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Tayar Galante M, Živković A, Alvim J, Calchi Kleiner CC, Sangali M, Taylor SFR, Greer AJ, Hardacre C, Rajeshwar K, Caram R, Bertazzoli R, Macaluso RT, de Leeuw NH, Longo C. Arc Synthesis, Crystal Structure, and Photoelectrochemistry of Copper(I) Tungstate. ACS Appl Mater Interfaces 2021; 13:32865-32875. [PMID: 34251184 PMCID: PMC8311641 DOI: 10.1021/acsami.1c03928] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
A little-studied p-type ternary oxide semiconductor, copper(I) tungstate (Cu2WO4), was assessed by a combined theoretical/experimental approach. A detailed computational study was performed to solve the long-standing debate on the space group of Cu2WO4, which was determined to be triclinic P1. Cu2WO4 was synthesized by a time-efficient, arc-melting method, and the crystalline reddish particulate product showed broad-band absorption in the UV-visible spectral region, thermal stability up to ∼260 °C, and cathodic photoelectrochemical activity. Controlled thermal oxidation of copper from the Cu(I) to Cu(II) oxidation state showed that the crystal lattice could accommodate Cu2+ cations up to ∼260 °C, beyond which the compound was converted to CuO and CuWO4. This process was monitored by powder X-ray diffraction and X-ray photoelectron spectroscopy. The electronic band structure of Cu2WO4 was contrasted with that of the Cu(II) counterpart, CuWO4 using spin-polarized density functional theory (DFT). Finally, the compound Cu2WO4 was determined to have a high-lying (negative potential) conduction band edge underlining its promise for driving energetic photoredox reactions.
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Affiliation(s)
- Miguel Tayar Galante
- Institute
of Chemistry, University of Campinas—UNICAMP, 13083-970 Campinas, Brazil
- Center
for Innovation on New Energies, University
of Campinas, CEP 13083-841 Campinas, Brazil
| | - Aleksandar Živković
- Department
of Earth Sciences, Utrecht University, Princetonlaan 8a, 3548CB Utrecht, The Netherlands
| | - Jéssica
Costa Alvim
- Institute
of Chemistry, University of Campinas—UNICAMP, 13083-970 Campinas, Brazil
- Center
for Innovation on New Energies, University
of Campinas, CEP 13083-841 Campinas, Brazil
| | | | - Márcio Sangali
- Faculty
of Mechanical Engineering, University of
Campinas—UNICAMP, 13083-970 Campinas, Brazil
| | - S. F. Rebecca Taylor
- Department
of Chemical Engineering and Analytical Science, University of Manchester, The Mill, Sackville Street, Manchester M13 9PL, United Kingdom
| | - Adam J. Greer
- Department
of Chemical Engineering and Analytical Science, University of Manchester, The Mill, Sackville Street, Manchester M13 9PL, United Kingdom
| | - Christopher Hardacre
- Department
of Chemical Engineering and Analytical Science, University of Manchester, The Mill, Sackville Street, Manchester M13 9PL, United Kingdom
| | - Krishnan Rajeshwar
- Department
of Chemistry and Biochemistry, The University
of Texas at Arlington, Arlington, Texas 76019, United States
| | - Rubens Caram
- Faculty
of Mechanical Engineering, University of
Campinas—UNICAMP, 13083-970 Campinas, Brazil
| | - Rodnei Bertazzoli
- Faculty
of Mechanical Engineering, University of
Campinas—UNICAMP, 13083-970 Campinas, Brazil
| | - Robin T. Macaluso
- Department
of Chemistry and Biochemistry, The University
of Texas at Arlington, Arlington, Texas 76019, United States
| | - Nora H. de Leeuw
- Department
of Earth Sciences, Utrecht University, Princetonlaan 8a, 3548CB Utrecht, The Netherlands
- School
of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, United
Kingdom
| | - Claudia Longo
- Institute
of Chemistry, University of Campinas—UNICAMP, 13083-970 Campinas, Brazil
- Center
for Innovation on New Energies, University
of Campinas, CEP 13083-841 Campinas, Brazil
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Cordeiro-Junior PJM, Kronka MS, Goulart LA, Veríssimo NC, Mascaro LH, Santos MCD, Bertazzoli R, Lanza MRDV. Catalysis of oxygen reduction reaction for H2O2 electrogeneration: The impact of different conductive carbon matrices and their physicochemical properties. J Catal 2020. [DOI: 10.1016/j.jcat.2020.09.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Rocha R, Beati A, Valim R, Steter J, Bertazzoli R, Lanza MV. AVALIAÇÃO DOS SUBPRODUTOS DE DEGRADAÇÃO DO HERBICIDA AMETRINA OBTIDOS VIA PROCESSOS OXIDATIVOS AVANÇADOS. Revista Brasileira de Engenharia de Biossistemas 2018. [DOI: 10.18011/bioeng2018v12n1p52-67] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
