金属(Fe, Zn)-有机骨架的制备及对孔雀石绿吸附性能研究

Preparation of metal(Fe,Zn)-organic framework and its adsorption performance for malachite green

采用水热合成法和室温搅拌法分别制备MIL-88(Fe)和ZIF-8两种MOFs材料,利用SEM、XRD、BET和FIIR等表征手段对两种材料进行结构与性能的分析。结果表明,成功制备出结晶度较高的两种MOFs材料,MIL-88(Fe)呈纺锤状,晶粒大小为350~550 nm,其闭孔比表面积为176 m^(2)/g;ZIF-8为正十二面体,晶粒平均尺寸在50 nm左右,比表面积为416 m^(2)/g。以这两种材料为吸附剂,对孔雀石绿染料进行吸附性能研究。结果表明,两种材料在时间为180 min左右达到吸附平衡,吸附曲线均符合准一级动力学模型,MIL-88(Fe)和ZIF-8对50 mg/L的孔雀石绿溶液最大吸附率分别为43.18%和34.25%,经过4次吸附循环之后,两种MOFs材料对孔雀石绿的脱色率仍可达到90%以上,表明两种MOFs材料具有良好的吸附性能和优异的循环稳定性,在染料废水处理方面有广阔的发展前景。

MIL-88(Fe) and ZIF-8 were prepared by hydrothermal synthesis method and stirring at room temperature,respectively.The structures and properties of the two materials were analyzed by SEM,XRD,BET and FIIR.The results showed that MIL-88(Fe) and ZIF-8 with good crystallinity were successfully prepared.MIL-88(Fe) exhibited a spindle-like appearance,with a size of about 350~550 nm and a specific surface area of 176 m^(2)/g;ZIF-8 showed a regular dodecahedron with an average size of about 50 nm and a specific surface area of 416 m^(2)/g.The adsorption properties of malachite green were studied using these two materials as adsorbents.It can be observed that the adsorption equilibrium of the two materials was achieved at about 180 min,and the adsorption curves were in line with the quasi-first-order kinetic model.The maximum adsorption rate of MIL-88(Fe) and ZIF-8 for 50 mg/L malachite green solution were 43.18% and 34.25%,respectively.After four adsorption cycles,the decolorization rate of malachite green by the two MOFs could still reach more than 90%,indicating that the two MOFs possess good adsorption performance and excellent cycle stability,and have broad development prospects in dye wastewater treatment.