Evaluation of trans-ferulic acid degradation by dielectric barrier discharge plasma combined with ozone in wastewater with different water quality conditions

In this study, dielectric barrier discharge plasma and ozone (O₃) were combined to synergistically degrade trans-ferulic acid (FA), and the effect of water quality on FA degradation was studied. The results showed that 96.9% of FA was degraded after 40 min treatment by the plasma/O₃ process. FA degradation efficiency increased with the pH values. The presence of suspended solid and humic acid inhibited FA degradation. FA degradation efficiency increased as the water temperature increased to 30 °C. However, the further increase in water temperature was adverse for FA degradation. Effects of common inorganic ions on FA degradation were also investigated. The addition of Cl ^- inhibited the FA degradation, while CO₃^{2 -} had both negative and positive influences on FA degradation. NO^-₃ and SO₄^{2 -} did not have significant effect on FA degradation. Fe³⁺ and Cu²⁺ benefited FA degradation through the Fenton-like and catalytic ozonation reactions.