Preparation And Photocatalytic Activity Of Modified Nanoparticle Titanium Dioxide Loaded On Zeolite

ABSTRACT:Pure titania and nanoparticle titania doped with different amount of Zinc,Cuprum,Lanthanum and Lanthanum and Zinc co-doped TiO2nanoparticles were synthesized via sol-gel method. TiO2and Lanthanum-Zinc co-doped TiO2nanoparticles were dispersed onto the external surface of MCM-41Zeolite using a sol-gel process in order to improve the photocatalytic activity. The activities of TiO2/MCM-41and La-Zn/TiO2/MCM-41catalysts were evaluated by the ability of degradation to methyl orange and formaldehyde under UV-light. The results are as followings:(1) Metal doping TiO2nanoparticles were synthesized by sol-gel method.It was showed that modifications of Zinc,Cuprum could promoting phase transformation from anatase phase to rutile. On the contrary,modification of Lanthanum could restraining phase transformati-on. All these doping of Zinc,Cuprum and Lanthanum restrained the growth of grains and promoted the forming of nanoparticles.The optimal doping amount were judged by the ability of degradation to methyl orange.It was showed that both optimal doped amount of Zinc and Lanthanum were0.15%,and the degradation rate was89%and90%in two hours.The optimal doped amount of Cuprum was0.2%,and the degradation rate was82%in two hours. The optimal co-doped amount of Lanthanum and Zinc was0.1%Lanthanum and0.05%Zinc,and the degradation rate was95%in two hours.(2)The amount of static adsorption of3A,5A,13X,MCM-41zeolites to formaldehyde was investigated by desiccators method.It is showed that MCM-41mesoporous molecular sieve presented the best property of formaldehyde adsorption because of its large specific surface area and big channel diameter.Different amount of pure titania and0.1%Lanthanum-0.05%Zinc co-doped TiO2nanoparticles were dispersed onto the surface of MCM-41molecular sieve via sol-gel method. It is showed that MCM-41molecular sieve can restrained the growth of nanoparticles and the pore volume and diameter of MCM-41molecular sieve decreasing when doping amount increasing. The optimal amount of doped TiO2or La-Zn/TiO2was40%, and the degradation rate was86%and96%in80minutes.(3)The four products were pure TiO2, La-Zn/TiO2,MCM-41molecular sieve and40%La-Zn/TiO2/MCM-41,and the article investigated the property of adsorption and degradation of the four products to formaldehyde.40%La-Zn/TiO2/MCM-41showed the best adsorbent and photocatalytic activities, and the degradation rate was95%in80minutes.