Visible light-based photocatalytic ozonation of DCF over CQDs/FeTiO3 heterostructure in a spinning disk photocatalytic reactor

Photocatalytic ozonation is an advanced oxidation process (AOP) that has recently demonstrated its strong oxidation capabilities for efficient wastewater treatment using sunlight and air as the ozone source. Additionally, the spinning disc photocatalytic reactor (SDPR) has been widely adopted recently as an intensification approach for photocatalytic processes. Herein, an efficient approach has been adopted to enhance the degradation performance of photocatalytic ozonation process over CQDs/FeTiO 3 photocatalyst film in a SDPR for synergistically enhancing the degradation of diclofenac sodium (DCF). The DCF degradations were compared in different treatment systems in the SDPR, including ozonation, catalytic-ozonation, photocatalysis, and photocatalytic ozonation. High photocatalytic ozonation performance (99.3% degradation efficiency, 85.8% mineralization, and high stability after six runs) has been acquired over CQDs/FeTiO 3 photocatalyst film under visible-light exposure. The effective separation of photogenerated charge carriers due to CQDs deposition, and high generation of ORS resulting from the combined systems were responsible for the enhanced photocatalytic performance.