以铁镁复合草酸盐为前驱体制备了介孔铁镁复合氧化物材料,采用扫描电子显微镜、透射电镜、孔隙化学吸附分析仪等对产物进行了表征。将介孔铁镁复合氧化物应用于水体中Cr(Ⅵ)的吸附,考察了吸附条件对其去除Cr(Ⅵ)效果的影响,探讨了吸附的热力学和动力学规律。结果表明:获得的铁镁复合氧化物为纳米晶构筑的介孔材料,比表面最高达157.25m2/g常温下,在pH值为2时能有效吸附Cr(Ⅵ),其吸附等温线符合Langmuir吸附模型t饱和吸附容量为30.67mg/g;吸附动力学符合Lagergren二级速率方程,吸附过程为吸热自发的物理过程。
Mesoporous Fe--Mg composite oxide was synthesized via decomposition of the corresponding oxalate precursor. The products were characterized by scanning electron microscope, transmission electron microscope, and N2 adsorption. The adsorption property of Cr(VI) onto the mesoporous Fe-Mg composite oxides was investigated. The thermodynamics and dynamics for the adsorption of Cr(VI) onto Fe-Mg composite oxide were discussed. The results show that the specific surface area of the mesoporous Fe-Mg composite oxide constructed by nanocrystalline is 157.25 m2/g. The chromium(VI) can be effectively removed from aqueous solution at pH 2.0. The adsorption isotherm behavior followed the Langmuir equation, and the maximal static adsorption capacity is 30.67 mg/g. The adsorption kinetics followes a Lagergren pseudo-second-order model. The adsorption process is an endothermic and spontaneous physical process.