Electrochemical Degradation of Tetracycline on BDD in Aqueous Solutions

This study focuses on the electrochemical oxidation of tetracycline hydrochloride (TC-HCl) on a boron-doped diamond (BDD) anode under different operating parameters (current density, temperature, TC initial concentration, and sample matrix). For comparison, a commercial Pt planar electrode and a self-prepared PbO2 electrode were also tested. According to cyclic voltammetric analysis, the oxidation of TC on BDD was electrochemically irreversible. The degradation efficiency of TC increased with increasing current density or temperature, but decreased with increasing initial TC concentration. The BDD anode was superior to the PbO2 and Pt electrodes for TC degradation and total organic carbon (TOC) removal. At 0.1 A/cm2 and 25°C, the pseudo-first-order rate constants of TC electro-degradation on BDD were 1.26×10-3 and 1.10×10-3 s-1 in 0.1 m Na2SO4 solution and municipal wastewater treatment plant secondary effluent, respectively. The sample matrix influenced more on TOC removal than on TC degradation.