Electrochemical removal of fluoxetine via three mixed metal oxide anodes and carbonaceous cathodes from contaminated water

Abstract

In this work, the fluoxetine (FLX) removal has been studied via the anodic oxidation (AO) process. Anode electrodes were Ti/RuO2, Ti/RuO2-IrO2, and Ti/RuO2-IrO2-SnO2, and cathode electrodes were graphite and carbon nanotubes (CNTs). The performances of electrodes were compared in terms of FLX removal efficiency. As a result, Ti/RuO2-IrO2-SnO2 and CNTs were the optimal anode and cathode, respectively. The properties of the optimal electrodes were investigated using scanning electron microscopy, atomic force microscopy and X-ray diffraction spectroscopy. Cyclic voltammetry analysis was performed to study the electrochemical behavior of electrodes. The effect of current intensity (mA), initial pH, initial FLX concentration (mg/L) and process time (min) on the FLX removal efficiency was investigated and the response surface methodology was applied for the optimization of the AO process. The results showed that at current intensity, pH, initial FLX concentration and process time of 500 mA, 6, 25 mg/L and 160 min, maximum FLX removal efficiency was observed, which was 96.25%. Gas Chromatography-Mass Spectrometry (GC-MS), and total organic carbon (TOC) analysis was determined to evaluate the intermediates, and mineralization efficiency. The TOC removal efficiency was reached 81.51% after 6 h under optimal experimental conditions, indicating the successful removal of the FLX.