Preparation of bulk Au/ZnO/Co3O4-calcined copper foam photocatalyst in reactor for continuous flow degradation of tetracycline hydrochloride

Abstract

At present, the continuous flow (C-F) degradation in reactors cannot be used to remove tetracycline hydrochloride (TCH) in wastewater due to the weak activity of adopted photocatalysts. Herein, a highly active photocatalyst, bulk Au/ZnO/Co₃O₄-calcined copper foam (AZC-C), is controllably prepared. The AZC-C photocatalyst possesses special surface morphology and displays exceptional photocatalytic performance in the C-F degradation of TCH. The enhanced photocatalytic activity of AZC-C can be attributed to the synergistic action of the active component (Au/ZnO/Co₃O₄) and the support (calcined copper foam). Selecting optimized AZC-C photocatalysts as packing materials, the reactor with unique structure is constructed. Based on the reactor, the C-F degradation of TCH is firstly effectively performed. Subsequently, a strategy on the tandem reactor module is put forward to further raise the removal efficiency for TCH. Utilizing the tandem reactor module with five reactors, the removal rate of TCH and the rate constant for the C-F degradation of TCH can be drastically improved to 600 mL/h and 0.5817 min⁻¹, respectively. Noteworthy, the conversion efficiency (CE) of TCH reaches up 100 %. Additionally, the tandem reactor module exhibits desirable operating stability (24 h) and reusability (6 mon) in the C-F degradation of TCH. Obviously, the above tandem reactor module can be widely used in the field of water decontamination.