As tecnologias alternativas, como os processos oxidativos avançados (POA), contribuem para o controle das poluições ambientais e nesse contexto uma das informações mais importantes é a determinação dos subprodutos de degradação formados em cada condição de estudo. Nesse trabalho foram avaliadas diferentes concentrações de H2O2, pH e temperatura, sempre com o objetivo de promover a quebra da molécula do herbicida triazínico ametrina e avaliar os principais subprodutos formados no processo de degradação. O maior número de subprodutos foi identificado utilizando a espectrometria de massas com inserção direta nas condições com 20% e 25% de H2O2 a 65 ºC, sendo detectados 5 possíveis compostos originados a partir da fragmentação da molécula original da ametrina.
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Affiliation(s)
- R.S. Rocha
- USP - Universidade de São Paulo, Departamento de Ciências Básicas e Ambientais, Escola de Engenharia de Lorena, Lorena, SP, Brasil
| | - A.A.G.F. Beati
- USF - Universidade São Francisco, Grupo de Pesquisas em Meio Ambiente e Sustentabilidade, Itatiba, SP, Brasil
| | - R.B. Valim
- USP - Universidade de São Paulo, Departamento de Ciências Básicas e Ambientais, Escola de Engenharia de Lorena, Lorena, SP, Brasil
| | - J.R. Steter
- USP - Universidade de São Paulo, Departamento de Química e Física Molecular, Instituto de Química de São Carlos, São Carlos, SP, Brasil
| | - R. Bertazzoli
- UNICAMP - Universidade Estadual de Campinas, Departamento de Engenharia de Materiais, Faculdade de Engenharia Mecânica, Campinas, SP, Brasil
| | - M.R. V. Lanza
- USP - Universidade de São Paulo, Departamento de Química e Física Molecular, Instituto de Química de São Carlos, São Carlos, SP, Brasil
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Oliveira HG, Ferreira LH, Bertazzoli R, Longo C. Remediation of 17-α-ethinylestradiol aqueous solution by photocatalysis and electrochemically-assisted photocatalysis using TiO2 and TiO2/WO3 electrodes irradiated by a solar simulator. Water Res 2015; 72:305-14. [PMID: 25238917 DOI: 10.1016/j.watres.2014.08.042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [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: 06/03/2014] [Revised: 08/17/2014] [Accepted: 08/26/2014] [Indexed: 05/24/2023]
Abstract
TiO2 and TiO2/WO3 electrodes, irradiated by a solar simulator in configurations for heterogeneous photocatalysis (HP) and electrochemically-assisted HP (EHP), were used to remediate aqueous solutions containing 10 mg L(-1) (34 μmol L(-1)) of 17-α-ethinylestradiol (EE2), active component of most oral contraceptives. The photocatalysts consisted of 4.5 μm thick porous films of TiO2 and TiO2/WO3 (molar ratio W/Ti of 12%) deposited on transparent electrodes from aqueous suspensions of TiO2 particles and WO3 precursors, followed by thermal treatment at 450 (°)C. First, an energy diagram was organized with photoelectrochemical and UV-Vis absorption spectroscopy data and revealed that EE2 could be directly oxidized by the photogenerated holes at the semiconductor surfaces, considering the relative HOMO level for EE2 and the semiconductor valence band edges. Also, for the irradiated hybrid photocatalyst, electrons in TiO2 should be transferred to WO3 conduction band, while holes move toward TiO2 valence band, improving charge separation. The remediated EE2 solutions were analyzed by fluorescence, HPLC and total organic carbon measurements. As expected from the energy diagram, both photocatalysts promoted the EE2 oxidation in HP configuration; after 4 h, the EE2 concentration decayed to 6.2 mg L(-1) (35% of EE2 removal) with irradiated TiO2 while TiO2/WO3 electrode resulted in 45% EE2 removal. A higher performance was achieved in EHP systems, when a Pt wire was introduced as a counter-electrode and the photoelectrodes were biased at +0.7 V; then, the EE2 removal corresponded to 48 and 54% for the TiO2 and TiO2/WO3, respectively. The hybrid TiO2/WO3, when compared to TiO2 electrode, exhibited enhanced sunlight harvesting and improved separation of photogenerated charge carriers, resulting in higher performance for removing this contaminant of emerging concern from aqueous solution.
