Résumé
This study examined the possibility to remove colour causing-compounds from synthetic effluent by indirect electrochemical oxidation using iridium oxide anode electrodes. Using a high concentration of chloride ions (17.1 mM) and various current densities, it was possible to produce high concentration of active chlorine with a specific production rate of 2.8 mg min
−1
A
−1
. The best performance for acid methyl violet 2B dye (MV2B) decomposition was obtained using Ti/IrO
2
anodes operated at a current density of 15 mA cm
−2
during 40 min of treatment in the presence of 3.42 mM of chloride ions. Under these conditions, more than 99% of MV2B was removed (with a reaction rate apparent constant of 0.20 min
−1
), whereas COD and TOC removal were 51% and 75%, respectively. The electrolytic cell was then used for the degradation of three other synthetic dye solutions: Eosin yellowish (EOY), Trypan Blue (TRB), Acridine Orange (ACO). TRB was the most difficult dye to remove from solution with a value reaction rate constant of 0.12 min
−1
, compared to 0.19 min
−1
and 0.24 min
−1
recorded for ACO and EOY dyes, respectively. More than 99% of these dyes were removed by electrochemical oxidation.