机械化学法合成金属有机骨架材料HKUST-1及其吸附苯性能

金属有机骨架材料是一类新兴纳米多孔功能材料,研究出一种绿色环保的制备和活化金属有机骨架材料方法对于其工业应用具有重要的意义。应用机械化学法合成金属有机骨架材料(HKUST-1),并提出采用乙醇对所合成的材料进行活化和纯化,讨论不同溶剂(氯仿、乙醇)活化对合成的HKUST-1的孔隙结构和吸附性能的影响。研究结果表明:相对于传统水热法合成时间(24 h),无溶剂机械化学法反应时间缩短为30 min;活化溶剂对HKUST-1的比表面积和孔结构有较大的影响,乙醇比氯仿更容易置换出HKUST-1孔道中残留的前驱物,增大材料的比表面积,乙醇活化得到的HKUST-1比表面积高达1442.7 m²·g^-1。在298 K、8 kPa条件下,乙醇活化得到的HKUST-1对苯的吸附容量高达6.90 mmol·g^-1,比氯仿活化和水热法合成的HKUST-1对苯的吸附量高约25%,而且高于同等温度压力条件下活性炭、碳分子筛、沸石等常规吸附剂对苯的平衡吸附量。

Mechano-chemical synthesis of HKUST-1 with high capacity of benzene adsorption

Metal-organic frameworks (MOFs) are a new class of nanoporous materials. An efficient and environmentally friendly method for the synthesis of MOFs is needed for efficient industrial applications. In this work, a porous metal-organic framework HKUST-1 was prepared by the mechano-chemical method. The effects of different activation solvents (chloroform and ethanol) on the surface area, pore structure and benzene adsorption of HKUST-1 were investigated. The mechano-chemical synthesis time of HKUST-1 could be reduced from 24 h to 30 min compared with the hydrothermal method. The surface area and pore volume of HKUST-1 were significantly affected by activation solvents. Using ethanol as an activation solvent could more easily displace the precursors remaining in the channels of HKUST-1, thus achieving a larger surface area (1442.7 m²·g^-1) and 25% higher benzene adsorption (6.90 mmol·g^-1 at 298 K and 8 kPa). Under the same condition, the benzene absorption capacity of the HKUST-1 sample was higher than the regular absorbents, such as activated carbon, molecular sieve and zeolite.