As Set Of Ag-tio <sub> 2 </ Sub> / Preparation And Photocatalytic Properties Of 4a Molecular Sieves,

At recent years, it has attracted a great deal of attention that·how to improve thephotocatalytic activity of TiO₂ and prepare the photocatalysts which possess highphotocatalytic activity. The paper expatiates on the making process of the Ag- TiO₂/4Azeolite by doing kinds of fumble experiments to make sure and optimize the makingcondition. Finally, the photocatalytic activity of the new photocatalyst is studied.In the paper, the Ag⁺/4A zeolite was prepared by ion exchanging and then different laterexperiments were used to change the Ag⁺ to the Ag using 4A zeolite as carrier. Thepreparation conditions of the photo-reduction method were investigated and optimized.Investigated by XRD and SEM, the photo-reduction method is the best method, not only itproduces the characteristic peak of Ag, but also it can keep the 4A zeolite as its originalstructure; when the exchanging temperature is 50℃, exchanging time is 3 h and pH valueis 7.0, the amount of Ag can be the best value.TiO₂ can be loaded on the Ag/4A zeolite by sol-gel processing using tetrabutyl titanateas a precursor. The new Ag- TiO₂／4A zeolite photocatalyst was characterized by XRD,SEM, TEM, and IR and used to study the photodegradation of methyl orange in anaqueous suspension. The characterization results show the new photocatalyst do notdestroy the structure of 4A zeolite; TiO₂ is loaded around the carrier and Ag is distributingthe surface; XRD results show that the characteristic peak of TiO₂ appeared in low heattreatment temperature. The photodegradation results show that the degradability of the newphotocatalyst is enhanced compared with the Ag/4A zeolite; the Ag-TiO₂/4A zeolite hasgood photocatalytic activities when it's in acid solution, short-wave ultraviolet, also it hasgood repeated using times.