Journal of the Mexican Chemical Society
versión impresa ISSN 1870-249X
NAVA, José L.; QUIROZ, Marco A. y MARTINEZ-HUITLE, Carlos A.. Electrochemical Treatment of Synthetic Wastewaters Containing Alphazurine A Dye: Role of Electrode Material in the Colour and COD Removal. J. Mex. Chem. Soc [online]. 2008, vol.52, n.4, pp. 249-255. ISSN 1870-249X.
The electrochemical oxidation of Alphazurine A (αzA) has been studied in Na2SO4 media at Ti/IrO2, Pb/PbO2 and boron-doped diamond (Si/BDD) electrodes by bulk electrolysis experiments under galvanostatic control at j = 30 and 60 mA cm-2. The obtained results have clearly shown that the electrode material plays an important role for the electrochemical incineration of azA, where Pb/PbO2 and Si/ BDD lead complete mineralization of dye, while Ti/IrO2 disfavoured such process. The complete mineralization of ±zA on Pb/PbO2 and Si/BDD is due to the production of hydroxyl radicals on these materials surfaces. Current efficiencies obtained at Ti/IrO2, Pb/PbO2 and Si/ BDD gave values of 3, 24 and 42%, for each electrode material, at 30 mA cm-2, respectively. These values were higher than those obtained at 60 mA cm-2. Energy consumption values from the electrolyses performed at 30 mA cm-2 were 254, 124 and 51 kWh m-3, for Ti/IrO2, Pb/PbO2 and Si/BDD, respectively. UV spectrometric measurements showed faster αzA elimination at the Si/BDD electrode than those obtained on Ti/IrO2 and Pb/PbO2.
Palabras llave : Anodic oxidation; dyes; boron doped diamond electrode; iridium dioxide electrode; lead dioxide electrode.