磁性介孔锰铁复合氧化物对Cr(Ⅵ)的吸附性能研究

Adsorption characterization of Cr(Ⅵ) on magantic mesoporous manganese-iron oxide

以复合金属草酸盐为前驱体制备了纳米晶构筑的介孔锰铁氧化物材料,采用透射电镜、X射线衍射仪和固体比表面测定仪等对产物进行了表征.并研究了其对水体Cr(Ⅵ)的吸附性能,考察了pH及离子强度对吸附容量的影响、吸附动力学、吸附等温线以及碱液对Cr(Ⅵ)的洗脱率。结果表明,获得的锰铁氧化物为纳米晶构筑的介孔材料,比表面达277.4 m2/g,对Cr(Ⅵ)在酸性条件下有较强的吸附性能。在初始Cr(Ⅵ)质量浓度为100 mg/L,pH值在2时,10 min内能使溶液中的Cr(Ⅵ)去除率达96.8%,最大Cr(Ⅵ)吸附容量Qm为40 mg/g。

Mesoporous manganese-iron oxide constructed by nanoparticles was synthesized by the decomposition of corresponding oxalate precursor.The products were characterized by TEM,XRD and N2 adsorption.The adsorption property of Cr（Ⅵ） on maganetic mesoporous manganese-iron oxide was also investigated.The effects of pH and ion strength on adsorption capacity,the adsorption kinetics,adsorption isotherm and the desorption of Cr（Ⅵ） from manganese oxide were discussed in detail.The results show that the surface area of mesoporous manganese iron oxide constructed by nanocrystlline was 277.4 m2/g,and the adsorption capacity became bigger with the increase of solution acidity.96.8% of the Cr（Ⅵ） content can be removed when the Cr（Ⅵ） concentration was 100 mg/L in solution at pH 2.The maximal adsorption capacity was 40 mg/g.