铁铈共掺TiO_2/复合白土光催化剂的合成及工业废水处理活性

Preparation of Fe-Ce-codoping/Active Bleaching Clay Composite Photocatalyst and Its Photocatalytic Property in Factory Wastewater

以钛酸四正丁酯为原料,采用溶胶-微波法(Sol-microwave method)合成了铁和铈共掺型纳米TiO2粉体(Fe-Ce-TiO2),借助XRD、XPS和UV-vis等测试手段对其进行了表征,并以甲基橙为模型污染物考察了掺杂量对样品光催化活性的影响规律。XRD分析表明,所得粉体均为锐钛矿相纳米TiO2,且过渡金属铁和元素稀土铈掺杂后纳米TiO2特征衍射峰宽化,强度降低;XPS分析表明,镧和铈掺杂后样品表面存在大量的氧缺位;UV-vis吸收光谱表明,所得粉体在400nm以下均有连续宽化的吸收带,且Fe和Ce掺杂后样品对光的吸收显著增强,这是由于Ce(Ⅳ)f→d跃迁和Ce(Ⅳ)-O荷移跃迁所致;光催化实验表明,Fe和Ce共掺杂能显著提高纳米TiO2的光催化活性,其中当Fe(Ⅲ)和Ce(Ⅳ)掺杂量分别为0.1%和0.04%时,纳米TiO2光催化剂具有较高的催化活性,自然光照下光催化氧化处理卷烟厂蒸叶车间废水,效果较好,废水COD去除率达到89.8%。且催化剂易沉降分离、重复使用性能稳定。

Fe-Ce codoping nano-TiO2 catalyst was synthesized by microwave-assisted sol process.XRD,XPS and UV-vis absorption spectroscopy techniques were applied to investigate spectrum properties of Fe-Ce codoping TiO2 nanoparticles. All of the as-synthesized samples were indicated to be pure anatase phase nano-TiO2 under XRD measurement and its＇ diffraction peak broadened obviously after Fe and Ce doping. Results of XPS analysis revealed that many oxygen vacancies were produced in the surface of TiO2 nanoparticles after Fe and Ce codoping. UV-vis absorption spectra demonstrated that the as-synthesized samples had strong and wide absorption band between 200 to 400 nm and the absorption intensity increased after Fe and Ce doping.Photocatalytic experiment results showed that titanium dioxide＇s photocatalytic activity increased obviously after Fe and Ce codoping.When the doping amount of Fe and Ce was 0.2% and 0.04% respectively,the as-synthesized sample exhibited high photocatalytic activity-COD removal of cigarette factory wastewater was 89.8% and composite catalyst could be easily recovered for circulation use.