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This paper reports on the process of industrial-type wastewater purification carried-out through continuous anodic dissolution of aluminum alloy sacrificial anode for artificially aerated Cu-Al alloy galvanic (macro-corrosion) cells and synthetically prepared wastewater solutions. Electrochemical experiments were performed by means of a laboratory size electrolyzer unit, where the electrocoagulation process along with surface-induced electrooxidation phenomena were examined for wastewater containing Acid Mixture and Disperse Red 167 dyes. Final reduction of the dyes concentrations came to 32 and 99% for Acid Mixture and Disperse Red 167, correspondingly. The above was visualized through the employment of electrochemical (cyclic voltammetry and a.c. impedance spectroscopy techniques) and instrumental spectroscopy analyses.

Electrochemical oxidation of resorcinol on a polycrystalline platinum electrode was investigated in five different solutions, namely 0.5 and 0.1 M H2SO4, 0.5 M Na2SO4, 0.5 and 0.1 M NaOH. The rates of electrochemical degradation of resorcinol were determined based on the obtained reaction parameters, such as resistance, capacitance and current-density. The electrochemical analyses (cyclic voltammetry and a.c. impedance spectroscopy) were carried-out by means of a three-compartment, Pyrex glass cell. These results showed that the electrochemical oxidation of resorcinol is strongly pH-dependent. In addition, the energy dispersive X-ray (EDX) spectroscopy technique was employed for Pt electrode surface characterization. Additionally, the quantitative determination of resorcinol removal was performed by means of instrumental high-performance liquid chromatography/mass spectrometry (HPLC/MS) methodology.

Electrochemical oxygen evolution reaction (OER) activity was studied on nickel foam-based electrodes. The OER was investigated in 0.1 M NaOH solution at room temperature on as-received and Co- or Mo-modified Ni foam anodes. Corresponding values of charge-transfer resistance, exchange current-density for the OER and other electrochemical parameters for the examined Ni foam composites were recorded. The electrodeposition of Co or Mo on Ni foam base-materials resulted in a significant enhancement of the OER electrocatalytic activity. The quality and extent of Co, and Mo electrodeposition on Ni foam were characterized by means of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analysis.

The present paper reports AC impedance spectroscopic/Tafel polarization and cyclic voltammetry study on the influence of acetonitrile concentration on the kinetics of UPD of H (underpotential deposition of hydrogen) and HER (hydrogen evolution reaction), examined on polycrystalline and polyoriented single-crystal sphere Pt electrode surfaces in 0.5 M H2SO4 and 0.1 M NaOH supporting solutions. The resulted data provided confirmation of the destructive role of Pt surface-electrosorbed acetonitrile on the kinetics of underpotentially deposited hydrogen, as well as cathodic hydrogen evolution reaction. The above was exclusively elucidated through evaluation of the associated charge-transfer resistance and capacitance (and complementary exchange current-density and Tafel slope) parameters, derived comparatively on Pt for pure and acetonitrile-modified acidic and alkaline electrolytes.