Fe_3O_4@TiO_2复合材料对砷及染料的去除机理

THE MECHANISM OF REMOVING ARSENIC AND DYE BY Fe_3O_4@TiO_2 COMPOSITE

利用溶剂热法制备了具有不同TiO_2外壳厚度的Fe_3O_4@TiO_2复合纳米材料,并探究其对砷及染料的去除机理。通过材料表征发现:Fe_3O_4@TiO_2复合材料为典型的核壳结构,Fe_3O_4与TiO_2通过化学反应结合形成Ti^(3+),材料感光范围展宽>600 nm;通过吸附等温线实验,n(TiO_2)∶n(Fe_3O_4)为0. 5时,Fe_3O_4@TiO_2复合材料对砷有较好的吸附效果(30 mg/g);可见光下,Fe_3O_4@TiO_2复合材料对染料甲基橙具有高效的光催化效率。Fe_3O_4@TiO_2复合材料是一种既可去除砷又可光催化降解染料的多功能材料,在环境污染治理方面将有广阔的应用前景。

The development of multifunctional composites provides an effective way to solve environmental problems.Fe3O4@TiO2 composite nano-material with the different optimized TiO2 shell thickness was synthesized by solvothermal method.Its removal mechanism for arsenic and dye was explored.The morphology and compositional characterization results showed that the Fe3O4@TiO2 magnetic composite had typical core-shell structure.Fe3O4 and TiO2 were chemically combined into Ti^3+, further extending photosensitive range (>600 nm).Based on an adsorption isotherm experiment, when the molar ratio of Fe3O4 and TiO2 was 0.5, Fe3O4@TiO2 composite exhibited better adsorption efficiency for arsenic (30 mg/g).The Fe3O4@TiO2 composite presented high photocatalytic efficiency for methyl orange (MO) which acts as a dye under visible light.The Fe3O4@TiO2 composite is a multifunctional material that can not only remove arsenic, but also degrade dyes by photocatalysis, thus having a huge application prospect in treatment for arsenic and dyeing wastewater.