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Affiliation(s)
- Haroldo G Oliveira
- Institute of Chemistry, University of Campinas - UNICAMP, PO Box 6154, 13083-970 Campinas, SP, Brazil
| | - Leticia H Ferreira
- Faculty of Mechanical Engineering, University of Campinas - UNICAMP, PO Box 6122, 13083-970 Campinas, SP, Brazil
| | - Rodnei Bertazzoli
- Faculty of Mechanical Engineering, University of Campinas - UNICAMP, PO Box 6122, 13083-970 Campinas, SP, Brazil
| | - Claudia Longo
- Institute of Chemistry, University of Campinas - UNICAMP, PO Box 6154, 13083-970 Campinas, SP, Brazil.
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Barros WRP, Borges MP, Reis RM, Rocha RS, Bertazzoli R, Lanza MRV. Degradation of Dipyrone by the Electro-Fenton Process in an Electrochemical Flow Reactor with a Modified Gas Diffusion Electrode. J BRAZIL CHEM SOC 2014. [DOI: 10.5935/0103-5053.20140160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Codolo M, Bizzo W, Bertazzoli R. Performance of a UV-assisted Hydrogen-peroxide-fed Spray Tower for Sulfur Dioxide Abatement. Chem Eng Technol 2013. [DOI: 10.1002/ceat.201200699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Affiliation(s)
- Raul S. Figueiredo
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Rua Mendeleyev 200,
13083-860, Campinas, São Paulo, Brazil
| | - Rodnei Bertazzoli
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Rua Mendeleyev 200,
13083-860, Campinas, São Paulo, Brazil
| | - Christiane A. Rodrigues
- Instituto de Ciências
Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Rua São Nicolau
210, 09913-030, Diadema, São Paulo, Brazil
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Rocha RS, Reis RM, Lanza MR, Bertazzoli R. Electrosynthesis of methanol from methane: The role of V2O5 in the reaction selectivity for methanol of a TiO2/RuO2/V2O5 gas diffusion electrode. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2012.09.113] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rocha RS, Reis RM, Beati AAGF, Lanza MRV, Sotomayor MDPT, Bertazzoli R. Desenvolvimento e avaliação de eletrodos de difusão gasosa (EDG) para geração de H2O2 in situ e sua aplicação na degradação do corante reativo azul 19. QUIM NOVA 2012. [DOI: 10.1590/s0100-40422012001000014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Reis RM, Beati AAGF, Rocha RS, Assumpção MHMT, Santos MC, Bertazzoli R, Lanza MRV. Use of Gas Diffusion Electrode for the In Situ Generation of Hydrogen Peroxide in an Electrochemical Flow-By Reactor. Ind Eng Chem Res 2011. [DOI: 10.1021/ie201317u] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rafael M. Reis
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970, São Carlos, SP, Brazil
| | - André A. G. F. Beati
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970, São Carlos, SP, Brazil
| | - Robson S. Rocha
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970, São Carlos, SP, Brazil
| | - Mônica H. M. T. Assumpção
- Laboratório de Eletroquímica e Materiais Nanoestruturados, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia 166, Bairro Bangu, 09210-170, Santo André, SP, Brazil
| | - Mauro C. Santos
- Laboratório de Eletroquímica e Materiais Nanoestruturados, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia 166, Bairro Bangu, 09210-170, Santo André, SP, Brazil
| | - Rodnei Bertazzoli
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, 13083-970, Campinas, SP, Brazil
| | - Marcos R. V. Lanza
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970, São Carlos, SP, Brazil
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Rocha RS, Lanza MRV, Bertazzoli R. Electrosynthesis of Ethylene Glycol from Oxidation of Ethylene Using a TiO2–RuO2/PTFE Gas Diffusion Electrode. Electrocatalysis (N Y) 2011. [DOI: 10.1007/s12678-011-0063-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Sousa MFB, Sanchez EMS, Bertazzoli R. Scanning electrochemical microscopy: study of the deposition and stripping mechanism of lead in the presence of copper. J BRAZIL CHEM SOC 2011. [DOI: 10.1590/s0103-50532011000600012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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13
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Oliveira PCAD, Bertazzoli R. Determinação da densidade de corrente de corrosão em meios de baixa condutividade: uso de microeletrodos para minimizar a queda ôhmica. QUIM NOVA 2011. [DOI: 10.1590/s0100-40422011000200027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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14
