Electrochemical degradation of chloramphenicol using Ti-based SnO2–Sb–Ni electrode

Antibiotic residues may be very harmful in aquatic environments, because of limited treatment efficiency of traditional treatment methods. An electrochemical system with a Ti-based SnO 2 –Sb–Ni anode was developed to degrade a typical antibiotic chloramphenicol (CAP) in water. The electrode was prepared using a sol–gel method. The performance of electrode materials, impact factors and dynamic characteristics were evaluated. The Ti-based SnO 2 –Sb–Ni electrode was compact and uniform as shown by characterization using SEM and XRD. The electrocatalytic oxidation of CAP was carried out in a single-chamber reactor by using a Ti-based SnO 2 –Sb–Ni electrode. For 100 mg L −1 CAP, the CAP removal ratio of 100% and the TOC removal ratio of 60% were obtained at the current density of 20 mA cm −2 and in a neutral electrolyte at 300 min. Kinetic investigation has shown that the electro-oxidation of CAP on a Ti-based SnO 2 –Sb–Ni electrode displayed a pseudo-first-order kinetic model. Free radical quenching experiments presented that the oxidation of CAP on Ti-based SnO 2 –Sb–Ni electrode resulted from the synergistic effect of direct oxidation and indirect oxidation (·OH and ·SO 4 − ). Doping Ni on the Ti/SnO 2 –Sb electrode for CAP degradation was presented in this paper, showing its great application potential in the area of antibiotic and halogenated organic pollutant degradation. Ti/SnO 2 –Sb–Ni anodes were first applied to remove CAP by electrocatalytic oxidation. The removal ratios of CAP and TOC by anodic oxidation and cathodic reduction were first compared. The degradation of CAP on the Ti/SnO 2 –Sb–Ni electrode results from the synergistic effect of direct oxidation and indirect oxidation (·OH and ·SO 4 − ). ·SO 4 − and direct oxidation contributed much to the degradation of CAP.