Sonocatalytic Degradation Of Organic Dye Wastewater In The Presence Of Semiconductor Materials Tungstate

The Ag₈W₄O₁₆6 and BaWO₄ have been reported that they could be used as photocatalyst for the treatment of organic dyes wastewater.According to the mechanism of sonolysis and photocatalysis and the results of Bi₂WO₆,ZnWO₄ and CoWO₄ for the sonocatalytic degradation and adsorption of organic pollutants,it is speculated that Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ may have good sonocatalytic activity for degradation of organic pollutants.In this paper,the semiconductor materials tungstates(Ag₈W₄O₁₆,BaWO₄,Br^--BaWO₄)catalyst were prepared by the hydrothermal synthesis.The synthetic products were used to sonocatalytic degradation of organic dyes?MO?SY?Rh B?.The sonocatalytic activities of(Ag₈W₄O₁₆,BaWO₄,Br^--BaWO₄)catalysts were determined by the change in absorbance of the maximum absorption peak of the organic dyes using UV-vis.The effects of experimental parameters,such as doping amount of Br ion,pH of hydrothermal synthesis solution,calcination temperature,addition amount of catalyst,solution pH,initial concentration of solution,ultrasonic power and ultrasonic time on the degradation ratio were investigated.In addition,the Zeta potential of the Ag₈W₄O₁₆6 catalyst and organic dye MO was measured.The reaction mechanisms of the sonocatalytic degradation of the organic dyes?MO?SY?Rh B?catalyzed by the catalyst(Ag₈W₄O₁₆,BaWO₄,Br^--BaWO₄),respectively,were discussed by the reactive oxygen species?ROS?scavengers.And the catalyst's reusability were studied.The main results are as follows:?1?Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ prepared by hydrothermal synthesis were characterized by XRD?SEM?FESEM and EDS.Characterization and elemental analysis showed that the Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ particles prepared by the hydrothermal synthesis method were uniformly distributed,with high crystallinity.The elements of the Br^--BaWO₄ catalyst were analyzed using an EDS.The results showed that the Br ion-doped BaWO₄ was successfully prepared.?2?The results indicate that the above experimental parameters have an important influence on the catalytic ultrasonic degradation ratio of MO,SY and Rh B,and the prepared catalysts all exhibit excellent ultrasonic degradation performance and good reusability.?3?The results of ROS scavenger show that the mechanisms of ultrasonic degradation of MO,SY and Rh B catalyzed by Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ all are attributed to the generation of ROS scavenger,respectively,in which both singlet oxygen?¹O₂?and hydroxyl radical??OH?play an important role.?4?The ultrasonic degradation reaction of Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ conforms to the pseudo first-order kinetics.?5?The degradation studies of different dyes?Congo red,Rh B and gold orange II?catalyzed by BaWO₄ show that BaWO₄ has certain sonocatalytic activity for dyes with different structures and properties.The results show that tungstates,Ag₈W₄O₁₆,BaWO₄ and Br^--BaWO₄ all have good application prospects in the treatment of organic dye wastewater,and also provide the theoretical and experimental basis for large-scale ultrasonic treatment of organic dye wastewater.