Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water
| Autor: | Gustavo A. Peñuela, Ricardo E. Palma-Goyes, Ignacio González, Fernando L. Guzmán-Duque, Ricardo A. Torres-Palma |
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| Rok vydání: | 2014 |
| Předmět: |
Environmental Engineering
Supporting electrolyte Health Toxicology and Mutagenesis Inorganic chemistry chemistry.chemical_element Electrolyte Iridium Waste Disposal Fluid chemistry.chemical_compound Chlorides Electrochemistry Environmental Chemistry Crystal violet Coloring Agents Waste Management and Disposal Electrodes Boron Pollutant Chemistry Sulfates Pollution Anode Degradation (geology) Water treatment Gentian Violet Diamond Water Pollutants Chemical |
| Zdroj: | Journal of hazardous materials. 278 |
| ISSN: | 1873-3336 |
| Popis: | Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO2) used as anode materials were tested with Na2SO4 or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode-electrolyte interaction. With BDD, the degradation pathway depends on i: If ithe limiting current density (i(lim)), CV is mainly degraded by OH radicals, whereas if ii(lim), generated oxidants play a major role in the CV elimination. When IrO2 was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na2SO4 on IrO2 seems to occur via IrO3; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na2SO4 electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO2. Thus, the IrO2/Cl(-) and BDD/SO4(2-) systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO4(2-) and IrO2/Cl(-) systems is favored at low and high current densities, respectively. |
| Databáze: | OpenAIRE |
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