering, University of Castilla La Mancha, Campus Universitario s/n. 13071 Ciudad Real, Spain
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7
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Barbosa Ferreira M, Souza FL, Muñoz-Morales M, Sáez C, Cañizares P, Martínez-Huitle CA, Rodrigo MA. Clopyralid degradation by AOPs enhanced with zero valent iron. J Hazard Mater 2020; 392:122282. [PMID: 32105951 DOI: 10.1016/j.jhazmat.2020.122282] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/22/2020] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
Four different technologies have been compared (photolysis, ZVI + photolysis, electrolysis and ZVI + electrolysis) regarding the: (1) degradation of clopyralid, (2) extent of its mineralization, (3) formation of by-products and main reaction pathways. Results show that photolysis is the less efficient treatment and it only attains 5 % removal of the pollutant, much less than ZVI, which reaches 45 % removal and that electrolysis, which attains complete removal and 78 % mineralization within 4 h. When ZVI is used as pre-treatment of electrolysis, it was obtained the most efficient technology. The identification of transformation products was carried out for each treatment by LCMS. In total, ten products were identified. Tentative pathways for preferential clopyralid degradation for all processes were proposed. This work draws attention of the synergisms caused by the coupling of techniques involving the treatment of chlorinated compound and sheds light on how the preferential mechanisms of each treatment evaluated occurred.
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Affiliation(s)
- M Barbosa Ferreira
- Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitario 3000, 59078-970 Natal, RN, Brazil
| | - F L Souza
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - M Muñoz-Morales
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - P Cañizares
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain
| | - C A Martínez-Huitle
- Institute of Chemistry, Federal University of Rio Grande do Norte, Campus Universitario 3000, 59078-970 Natal, RN, Brazil
| | - M A Rodrigo
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
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Souza FL, Llanos J, Sáez C, Lanza MRV, Rodrigo MA, Cañizares P. Performance of wind-powered soil electroremediation process for the removal of 2,4-D from soil. J Environ Manage 2016; 171:128-132. [PMID: 26861224 DOI: 10.1016/j.jenvman.2016.01.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/19/2015] [Accepted: 01/28/2016] [Indexed: 06/05/2023]
Abstract
In this work, it is studied a wind-powered electrokinetic soil flushing process for the removal of pesticides from soil. This approach aims to develop an eco-friendly electrochemical soil treatment technique and to face the in-situ treatment of polluted soils at remote locations. Herbicide 2,4 dichlorophenoxyacetic acid (2,4-D) is selected as a model pollutant for the soil treatment tests. The performance of the wind-powered process throughout a 15 days experiment is compared to the same remediation process powered by a conventional DC power supply. The wind-powered test covered many different wind conditions (from calm to near gale), being performed 20.7% under calm conditions and 17% under moderate or gentle breeze. According to the results obtained, the wind-powered soil treatment is feasible, obtaining a 53.9% removal of 2,4-D after 15 days treatment. Nevertheless, the remediation is more efficient if it is fed by a constant electric input (conventional DC power supply), reaching a 90.2% removal of 2,4-D with a much lower amount of charge supplied (49.2 A h kg(-1) and 4.33 A h kg(-1) for wind-powered and conventional) within the same operation time.
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Affiliation(s)
- F L Souza
- Institute of Chemistry of São Carlos, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - J Llanos
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain.
| | - C Sáez
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
| | - M R V Lanza
- Institute of Chemistry of São Carlos, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - M A Rodrigo
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
| | - P Cañizares
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
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Souza FL, Lanza MRV, Llanos J, Sáez C, Rodrigo MA, Cañizares P. A wind-powered BDD electrochemical oxidation process for the removal of herbicides. J Environ Manage 2015; 158:36-39. [PMID: 25950835 DOI: 10.1016/j.jenvman.2015.04.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 04/14/2015] [Accepted: 04/25/2015] [Indexed: 06/04/2023]
Abstract
In the search for greener treatment technologies, this work studies the coupling of a wind turbine energy supply with an electrolytic cell (CWTEC device) for the remediation of wastewater polluted with pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). The discontinuous and unforeseeable supply of energy is the main challenge inspiring this new proposal, which aims at reducing the environmental impact of electrolytic treatment by using a green energy supply. The results obtained using the coupled technologies are compared with those obtained by powering the electrolyser with a traditional power supply with a similar current intensity. The mineralisation of wastewater can be accomplished independently of how the electrolytic cell is powered, although differences in performance are clearly observed in the total organic carbon (TOC) and 2,4-D decays. These changes can be explained in terms of the changing profile of the current intensity, which influences the concentrations of the oxidants produced and thereby the mediated electrolytic process.
