Effect of electrode shape and deposition technique on electrochemical treatment of ampicillin in water

The effect of stainless steel (SS) electrode shape on electrochemical treatment of pharmaceutical pollutant has been studied. Anodes consisting of SS plate and SS grid coated with lead dioxide (PbO2) were prepared by different deposition techniques: electrodeposition (ED), sol gel method (SG) using spin-coating (SC) and dip-coating (DC) depending on the electrode shape. The influence of the substrate shape and the deposition method on the oxidizing performance of the elaborated electrode was studied. The surface morphology and the composition of the PbO2 layer were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). XRD analysis revealed the presence of β -PbO2 form with both deposition techniques in addition to the chromium (Cr) phase attributed to the SS substrate. Electrochemical Impedance Spectroscopy (EIS) measurements were performed for assessing the electrochemical behavior of the SS/PbO 2 anodes. EIS results demonstrated a smaller charge transfer resistance with PbO2 ED coating compared to PbO2 SG . The degradation of ampicillin as pharmaceutical pollutant was evaluated with high performance liquid chromatography and chemical oxygen demand (COD) for overall mineralization of organic matter and to evaluate the related average current efficiency (ACE) and energy consumption (EC). This study demonstrated that SS grid /PbO 2 ED is the most efficient electrode for electrochemical treatment with 100% of ampicillin removal after 120 min of treatment.