【摘要】 以Fe3O4为核、α-Fe2O3为壳层,制备出1种核壳结构的Fe3O4/α-Fe2O3负载型纳米复合材料,采用扫描电子显微镜(SEM)、透射电镜(TEM)和X射线衍射仪(XRD)等表征手段对核壳材料的形貌、组成及结构等进行了表征,并考察了该材料对Cr(Ⅲ)的去除性能以及Fe3O4/α-Fe2O3粒子的再生和重复利用性能。结果表明,制备得到的Fe3O4/α-Fe2O3纳米粒子具有典型的核壳结构,粒径约为40~100 nm。在p H为4.5时,Fe3O4/α-Fe2O3对Cr(Ⅲ)的饱和吸附量达到33.34 mg/g。Freundlich方程比Langmuir方程更好地描述了Fe3O4/α-Fe2O3吸附Cr(Ⅲ)的行为,表明此吸附是多层物理吸附。以0.1 mol/L的H2SO4为解吸剂将吸附在核壳Fe3O4/α-Fe2O3上的Cr(Ⅲ)解吸,可以实现很好的再生,再生的Fe3O4/α-Fe2O3经过3次循环使用后,对Cr(Ⅲ)仍具有较好的去除能力。更多还原

【Abstract】 A magnetic core-shell Fe3O4/α-Fe2O3 material was synthesized by utilizing Fe3O4 as the cell and α-Fe2O3 as the shell. The morphology, component and structure of the material were characterized by TEM, SEM and XRD. The performance of removing chromium(Ⅲ) and the regeneration and reuse of Fe3O4/α-Fe2O3 particles were carefully studied. The results indicated that the prepared spherical Fe3O4/α-Fe2O3 samples had core-shell structure and show the particle size ranged from 40 to 100 nm. The adsorption capacity of Cr(Ⅲ) by Fe3O4/α-Fe2O3 was determined to be 33.34 mg/g when the p H was4.5. The Cr(Ⅲ) absorption behavior by magnetic Fe3O4/α-Fe2O3 nanoparticles could be described by Freundlich isotherm model better than Langmuir isotherm model, indicating that it was multimolecular layer physical adsorption. The Cr(Ⅲ) absorbed on the core-shell Fe3O4/α-Fe2O3 nanoparticles could be desorbed by 0.1 mol/L H2SO4. Moreover, the regenerated adsorbent still exhibited good Cr(Ⅲ) removal efficiency after being reused circularly for three times.更多还原