Heterogeneous Photo‐Fenton Catalytic Oxidation of Ciprofloxacin Using LaFeO <sub>3</sub> /Diatomite Composite Photocatalysts under Visible Light
Ying Liu, Min Wu, Lili Ren, Chuanchuan Wang, Zhihao Li, Liwei Ling, Yuting Guo
Abstract
Abstract LaFeO 3 /Diatomite porous disk composites have been successfully prepared by sol‐gel method for the photocatalytic oxidative degradation of ciprofloxacin (CIP) compounds. The structure of the porous disc plays an important role in improving the photocatalytic activity by increasing the contact area between the photocatalyst and CIP to enhance CIP molecule adsorption. Meanwhile, the porous disk composite photocatalysts can effectively prevent the recombination of light‐induced electron‐hole pairs. A photo‐Fenton‐like reaction is triggered by addition of H 2 O 2 , which further remarkably improves the photocatalytic activity of LaFeO 3 /Diatomite. Then, the factors like catalyst concentration, H 2 O 2 dosage, initial pH and CIP concentration of the solution responsible for the enhanced photocatalytic performance of the reaction system are investigated. The optimal degradation rate of ciprofloxacin by the LaFeO 3 /Diatomite catalyst is 99.02 % after visible light irradiation for 150 min, which is 1.22 times of the pure LaFeO 3 . The catalysts have a much high stability which can be recycled for many times and the degradation rate of four cycles is still about 98 %. The excellent performance and high photocatalytic efficiency of the LaFeO 3 /Diatomite photocatalyst make it have potential application foreground in the treatment of pharmaceutical wastewater.