title: Removal of clomazone herbicide from a synthetic effluent by electrocoagulation.
abstract: The aim of this work was to investigate the kinetics of removal of clomazone herbicide from an aqueous solution by electrocoagulation. The experiments were performed in a cylindrical batch reactor with six aluminum electrodes in monopolar mode, arranged in series and connected to a digital DC power. The aqueous solution (tap water + clomazone) with initial pH close to 7.9 was always treated at ambient temperature (≈20 °C) and atmospheric pressure for 5,400 s. For a confidence level of 95% the rate constant of electrocoagulation and the efficiency of removal of clomazone at equilibrium were 2.1 × 10(-3) ± 0.5 × 10(-3) s(-1) and 97.7 ± 2.2%, respectively. The final chemical oxygen demand was 88% lower than that measured initially, while turbidity and apparent color were totally removed from the synthetic solution at a rate close to that of formation of aluminum hydroxides. Some reaction intermediates, such as benzonitrile-2-chloro and 2-chloro-hex-2,4-diene-1,6-dioic-acid determined by gas chromatography mass spectrometry (GC-MS) analysis, explain the ratio of equilibrium to initial total organic carbon approximately between 0.6 and 0.8 at a probability of 95%.
authors.affiliation: Federal University of Rio Grande, School of Chemistry and Food, Santo Antônio da Patrulha, Rio Grande do Sul, Brazil.
authors.forename: Cristina
authors.initials: C
authors.lastname: Benincá
authors.affiliation: Federal University of Rio Grande, School of Chemistry and Food, Santo Antônio da Patrulha, Rio Grande do Sul, Brazil.
authors.forename: Fernanda T
authors.initials: FT
authors.lastname: Vargas
authors.affiliation: Federal University of Rio Grande, School of Chemistry and Food, Santo Antônio da Patrulha, Rio Grande do Sul, Brazil.
authors.forename: Manoel L
authors.initials: ML
authors.lastname: Martins
authors.affiliation: Federal University of Rio Grande, School of Chemistry and Food, Santo Antônio da Patrulha, Rio Grande do Sul, Brazil.
authors.forename: Fábio F
authors.initials: FF
authors.lastname: Gonçalves
authors.affiliation: Technical School São João Batista, Montenegro, Rio Grande do Sul, Brazil.
authors.forename: Rodrigo P
authors.initials: RP
authors.lastname: Vargas
authors.affiliation: Academic Center of Civil Engineering, Federal University of Technology, Curitiba, Paraná, Brazil.
authors.forename: Flavio B
authors.initials: FB
authors.lastname: Freire
authors.affiliation: Department of Chemical Engineering, Federal University of Paraná, Curitiba, Paraná, Brazil E-mail: everton.zanoelo@ufpr.br.
authors.forename: Everton F
authors.initials: EF
authors.lastname: Zanoelo
mesh_terms: D000535:Aluminum / Q000032:analysis; D004560:Electricity; D004566:Electrodes; D006540:Herbicides / Q000737:chemistry*; D007555:Isoxazoles / Q000737:chemistry*; D023303:Oxazolidinones / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D006540:Herbicides; D007555:Isoxazoles; D023303:Oxazolidinones; D014874:Water Pollutants, Chemical; C095255:clomazone; D000535:Aluminum