Electrochemical Oxidation Treatment Of Antibiotic Wastewater By Electrochemical Reduction And P-doped TiO₂ Nanotubes Anodes

The pollution problem caused by the massive use of antibiotics has caused widespread concern.Electrochemical oxidation technology has the advantages of simple operation and strong environmental adaptability,which is a new type of water treatment technology.Efficient anode materials are the key to the treatment of organic wastewater by electrochemical advanced oxidation.At the same time,in the face of complex polluted water bodies,the simultaneous removal of pollutants is also a very important research hotspot.In this paper,two kinds of TiO₂nanotube（TiO₂ NTAs）electrode materials were prepared as anodes for the treatment of antibiotic wastewater by electrochemical oxidation,a series of characterization confirmed the electrode structure and electrochemical oxidation performance.One was Ti³⁺ and oxygen vacancy self-doped TiO₂ NTAs(TiO_2-x)by eletrohemial reduction.XPS,Raman,EPR proved the doping of oxygen vacancies,electrochemical tests showed that the doping of Ti³⁺and oxygen vacancies enhances the electrochemical performance of electrode materials.LSV indicated the electrode with a reduction time of 10 min(TiO_2-x-10)has the highest oxygen evolution potential（OEP）（3.01 V vs.SCE）.Electrochemical oxidation experiments on tetracycline were carried out using TiO_2-x electrodes under different reduction times.The results showed that TiO_2-x-10 electrodes had the best degradation effect on tetracycline.Using the TiO_2-x-10 electrode as the anode,co-removal of tetracycline and metronidazole at a current density of 10 m A/cm²,after 3 h treatment,both antibiotics can be completely removed,and the chemical oxygen demand（COD）removal rate was 79.12%.The energy consumption required for simultaneous degradation of two antibiotics through energy consumption analysis was lower than the energy consumption of degrading a single antibiotic,indicating that simultaneous removal of two antibiotics can not only achieve efficient removal effects,but also save energy,which is more suitable for practical applications.The second was phosphorus and oxygen vacancy co-doped TiO₂ NTAs(P-TiO_2-y),Raman,EPR proved the doping of oxygen vacancies,electrochemical tests showed that the doping of Ti³⁺and oxygen vacancies enhance the electrochemical performance of electrode materials.Phosphorus doping increases the electrode’s OEP,LSV indicated that the OEP of the P-TiO_2-yis 2.98 V vs.SCE.Experiments show that the improvement of the degradation performance of tetracycline by phosphorus doping is mainly reflected in the COD removal rate.After 3 h treatment at a current density of 10 m A/cm² and an initial concentration of 50 mg/L,the TC removal rate,COD removal rate and total organic carbon（TOC）removal rate were 100%,90.32%and 76.60%,respectively.