Degradation of Aniline by Bismuth Oxyiodide (BiOI) under Visible Light Irradiation
Visible-light-driven porous spherical photocatalyst bismuth oxyiodide (BiOI) was successfully prepared by facial hydrothermal synthesis. The obtained catalyst was characterized using x-ray diffraction (XRD), ultraviolet-visible diffuse reflection (UV-Vis DRS) and scanning electron microscope (SEM). The experiment which used the visible-driven catalyst to degrade aniline wastewater investigated the effects of initial concentration of aniline and reaction time on the removal efficiency of aniline. The highest photodegradation efficiency of aniline was 97.3% with a BiOI dosage of 1 g L-1 and initial aniline concentration of 50 mg L-1 after 2 h of visible light irradiation. The chemical oxygen demand (COD) of the solution decreased substantially and the high chemical oxygen demand removal efficiency achieved 71%. In addition, the investigation of different scavengers demonstrated that h+ and •O2− are the main reactive species in the photodegradation of aniline. The fate of nitrogen was investigated by ion chromatography. The high photodegradation and mineralization capability efficiency suggest BiOI is a promising photocatalyst for the degradation of organic pollution in the practical application.