Electrochemical treatment of antibiotic wastewater containing ceftriaxone sodium by porous Ti/Magnéli Ti4O7 nanotube arrays

Abstract

In this study, porous Ti/Magnéli Ti4O7 nanotube arrays (NTA) was fabricated to pretreat antibiotic wastewater. Characterization of the Ti4O7-NTA illustrated that highly ordered NTA was successfully generated on the porous Ti substrate, which enlarged the specific surface area by 1.67 times. The Ti4O7-NTA has a high oxygen evolution potential (2.60 V) as well as low interfacial charge transfer resistance (4.479 Ω cm−2). Ceftriaxone sodium (CRO) was completely removed from raw antibiotic wastewater after 3 h of treatment by the Ti4O7-NTA, under optimal operation conditions. The biodegradability and toxicity of the wastewater were also significantly enhanced and reduced, as the BOD/COD and EC50,48h values were increased to 0.48 and 57.62 % ± 2.16 %, respectively. The possible degradation pathway of CRO was proposed by LC‒MS. Cathodic polarization was proven to be an effective way to ensure the long-term durability of the Ti4O7-NTA.

Keywords

• Antibiotic wastewater
• Pretreatment
• Electrochemical oxidation
• Magnéli Ti4O7
• Ceftriaxone sodium
• Degradation pathway