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Rocha RS, Camargo LM, Lanza MRV, Bertazzoli R. A Feasibility Study of the Electro-recycling of Greenhouse Gases: Design and Characterization of a (TiO2/RuO2)/PTFE Gas Diffusion Electrode for the Electrosynthesis of Methanol from Methane. Electrocatalysis (N Y) 2010. [DOI: 10.1007/s12678-010-0029-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Forti JC, Ribeiro J, Lanza MRV, de Andrade AR, Bertazzoli R. Electrochemical Characterization of DSA®-Type Electrodes Using Niobium Substrate. Electrocatalysis (N Y) 2010. [DOI: 10.1007/s12678-010-0020-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Barbosa CP, Malpass GRP, Miwa DW, Gomes L, Bertazzoli R, Motheo AJ. Electrochemical removal of CuII in the presence of humic acid. J BRAZIL CHEM SOC 2010. [DOI: 10.1590/s0103-50532010000400010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Malpass GRP, Miwa DW, Gomes L, Azevedo EB, Vilela WFD, Fukunaga MT, Guimarães JR, Bertazzoli R, Machado SAS, Motheo AJ. Photo-assisted electrochemical degradation of the commercial herbicide atrazine. Water Sci Technol 2010; 62:2729-36. [PMID: 21123900 DOI: 10.2166/wst.2010.207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This paper presents a degradation study of the pesticide atrazine using photo-assisted electrochemical methods at a dimensionally stable anode (DSA(®)) of nominal composition Ti/Ru(0.3)Ti(0.7)O(2) in a prototype reactor. The effects of current density, electrolyte flow-rate, as well as the use of different atrazine concentrations are reported. The results indicate that the energy consumption is substantially reduced for the combined photochemical and electrochemical processes when compared to the isolated systems. It is observed that complete atrazine removal is achieved at low current densities when using the combined method, thus reducing the energy required to operate the electrochemical system. The results also include the investigation of the phytotoxicity of the treated solutions.
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Affiliation(s)
- G R P Malpass
- Universidade Federal do ABC, Rua Santa Adélia, Santo André SP 09.210-170, Brazil.
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Forti JC, Venâncio CE, Lanza MRV, Bertazzoli R. Effects of the modification of gas diffusion electrodes by organic redox catalysts for hydrogen peroxide electrosynthesis. J BRAZIL CHEM SOC 2008. [DOI: 10.1590/s0103-50532008000400006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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de Oliveira B, Bertazzoli R. On the role of the surfactant aliquat® 336 on the kinetics of oxygen reduction reaction and on the rate of hydrogen peroxide electrosynthesis. J Electroanal Chem (Lausanne) 2007. [DOI: 10.1016/j.jelechem.2007.08.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Moraes PB, Pelegrino RRL, Bertazzoli R. Degradation of acid blue 40 dye solution and dye house wastewater from textile industry by photo-assisted electrochemical process. J Environ Sci Health A Tox Hazard Subst Environ Eng 2007; 42:2131-2138. [PMID: 18074285 DOI: 10.1080/10934520701629591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In this paper, electrochemical and photo-assisted electrochemical processes are used for color, total organic carbon (TOC) and chemical oxygen demand (COD) degradation of one of the most abundant and strongly colored industrial wastewaters, which results from the dyeing of fibers and fabrics in the textile industry. The experiments were carried out in an 18 L pilot-scale tubular flow reactor with 70%TiO(2)/30%RuO(2) DSA. A synthetic acid blue 40 solution and real dye house wastewater, containing the same dye, were used for the experiments. By using current density of 80 mA cm(-2) electrochemical process has the capability to remove 80% of color, 46% of TOC and 69% of COD. When used the photochemical process with 4.6 mW cm(-2) of 254 nm UV-C radiation to assist the electrolysis, has been obtained 90% of color, 64% of TOC and 60% of COD removal in 90 minutes of processing; furthermore, 70% of initial color was degraded within the first 15 minutes. Experimental runs using dye house wastewater resulted in 78% of color, 26% of TOC and 49% of COD in electrolysis at 80 mA cm(-2) and 90 min; additionally, when photo-assisted, electrolysis resulted in removals of 85% of color, 42% of TOC and 58% of COD. For the operational conditions used in this study, color, TOC and COD showed pseudo-first-order decaying profiles. Apparent rate constants for degradation of TOC and COD were improved by one order of magnitude when the photo-electrochemical process was used.
