Electro-oxidation of the dye azure B: kinetics, mechanism, and by-products. Academic Article uri icon

abstract

  • In this work, the electrochemical degradation of the dye azure B in aqueous solutions was studied by electrochemical advanced oxidation processes (EAOPs), electro-Fenton, and anodic oxidation processes, using Pt/carbon-felt and boron-doped diamond (BDD)/carbon-felt cells with HO electrogeneration. The higher oxidation power of the electro-Fenton (EF) process using BDD anode was demonstrated. The oxidative degradation of azure B by the electrochemically generated hydroxyl radicals (()OH) follows a pseudo-first-order kinetics. The apparent rate constants of the oxidation of azure B by ()OH were measured according to pseudo-first-order kinetic model. The absolute rate constant of azure B hydroxylation reaction was determined by competition kinetics method and found to be 1.1910(9) M(-1) s(-1). It was found that the electrochemical degradation of the dye leads to the formation of aromatic by-products which are then oxidized to aliphatic carboxylic acids before their almost mineralization to CO and inorganic ions (sulfate, nitrate, and ammonium). The evolution of the TOC removal and time course of short-chain carboxylic acids during treatment were also investigated.

published proceedings

  • Environ Sci Pollut Res Int

author list (cited authors)

  • Olvera-Vargas, H., Oturan, N., Aravindakumar, C. T., Paul, M., Sharma, V. K., & Oturan, M. A.

citation count

  • 26

complete list of authors

  • Olvera-Vargas, Hugo||Oturan, Nihal||Aravindakumar, CT||Paul, MM Sunil||Sharma, Virender K||Oturan, Mehmet A

publication date

  • July 2014