球磨法制备Y^(3+)/TiO_2光催化剂及处理海水养殖废水  

Y^(3+)/TiO_2 Photocatalysts: Preparation via Ball Milling Method and Marine Aquaculture Wastewater Treatment

作　　者：李晨[1] 吴迪[1] 张大帅[1] 王丽丽 张小朋[1,2] 刘建[3] 张苏敏 李天略[1] 史载锋[1] 林强[1] LI Chen;WU Di;ZHANG Da-Shuai;WANG Li-Li;ZHANG Xiao-Peng;LIU Jian;ZHANG Su-Min;LI Tian-Lue;SHI Zai-Feng;LIN Qiang(Key Laboratory of Water Pollution Treatment & Resource Reuse, Hainan Normal University, Haikou 571127, China;State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, Nanjing 210023, China;College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China)

机构地区：[1]海南省水环境污染治理与资源化重点实验室海南师范大学化学与化工学院,海口571127 [2]污染控制与资源化研究国家重点实验室南京大学环境学院,南京210023 [3]南京林业大学化学工程学院,南京210037

出　　处：《无机化学学报》2019年第3期376-384,共9页Chinese Journal of Inorganic Chemistry

基　　金：海南省重点研发项目(No.ZDYF2017011);海南省重大科技计划项目(No.ZDKJ2016022;ZDKJ2016022-02);海南省自然科学基金(No.20156242;2017100;217101;20152033);污染控制与资源化研究国家重点实验室开放基金(No.PCRRF17026)资助

摘　　要：采用机械球磨法制备Y^(3+)修饰TiO_2光催化剂,利用紫外-可见漫反射光谱(UV-Vis DRS)、X射线光电子能谱(XPS)、X射线粉末衍射(XRD)、扫描电镜(SEM)等对其进行表征,在紫外光下,以亚甲基蓝(MB)为去除物来考察催化剂活性并优化球磨工艺。将最佳条件下制得的Y^(3+)/TiO_2光催化剂负载于不同半径的塑料浮球上,分别在紫外光和模拟太阳光照射下处理海水养虾废水,通过CODCr(chemical oxygen demand)及三维荧光观察有机物含量变化。结果表明,当Y^(3+)的物质的量分数为2%,球磨时间4 h,球料质量比4∶1,转速为500 r·min^(-1)时,MB光催化降解反应速率常数可达0.111 3 min^(-1),是纯TiO 2的4.2倍。由UV-Vis DRS、XPS、N_2吸附-脱附、XRD、SEM等表征结果显示,2%Y^(3+)/TiO_2样品的禁带宽度降低至3.05 eV,光吸收发生红移,并产生可见光响应,表面吸附氧含量明显增加,比表面积增大到104 m^2·g^(-1)。采用纯TiO_2及2%Y^(3+)/TiO_2为光催化剂处理养虾废水,在可见光和紫外光下CODCr的去除率分别为14.7%和18.8%、26.9%和37.5%。考察3种直径分别为1、2、3 cm负载Y^(3+)/TiO_2浮球的光催化效果,显示直径为2 cm浮球效果最佳,CODCr去除率可达38.5%。Y3^+ modified TiO2 photocatalysts were prepared by ball milling method. The structures and properties of the photocatalysts were characterized by UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic activities were evaluated by the degradation of methylene blue (MB) aqueous solution under UV light, and the ball milling processes were optimized. Then Y3+/TiO2 photocatalysts prepared at the best conditions were coated on the plastic balls with different diameters. These balls were applied to treat shrimp wastewater under UV and visible light and CODCr (chemical oxygen demand) and 3D fluorescence spectroscopy were detected during the photocatalytic experiments. The results showed that when the molar ratio of Y3+ was 2%, milling time was 4 h, ball-to-powder weight ratio was 4∶1 and milling rate was 500 r·min-1, the reaction rate constant of MB degradation can reach up to 0.111 3 min-1 which was 4.2 times as fast as pure TiO2. From the UV-Vis DRS, XPS, N2 absorption-desorption, XRD, SEM results, the band gap of 2%Y3+/TiO2 decreased to 3.05 eV. All Y3+/TiO2 samples showed a redshift of absorption compared to pure TiO2 and it led to visible light absorption response. The content of surface oxygen vacancy had a significant increase and the BET specific area increased to 104 m2 g-1. Pure TiO2 and 2%Y3+/TiO2 were used as photocatalysts to treat shrimp wastewater, CODCr removal rates were 14.7% and 18.8% under visible light, respectively. Moreover, CODCr removal rates were 26.9% and 37.5% under UV light, respectively. The photocatalytic efficiencies of three types of plastic ball with diameters of 1, 2 and 3 cm were investigated. The results showed that the performance of 2 cm balls was best and CODCr removal rate was 38.5%.

关 键 词：球磨法 稀土Y修饰 紫外光照射 可见光照射 光催化降解 

分 类 号：O643[理学—物理化学]