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Affiliation(s)
- Peterson B Moraes
- Department of Materials Engineering, Faculty of Mechanical Engineering, Campinas State University, Campinas, SP, Brazil.
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Badellino C, Rodrigues CA, Bertazzoli R. Oxidation of pesticides by in situ electrogenerated hydrogen peroxide: study for the degradation of 2,4-dichlorophenoxyacetic acid. J Hazard Mater 2006; 137:856-64. [PMID: 16707213 DOI: 10.1016/j.jhazmat.2006.03.035] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 03/02/2006] [Accepted: 03/03/2006] [Indexed: 05/09/2023]
Abstract
This paper reports an investigation on the performance of the H2O2 electrogeneration process on a rotating RVC cylinder cathode, and the optimization of the O2 reduction rate relative to cell potential. A study for the simultaneous oxidation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) by the in situ electrogenerated H2O2 is also reported. Experiments were performed in 0.3 M of K2SO4, pH of 10 and 3.5. Oxygen concentration in solution was kept in 25 mg L(-1). Maximum hydrogen peroxide generation rate was reached at -1.6 V versus SCE for both, acidic and alkaline solutions. Then, 100 mg L(-1) of 2,4-D was added to the solution. First order apparent rate constants for 2,4-D degradation ranged from 0.9 to 6.3x10(-5) m s(-1), depending on the catalyst used (UV or UV+Fe(II)). TOC reduction was favored in acidic medium where a decreasing of 69% of the initial concentration was observed in the process catalyzed by UV+Fe(II). This figure was an indication that some of the intermediates derived from 2,4-D decomposition remained in solution, mainly as lighter aliphatic compounds.
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Affiliation(s)
- Carla Badellino
- Faculty of Mechanical Engineering, Department of Materials Engineering, State University of Campinas, CP 6122, 13083-970 Campinas, Sao Paulo, Brazil
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Moraes PB, Bertazzoli R. Electrodegradation of landfill leachate in a flow electrochemical reactor. Chemosphere 2005; 58:41-46. [PMID: 15522331 DOI: 10.1016/j.chemosphere.2004.09.026] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 08/12/2004] [Accepted: 09/03/2004] [Indexed: 05/24/2023]
Abstract
Sanitary landfills are the major method used today for the disposal and management of municipal solid waste. Decomposition of waste and rainfall generate leachate at the bottom of landfills, causing groundwater contamination. In this study, leachate from a municipal landfill site was treated by electrochemical oxidation in a pilot scale flow reactor, using oxide-coated titanium anode. The experiments were conducted under a constant flow rate of 2000 lh(-1) and the effect of current density on chemical oxygen demand, total organic carbon, color and ammonium removal was investigated. At a current density of 116.0 mA cm(-2) and 180 min of processing, the removal rates achieved were 73% for COD, 57% for TOC, 86% for color and 49% for ammonium. The process proved effective in degrading leachate, despite this effluent's usual refractoriness to treatment.
