Aqueous tetracycline degradation by non-thermal plasma combined with nano-TiO2

• Non-thermal plasma technology was firstly applied to treat TC wastewater.
• The nano-TiO2 showed efficient synergistic activity with pulsed discharge plasma.
• Identification of intermediates and pathway of TC degradation were evaluated.

The combined application of nanoscale TiO2 and corona discharge plasma for the degradation of tetracycline (TC) in aqueous solution was tentatively investigated. The anatase TiO2 was synthesized by sol–gel method. The basic characteristics of TiO2 were analyzed by XRD, SEM, TEM, BET and XRF. The catalytic property, the decomposition intermediates and the degradation pathway of aqueous TC were also evaluated. The results showed that the nano-TiO2 exhibited excellent catalytic effects on TC degradation. 250 mL TC with initial concentration of 50 mg L−1 could be remarkably improved from 61.9% to 85.1% in 24 min at input discharge power of 36.0 W relative to the TiO2 cooperated as 1.5 g L−1. Meanwhile, the total organic carbon was eliminated from 25.3% to 53.4%. The synthesized catalyst could embody a considerable synergism with the corona discharge plasma in removing TC, and a possible degradation pathway of TC was derived on the basis of the detected intermediates. This research implied a promising application of degrading TC in wastewater treatment.