In this work, the electrooxidation as environmentally clean technology has been studied to the degradation of Mordant Blue 13 azo dye (MB13) using boron-doped diamond (p-Si/BDD) and oxide ruthenium titanium (Ti/RuTiO (DSA)) anodes in various water matrices: distilled water (DW), hot tap water (HTW), and simulated wastewaters with (SWS) and without surfactant (SW). The influence of experimental parameters, such as current density, initial dye concentration, electrolysis time/specific charge, and pH on the MB13 degradation rate, current efficiency, and energy consumption, has been determined. The enhanced rate of both color and chemical oxygen demand (COD) removal in sulfate aqueous solutions with BDD was observed, which indicates that sulfate (SO) radicals along with OH ones might be responsible for the degradation process. The MB13 decolorization process obeyed a pseudo-first-order reaction kinetics with the apparent rate constant from 7.36 × 10 min to 4.39 × 10 min for BDD and from 9.2 × 10 min to 2.11 × 10 min for DSA depending on the electrolysis conditions. The effect of water matrix on the decolorization and COD removal efficiency has been evaluated. Inorganic ions, mordant salt, and surfactant contained in simulated effluents decelerated the COD decay compared to DW and HTW for the both anodes; meanwhile, they differently affected the discoloration process. A comparison of the specific energy consumption for each electrocatalytic material under different experiment conditions has been made. The BDD electrode was more efficient than the DSA to oxidize the MB13 dye in all kinds of water.

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Electrocatalytic oxidation of aromatic pollutants (aniline, Methyl Orange, Eriochrome blue SE) is studied on lead dioxide, boron doped diamond, and ruthenium-and titanium-oxide-based anodes (DSA, dimensionally stable anode). The catalytic properties of the tested materials are studied using cyclic voltammetry and galvanostatic electrolysis. The activity of electrodes toward the electrochemical conversion of organics is shown to increase in the sequence of DSA < lead dioxide < boron doped diamond. The oxidation rate decreases in the order of Eriochrome blue SE > Methyl Orange > aniline for all electrodes. The oxidation process of the compounds corresponds to the pseudo-first-order reaction kinetics. The apparent rate constant grows at an increase in the applied current density and decrease in the initial pollutant concentration.The formation of both • OH and radicals is confirmed by the free radical quenching studies; their contribution to the Eriochrome blue SE dye destruction process is evaluated.

Electrocoagulation treatment of model wastewater solutions to remove jointly present Cu 2+ and Ni 2+ ions was studied. The infl uence of the current density, concentration of impurities, anode material, and structure of the precipitate of coagulant metal hydroxides on the effi ciency of removal of the heavy metal ions was examined. The decisive factor under the chosen process conditions is the anode material. The electrocoagulation effi ciency is considerably higher when using the aluminum anode, compared to the iron anode.