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Affiliation(s)
- Peterson Bueno Moraes
- Faculty of Mechanical Engineering, Department of Materials Engineering, Campinas State University, C Postal 6122, 13083-970 Campinas, São Paulo, Brazil
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Pelegrino RL, Di Iglia RA, Sanches CG, Avaca LA, Bertazzoli R. Comparative Study of Commercial Oxide Electrodes Performance in Electrochemical Degradation of Organics in Aqueous Solutions. J BRAZIL CHEM SOC 2002. [DOI: 10.1590/s0103-50532002000100009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Affiliation(s)
- Marcos R. V. Lanza
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Caixa Postal 6122, 13083-970 Campinas-SP, Brazil
| | - Rodnei Bertazzoli
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Caixa Postal 6122, 13083-970 Campinas-SP, Brazil
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Pelegrini RT, Freire RS, Duran N, Bertazzoli R. Photoassisted electrochemical degradation of organic pollutants on a DSA type oxide electrode: process test for a phenol synthetic solution and its application for the E1 bleach Kraft mill effluent. Environ Sci Technol 2001; 35:2849-2853. [PMID: 11452621 DOI: 10.1021/es001784j] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this paper, the performance of a photoassisted electrolysis process, for the degradation of organic pollutants, is investigated. Results obtained in this work have shown that the thermally prepared anode of titanium, coated with 70TiO2/30RuO2, exhibits photoactivity and may be used for the treatment of effluents. A synthetic phenol aqueous solution and a real paper mill industry effluent were treated. Kinetic analysis showed a synergetic effect of electrolysis and photocatalysis and degradation rates are an order of magnitude greater than the sum of the results reached by using both processes individually. Using a 125 W mercury bulb and 20 mA cm-2, the phenol concentration decayed 85% in 90 min and 70% reduction of TOC was obtained. In the application of the treatment process for the degradation of the E1 bleach Kraft mill effluent, total phenols were practically eliminated in a short period of processing time, and color, usually resistant to biological treatment, was reduced to 10% from its initial value measured in terms of absorbance. Reductions of AOX, COD, and BOD by 25%, 30%, and 35%, respectively, were also observed.
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Affiliation(s)
- R T Pelegrini
- Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Caixa Postal 6122-13083-970, Campinas, SP, Brazil
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Rosa S, Barbosa P, Button S, Bertazzoli R. In-vitro corrosion resistance study of hot worked Ti-6Al-7Nb alloy in a isotonic medium. Braz J Chem Eng 2001. [DOI: 10.1590/s0104-66322001000100005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- S. Rosa
- Universidade Estadual de Campinas, Brasil
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Sousa MDFB, Dallan ÉJ, Bertazzoli R. Obtenção de um material adsorvente para íons de metais pesados, através da eletropolimerização de 2-mercaptobenzimidazol à superfície de carbono vítreo reticulado. QUIM NOVA 2000. [DOI: 10.1590/s0100-40422000000300009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Bertazzoli R, Rodrigues C, Dallan E, Fukunaga M, Lanza M, Leme R, Widner R. MASS TRANSPORT PROPERTIES OF A FLOW-THROUGH ELECTROLYTIC REACTOR USING A POROUS ELECTRODE: PERFORMANCE AND FIGURES OF MERIT FOR Pb(II) REMOVAL. Braz J Chem Eng 1998. [DOI: 10.1590/s0104-66321998000400008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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de Fátima Brito Sousa M, Dallan ÉJ, Yamaki SB, Bertazzoli R. Preparation of polymer-coated electrodes containing metal ions complexing sites by electropolymerization of 2-mercaptobenzimidazole and 2-mercaptobenzothiazole on glassy carbon. ELECTROANAL 1997. [DOI: 10.1002/elan.1140090807] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bertazzoli R, Widner RC, Lanza MR, Di Iglia RA, Sousa MF. Electrolytic removal of metals using a flow-through cell with a reticulated vitreous carbon cathode. J BRAZIL CHEM SOC 1997. [DOI: 10.1590/s0103-50531997000500009] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Sousa MDFB, Bertazzoli R. Preconcentration and Voltammetric Determination of Mercury(II) at a Chemically Modified Glassy Carbon Electrode. Anal Chem 1996; 68:1258-61. [DOI: 10.1021/ac950969j] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Rodnei Bertazzoli
- Departamento de Engenharia de MateriaisUNICAMP, C.P. 6122, 13083-970 Campinas, SP-Brazil
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