Plasma-catalytic degradation of tetracycline hydrochloride over Mn/γ-Al₂O₃ catalysts in a dielectric barrier discharge reactor

A coaxial dielectric barrier discharge (DBD) reactor was used for plasma-catalytic degradation of tetracycline hydrochloride over a series of Mn/γ-Al₂O₃ catalysts prepared by the incipient wetness impregnation method. The combination of plasma and the Mn/γ-Al₂O₃ catalysts significantly enhanced the degradation efficiency of tetracycline hydrochloride compared to the plasma process alone, with the 10% Mn/γ-Al₂O₃ catalyst exhibiting the best tetracycline hydrochloride degradation efficiency. A maximum degradation efficiency of 99.3% can be achieved after 5 min oxidation and a discharge power of 1.3 W, with only 69.7% by a single plasma process. The highest energy yield of the plasma-catalytic process is 91.7 gkWh⁻¹. Probable reaction mechanisms of the plasma-catalytic removal of tetracycline hydrochloride were also proposed.