Study On Catalytic Degradation Of Organic Wastewater By Modified Bismuth Tungstate

The complexity of organic wastewater makes it difficult to be treated effectively and thoroughly with the conventional water treatment technology,what's worse,its large amount of non-compliance emissions of pollutants in the environment enrichment,which has brought great harm to the ecological environment and human health.Therefore,the research and development of new water treatment technology has become an imminent issue.In this paper,two different iron doped bismuth tungstate photocatalysts were synthesized by solvothermal method and hydrothermal method.The textures of materials were observed by X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy dispersive spectroscope(EDS).The results show that the synthesized samples are orthorhombic bismuth tungstate micrometer semiconductor materials,and EDS analysis shows that iron ions are successfully doped into the bismuth tungstate lattice,and doped with iron was not obvious influence on the morphology and size of the samples,which were micro-spherical and flower-like structure.The water quality of dye wastewater is the most representative in the more difficult organic wastewater.The sonocatalytic activities of catalysts were tested by the degradation of Congo red in dye wastewater,the synthesis of two kinds of iron doped bismuth tungstate semiconductor as catalyst,studied the ultrasonic degradation effect of the catalyst on Congo red simulated wastewater with the action of the ultrasonic cavitation,and the reaction kinetics model was fitted to the different influencing factors of the catalytic reaction in the best experimental conditions.The results show that:1)The degradation performance of ultrasonic synergistic modified catalyst is better than that of single ultrasonic wave,and the degradation performance of bismuth tungstate is better than that of undoped,which indicates that the doping of iron ions improves the catalytic activity of the catalyst;2)The ultrasonic degradation effect of Congo red wastewater will be affected by different factors such as iron doping amount,catalyst dosage,initial concentration of solution and pH value,ultrasonic frequency and power,and in the cycle experiment shows that the catalyst has good stability;3)Under the optimum conditions,the reaction kinetics study on different influential factors of the catalytic reaction was taken,and the results showed a remakable linear dependence between the fitting line,demonstrating a high fitting degree of R2 which was higher than 0.96.Therefore,it can be concluded that the process of ultrasonic catalytic reaction followed the first-order kinetics model.