| During the past two decade, hydroxyl radical (OH.) chemistry has attracted wide interest in oxidation technologies in wastewater treatment. The homogeneous Fenton and Photo-Fenton reaction has been commonly used as the source of OH. radicals, but the limitation in such an application is the necessary condition of acidic media and the difficulty of the catalyst disposal and recycle. Recently, some heterogeneous catalysts have been designed for degradation of pollutants, such as metal complexes supported on the polymer membrane or ion-exchange resin and encapsulated in zeolite. It inaugurate a bran-new field of research.In this paper we report a novel catalyst prepared by supporting the Fe(III) complex of sulfonic salicylic onto a strong basic ion-exchange resin(Amberlite IRA 900). This simple heterogeneous catalyst can efficiently trigger the photooxidation reaction of organic pollutants by H2O2 at more wide range of pH under visible light irradiation, even mineralize the substrates.Several model nonbiodegradable pollutants, such as Orange II , sulforhodamine B(SRB), 2,4-dichlorophenol(DCP), rhodamine B(RhB) and pentachlorophenol(PCP), as the target pollutants, was carried out to be photo-oxidated in this system. Several effects to the photo reaction was investigated by using the UV-Vis Spectrophotometer, Gas Chromatograph ,Total Organic Carbon, High Pressure Liquid Chromatograph, Ion Chromatagraph and Fluorescence Spectrum, and measured the rate of the mineralization, TON and life of the catalyst. We also characterized the catalyst through X-ray Photoelectron Spectroscopy and UV-Vis Reflectant Spectrum. Form the results of the experiments, we get a catalyst with high stability, activity and selectivity, andadapts to more wide range of pH, and distinctly increases the use-rate ofand will be easily recycled. By means of modern analysis technique Electron spinresonance (ESR) and other results, a photo reaction mechanism was proposed.
|
PDF Full Text Request