Publications (4)9.94 Total impact
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Article: Electrochemical degradation of an anionic surfactant on boron-doped diamond anodes.
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ABSTRACT: In this work, the electrochemical oxidation on boron-doped diamond of synthetic wastes polluted with surfactant sodium dodecylbenzenesulfonate (SDBS) has been studied. Results show that SDBS can be successfully removed with this technology inside different current densities and concentration ranges. The oxidation of the SDBS seems to occur in two main sequential steps: the first is the rapid degradation of SDBS, and the final is the less efficient oxidation of aliphatic intermediates to carbon dioxide. The nature of supporting electrolyte (NaCl, Na(2)SO(4) and K(3)PO(4)) influences on the efficiency of the electrochemical oxidation process. The treatment of the NaCl solution seems to be more efficient in the chemical oxygen demand (COD) removal, while the sulphate and specially the phosphate media improve the TOC removal. However, in spite of this observation, chemical oxidation of SDBS by different types of oxidants cannot explain alone the results of the electrochemical oxidation with diamond anodes. This suggests that the synergistic effect of the different oxidation mechanisms that occurs into the electrochemical cell (direct oxidation and mediated oxidation by hydroxyl radicals and by oxidants formed from the electrolyte) is the responsible of the great efficiencies obtained with this technology in the treatment of organics.Journal of Hazardous Materials 03/2008; 158(2-3):430-7. · 4.17 Impact Factor -
Article: Electrochemical treatment of the pollutants generated in an ink-manufacturing process.
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ABSTRACT: The effluents of ink-manufacturing processes contain a large variety of pollutants such as dyes, surfactants, biocides, water soluble solvents, etc. In this work, the electrochemical oxidation of several dyes (methylene blue and rhodamine B), solvents (monoethylene glycol, diethylene glycol and glycerol) and surfactants (sodium dodecylbenzenesulfonate) has been studied. To carry out the electrolyses, a bench-scale plant with a single-compartment electrochemical flow-cell was used. Boron doped diamond (BDD) was used as anode and stainless steel (AISI 304) as cathode. For all the compounds tested, the conductive diamond electrooxidation allows achieving the almost complete removal of COD of the waste with a very high current efficiency. The efficiencies of the electrochemical processes seem to depend on the current density and on the nature of the anions contained in the waste (chlorine, sulphate, phosphate). Thus, it has been observed that the use of chloride media favours the treatment of dyes. On the contrary, the use of sulphate- or phosphate-containing solutions improves the removal of the aliphatic compounds studied (solvents). These results suggest an important role of the mediated electrochemical processes on the overall performance of the reaction system.Journal of Hazardous Materials 08/2007; 146(3):552-7. · 4.17 Impact Factor -
Article: Electrochemical Oxidation of Benzoic Acid Derivatives on Boron Doped Diamond: Voltammetric Study and Galvanostatic Electrolyses
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ABSTRACT: The electrochemical oxidation of aqueous wastes polluted with benzoic and salicylic acids and phthalic anhydride on boron-doped diamond electrodes has been studied. The complete mineralization of the organic waste has been obtained in each case regardless of the nature of the compound, composition of the solution, and current density. Different voltammetric behaviors between benzoic acid, salicylic acid, and phthalic anhydride were obtained in the voltammetric study, but no differences in the electrochemical oxidation of the three compounds seems to exist in the bulk electrolyses study. The total mineralization of the three compounds at different current densities confirms that the oxidation must occur directly on the electrode surface and/or by hydroxyl radicals generated by decomposition of water and/or by other oxidants electro-generated from the sulfate oxidation.Chemical Engineering & Technology 08/2006; 29(8):944 - 950. · 1.60 Impact Factor -
Article: Electrochemical degradation of an anionic surfactant on boron-doped diamond anodes
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ABSTRACT: In this work, the electrochemical oxidation on boron-doped diamond of synthetic wastes polluted with surfactant sodium dodecylbenzenesulfonate (SDBS) has been studied. Results show that SDBS can be successfully removed with this technology inside different current densities and concentration ranges. The oxidation of the SDBS seems to occur in two main sequential steps: the first is the rapid degradation of SDBS, and the final is the less efficient oxidation of aliphatic intermediates to carbon dioxide. The nature of supporting electrolyte (NaCl, Na2SO4 and K3PO4) influences on the efficiency of the electrochemical oxidation process. The treatment of the NaCl solution seems to be more efficient in the chemical oxygen demand (COD) removal, while the sulphate and specially the phosphate media improve the TOC removal. However, in spite of this observation, chemical oxidation of SDBS by different types of oxidants cannot explain alone the results of the electrochemical oxidation with diamond anodes. This suggests that the synergistic effect of the different oxidation mechanisms that occurs into the electrochemical cell (direct oxidation and mediated oxidation by hydroxyl radicals and by oxidants formed from the electrolyte) is the responsible of the great efficiencies obtained with this technology in the treatment of organics.Journal of Hazardous Materials.