Study On Degradation Of Antibiotics By Heterogeneous Photo-fenton

Most antibiotic wastewater is highly toxic and difficult to degrade.Conventional water treatment technology,such as adsorption,precipitation,and biological degradation,has been already not satisfied the requirements of antibiotic wastewater treatment.However,advanced oxidation technology possesses a very broad prospect for the removal of organic contaminants in antibiotic wastewater.Particularly,photo-assisted Fenton heterogeneous system owns an excellent removal effect for antibiotic wastewater,due to the generated free radicals with high oxidation potential.In this study,ciprofloxacin and sulfamethoxazole antibiotics were selected as the research object.For these two antibiotics,the degradation effect of UV/heterogeneous Fenton system,reaction kinetics,reaction mechanism and recycling performance of the catalyst were analyzed.Herein,the theoretical guidance and experimental basis for the treatment of antibiotic wastewater were provided.In this paper,Na-Y type molecular sieves and Ls-5000 amino phosphoric acid chelate resin type Fe2+ catalysts were prepared by impregnation and oscillation method.And under the UV light,two different types of Heterogeneous Fenton catalysts were studied to degrade ciprofloxacin and sulfamethoxazole.The results showed that the two catalysts both have eminent photocatalytic oxidation effect for ciprofloxacin and sulfamethoxazole.Thus,it can be used for the degradation of these two antibiotics.Furthermore,these two catalysts have a reusable performance,which is beneficial for reducing environmental pollution.The degradation of ciprofloxacin and sulfamethoxazole by UV/ heterogeneous Fenton system was analyzed.The factors,such as the amount of iron catalyst,the volume of hydrogen peroxide,the initial concentration of antibiotic solution,the initial pH and ultraviolet light power,were determined by a series of single factor tests.Under the UV light,orthogonal experiment based on four significant factors was carried out.Therefore,the optimum process conditions to degrade ciprofloxacin and sulfamethoxazole were obtained.By comparing the degradation effects of different reaction systems for two antibiotics,it is observed that UV/H₂O₂/Fe???/Na-Y system demonstrated the highest degradation effect.And two catalysts have good recycling properties.The degradation kinetics and degradation mechanism of ciprofloxacin and sulfamethoxazole in UV/heterogeneous Fenton system were also studied.By analyzing the UV-Vis absorption spectra of two kinds of antibiotics before and after the reaction,it is proved that the two kinds of antibiotics under the system have been degraded well.Owing to the strong oxidation effect of hydroxyl radicals,the antibiotics have been oxidized and decomposed finally.