Degradation Of Ciprofloxacin Medical Wastewater By Bismuth Tungstate Catalyzed Ultrasound

The abuse of antibiotics has attracted more and more attention of the society,especially a large number of residual antibiotics and their metabolites entering the environment causing pollution.Due to the unsatisfactory effect of traditional wastewater treatment methods,many new wastewater treatment technologies have emerged in recent years.Ultrasound degradation is an advanced method for water purification.Its principle is mainly based on the cavitation effect caused by ultrasound irradiation.In recent years,it has been reported that in the catalytic degradation of organic pollutants,the combination of semiconductor materials and ultrasound has many advantages,such as high degradation rate,environmental protection,relatively simple and feasible methods,and has become an important research direction for the degradation of organic pollutants.In order to find a more effective wastewater treatment method,the ultrasonic degradation of ciprofloxacin catalyzed by bismuth tungstate and the factors affecting its chemical activity were studied.The specific contents are summarized as follows.Firstly,sheet,microsphere and chrysanthemum crystal bismuth tungstate were prepared by hydrothermal synthesis,and their structures were characterized by SEM,EDS and XRD.Then,taking ciprofloxacin as the research object,the effects of preparation conditions such as pH,ultrasonic time,ultrasonic power,amount of catalyst,initial concentration of antibiotics and initial pH of antibiotics on the acoustic catalytic activity of bismuth tungstate crystal were investigated.Secondly,the effects of bismuth oxide doping on the acoustic catalytic activity of bismuth tungstate were investigated.In addition,the effects of ultrasound time,ultrasound power,catalyst dosage,initial concentration of antibiotics and initial pH of antibiotics on the sonic catalytic activity of bismuth tungstate doped with bismuth oxide were further investigated with the degradation rate of ciprofloxacin before and after ultrasound.On this basis,the catalytic degradation of ciprofloxacin by various crystal bismuth tungstate and doped bismuth tungstate under combined acoustic-optical irradiation was studied.The results show that all crystal forms of bismuth tungstate have good acoustic/ photocatalytic activity and stability.Among them,the microspheric crystal bismuth tungstate has the best acoustic catalytic activity,and the degradation rate of ciprofloxacin can reach 94.30%.Doping bismuth oxide can slightly promote the acoustic catalytic activity of bismuth tungstate,and the degradation rate of ciprofloxacin can reach 95.16%.At the same time,the application of Acoustooptic Technology in the catalysis of bismuth tungstate is obviously better than that of ultrasound alone.