Electrooxidative Degradation of an Anthraquinone Dye with in-situ Electrogenerated Active Chlorine in a Divided Flow Cell

The purpose of this paper was to investigate the possibility of treating C.I.Reactive Blue 19 wastewater by electrochemical oxidation via electrogenerated active chlorine,using metallic oxide coatings(dimensional stable anode,DSA)as anode.The electrolysis for the simulated wastewater was conducted at a constant current. Absorbances at 592 nm and 255 nm were measured to follow the decolorization of the dye and the degradatin of its aromatic ring.After 4 h of electrolysis under the experimental conditions:current density of 15 A.m,0. 2 mol.LNaCl,0. 1 mol.LNaSO,0. 1 mmol.Ldye,initial pH=6. 4 and T=30℃,100% decolorization of the dye and about 45% degradation of its aromatic ring were achieved,while no obvious change of total organic carbon was observed.The experimental results suggest that the decolorization of the dye and degradation of its aromatic ring were directly affected by current density,temperature,concentrations of the dye and sodium chloride,while slightly affected by initial pH and sodium sulfate concentration;the decolorization of the dye and degradation of its aromatic ring followed pseudo-first-order kinetics;and indirect electrooxidation,using electrogenerated active chlorine,predominated in the electrochemical oxidation.