Fe–In2O3 Induced Catalytic Degrading Congo Red under Ultrasonic Irradiation.

In this work, the azo dye Congo red (CR) was degraded by a Fe–In2O3 catalyst under the irradiation of ultrasonic. The Fe–In2O3 catalyst was prepared by a fast and moderate solvothermal method followed by the characterization of X-ray diffraction and scanning electron microscope. The effects of operating parameters, such as catalyst composition, catalyst dosage, initial dye concentration, ultrasonic power and ultrasonic frequency on degradation process were discussed. In the experiment, the optimum CR removal of 97.75% in 60 min was achieved under the conditions, i.e., catalyst dosage of 0.06 g ⋅ L − 1 , CR concentration of 10 mg ⋅ L − 1 , ultrasonic frequency of 45 kHz and ultrasonic power of 100 W. Besides, the CR degradation behavior by the catalyst with ultrasonic is well in accordance with the first-order kinetic model. A spherical Fe–In2O3 nanocatalyst with good crystalline structure was successfully synthesized, and the excellent catalytic degradation efficiency for the azo dye congo red under ultrasonic irradiation was shown. The congo red degradation process was fostered by Fe–In2O3 catalyst compared with that of the blank and pure In2O3, which is well in accordance with the first order kinetic model. [ABSTRACT FROM AUTHOR]