Fe_3O_4纳米颗粒的制备及其净化含油污水的研究

Preparation of Fe_3O_4 nanoparticles and their purification of oil-bearing wastewater

采用沉淀法在碱性条件下不使用任何表面活性剂直接制备出Fe3O4纳米颗粒。用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、XRD粉末衍射仪、振动样品磁强计及激光粒度分析仪对制备的纳米颗粒性质进行了表征。结果显示所制得的Fe3O4颗粒单颗平均粒径约为9 nm,具有超顺磁性,晶型单一,比饱和磁化强度为53.279 emu/g,在水中分散后粒度集中分布在10—26 nm和114—150 nm这2个区域。将其应用于油田污水处理,并与粒度分布在0.5—1.0μm的市售Fe3O4粉末以及活性炭粉末的除油效果进行了对比,研究了3种粉末不同质量分数与净化效果的关系以及磁性纳米颗粒净化油田污水的机理。

Fe3O4 nanoparticles were prepared by precipitation based on alkaline conditions without any sttrfactants. The characterization of Fe3O4 nanoparticles was carried out by the methods of Scanning Electron Microscopy, Transmission Electron Microscopy, X-ray Diffraction, Vibrating Sample Magnetometer, and laser particle sizer. The result shows that the synthesized Fe3O4 nanoparticles with the average diameter of 9 nm exhibit superparamagnetic behavior and single crystalline. The nanoparficles have saturation magnetization of 53.279 emu/g and two different size distribution ranges of 10-26 nm and 114-150 nm when dispersed in water. Then they were used for oilfield waste water treatment, while compared with the market Fe3O4 whose particle size distribution is 0. 5-1.0μm and the purifying effect of activated carbon powders. The relationship between different mass fraction and purifying effect of these three powders, as well as the mechanism of magnetic nanoparticles purification for oilfield waste water were studied.