金属有机骨架材料UiO-66的制备及其对溶液中NO_3~-的吸附

采用溶剂热法合成了金属有机骨架材料UiO-66。通过XRD、SEM、FTIR对其进行了表征。考察了UiO-66对溶液中NO_3~-的吸附性能。实验结果表明,加入冰乙酸作调节剂后,得到的UiO-66晶体形貌均匀,直径在100nm左右,结晶度更好。在初始溶液pH为5、反应温度为30℃的条件下,UiO-66吸附NO_3~-反应90 min后,吸附达到平衡,平衡吸附量为39.67 mg/g。UiO-66吸附NO_3~-的吸附行为符合Freundlich等温线和准二级动力学吸附模型。吸附作用主要是材料中金属位点Zr对NO_3~-的静电吸附。UiO-66材料具有良好的再生性能,可重复使用。

Preparation of metal-organic framework UiO-66 and adsorption of NO3- from aqueous solution

The metal-organic framework UiO-66 was prepared by solvothermal method and the structure was characterized by XRD,SEM,FTIR. Its adsorption capability to NO₃^- in solution was studied. The experimental results showed that when using glacial acetic acid as regulator,the UiO-66 crystal had uniform morphology and better crystallinity with about 100 nm of diameter. Under the conditions of pH 5 and reaction temperature 30 ℃,the adsorption reached equilibrium after 90 min and the equilibrium adsorption capacity was 39.67 mg/g. The adsorption process followed Freundlich isotherm and the pseudo second-order model. The main adsorption mechanism was electrostatic adsorption of metal sites Zr to NO₃^-. UiO-66 had good regenerability and could be reused.