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Affiliation(s)
- F L Souza
- Institute of Chemistry of São Carlos, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - M R V Lanza
- Institute of Chemistry of São Carlos, University of São Paulo, P.O. Box 780, 13560-970 São Carlos, SP, Brazil
| | - J Llanos
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain.
| | - C Sáez
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
| | - M A Rodrigo
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
| | - P Cañizares
- Chemical Engineering Department, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
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Souza FL, Teodoro TQ, Vasconcelos VM, Migliorini FL, Lima Gomes PCF, Ferreira NG, Baldan MR, Haiduke RLA, Lanza MRV. Electrochemical oxidation of imazapyr with BDD electrode in titanium substrate. Chemosphere 2014; 117:596-603. [PMID: 25461923 DOI: 10.1016/j.chemosphere.2014.09.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/11/2014] [Accepted: 09/15/2014] [Indexed: 06/04/2023]
Abstract
In this work we have studied the treatment of imazapyr by electrochemical oxidation with boron-doped diamond anode. Electrochemical degradation experiments were performed in a one-compartment cell containing 0.45 L of commercial formulations of herbicide in the pH range 3.0-10.0 by applying a density current between 10 and 150 mA cm(-2) and in the temperature range 25-45 °C. The maximum current efficiencies were obtained at lower current densities since the electrochemical system is under mass transfer control. The mineralization rate increased in acid medium and at higher temperatures. The treatment was able to completely degrade imazapyr in the range 4.6-100.0 mg L(-1), although the current charge required rises along with the increasing initial concentration of the herbicide. Toxicity analysis with the bioluminescent bacterium Vibrio fischeri showed that at higher pollutant concentrations the toxicity was reduced after the electrochemical treatment. To clarify the reaction pathway for imazapyr mineralization by OH radicals, LC-MS/MS analyses we performed together with a theoretical study. Ions analysis showed the formation of high levels of ammonium in the cathode. The main final products of the electrochemical oxidation of imazapyr with diamond thin film electrodes are formic, acetic and butyric acids.
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Affiliation(s)
- F L Souza
- Instituto de Química de São Carlos, Universidade de São Paulo, P.O. Box 780, São Carlos, SP, Brazil
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Correia SL, Souza FL, Dienstmann G, Segadães AM. Assessment of the recycling potential of fresh concrete waste using a factorial design of experiments. Waste Manag 2009; 29:2886-2891. [PMID: 19596189 DOI: 10.1016/j.wasman.2009.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 02/18/2009] [Accepted: 06/11/2009] [Indexed: 05/28/2023]
Abstract
Recycling of industrial wastes and by-products can help reduce the cost of waste treatment prior to disposal and eventually preserve natural resources and energy. To assess the recycling potential of a given waste, it is important to select a tool capable of giving clear indications either way, with the least time and work consumption, as is the case of modelling the system properties using the results obtained from statistical design of experiments. In this work, the aggregate reclaimed from the mud that results from washout and cleaning operations of fresh concrete mixer trucks (fresh concrete waste, FCW) was recycled into new concrete with various water/cement ratios, as replacement of natural fine aggregates. A 3(2) factorial design of experiments was used to model fresh concrete consistency index and hardened concrete water absorption and 7- and 28-day compressive strength, as functions of FCW content and water/cement ratio, and the resulting regression equations and contour plots were validated with confirmation experiments. The results showed that the fresh concrete workability worsened with the increase in FCW content but the water absorption (5-10 wt.%), 7-day compressive strength (26-36 MPa) and 28-day compressive strength (32-44 MPa) remained within the specified ranges, thus demonstrating that the aggregate reclaimed from FCW can be recycled into new concrete mixtures with lower natural aggregate content.
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Affiliation(s)
- S L Correia
- State University of Santa Catarina, Centre of Technology Sciences (UDESC/CCT), 89223-100 Joinville-SC, Brazil
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