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

Abstract

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 SnO2–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 SnO2–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 SnO2–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 SnO2–Sb–Ni electrode displayed a pseudo-first-order kinetic model. Free radical quenching experiments presented that the oxidation of CAP on Ti-based SnO2–Sb–Ni electrode resulted from the synergistic effect of direct oxidation and indirect oxidation (·OH and ·SO4−). Doping Ni on the Ti/SnO2–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. HIGHLIGHTS Ti/SnO2–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/SnO2–Sb–Ni electrode results from the synergistic effect of direct oxidation and indirect oxidation (·OH and ·SO4−). ·SO4− and direct oxidation contributed much to the degradation of CAP.;

Keywords

• chloramphenicol
• electrocatalytic
• ti-based sno2–sb–ni electrode