摘要
以钛酸四丁酯为前驱体,硅藻土为载体,采用溶胶-凝胶法制备TiO_2/硅藻土负载型光催化剂。以硝酸镧为镧源,采用等体积浸渍-焙烧法制备La^(3+)/TiO_2硅藻土光催化剂。通过XRD和SEM对制备的催化剂进行表征,以亚甲基蓝溶液模拟有机废水,考察n(Ti)∶n(Si)及La3+掺杂量对催化剂光催化性能的影响,结果表明,硅藻土可提高TiO_2分散性,降低TiO_2晶粒尺寸,并抑制其由锐钛矿相向金红石相的转变。在n(Ti)∶n(Si)=1∶1、焙烧温度550℃和La3+掺杂质量分数1%条件下,La^(3+)/TiO_2硅藻土光催化剂的光催化活性较好,紫外光连续照射180 min,亚甲基蓝降解率可达99.9%。
Using tetrabutyl titanate as the precursor and diatomite as the carrier, TiOJdiatomite photocat- alysts were prepared by sol-gel method, and then La3＋/TiO2-diatomite photocatalysts were synthesized by using lanthanum nitrate as lanthanum source and the impregnation-calcination method. The as-prepared catalysts were characterized by X-ray powder diffraction and scanning electron microscope. Using methyl- ene blue as simulated organic wastewater, the effects of Ti/Si molar ratios and La3＋ doping amounts on photocatalytic performance of the photocatalysts were studied. The results showed that the diatomite could improve the dispersity of TiO2 and reduce the crystal size of TiO2. In addition, the transformation of ana- tase-to-rutile phase could be restrained when diatomite was doped into TiO2. Under the condition of n（Ti）：n（Si） = 1： 1, La3＋ doping mass fraction 1%, and calcination temperature 550 ℃, La3＋/TiO2- diatomite photocatalyst exhibited the best photocatalytic activity. The degradation rate of methylene blue reached 99.9% under the continuous irradiation of UV light for 180 min.
出处
《工业催化》
CAS
2016年第8期38-42,共5页
Industrial Catalysis
