MIL型金属有机框架材料空气除湿性能研究

Air Dehumidification Performance of MIL-type Metal-organic Frameworks

固体除湿装置因其结构简单、可利用低品位能源等优点,在空气调节及空气取水中发挥重要作用。除湿材料是固体除湿装置的关键部分,关乎整个设备的效率和能耗。采用水热法合成了MIL-101(Cr)、MIL-101(Fe)和MIL-100(Fe),通过X射线衍射对其进行了表征。搭建了固定床吸附/脱附实验台,测定了水蒸气在3种除湿材料上的吸附等温线和吸附动力学特性。对比研究了MIL-101(Cr)、MIL-101(Fe)和MIL-100(Fe)3种金属有机框架化合物对水蒸气的吸附性能。结果表明:MIL-101(Cr)和MIL-101(Fe)对水蒸气具有超高吸附能力,分别高达1.50 g/g和1.33 g/g。MIL-101(Fe)吸附速率最快,吸附穿透时间最短,并且吸附速率随相对湿度的增大而减小。相对湿度50%时,MIL-101(Fe)吸附速率达到了0.738。10次循环后MIL-101(Cr)和MIL-101(Fe)的吸附容量的损失分别为3.33%和3.22%,循环吸附表明MIL-101(Cr)和MIL-101(Fe)对水蒸气吸附具有优异的可逆性和稳定性。

Solid dehumidification device plays an important role in air conditioning and air water intake because of its simple structure and low-grade energy.Dehumidifying material is the key part of solid dehumidification device,which is related to the efficiency and energy consumption of the whole equipment.MIL-101(Cr),MIL-101(Fe)and MIL-100(Fe)were synthesized by hydrothermal method and characterized by X-ray diffraction.A fixed-bed adsorption/desorption experiment platform was set up to determine the adsorption isotherms and adsorption kinetic characteristics of water vapor on three dehumidification materials.The water vapor adsorption properties of MIL-101(Cr),MIL-101(Fe)and MIL-100(Fe)metal-organic frameworks were compared.The experimental results show that MIL-101(Cr)and MIL-101(Fe)have super high adsorption capacity for water vapor,up to 1.50 g/g and 1.33 g/g,respectively.MIL-101(Fe)has the fastest adsorption rate and the shortest breakthrough time,and the adsorption rate decreases with the increase of relative humidity.The adsorption rate of MIL-101(Fe)reached 0.738 at 50%relative humidity.After 10 cycles,the loss of adsorption capacity of MIL-101(Cr)and MIL-101(Fe)is 3.33%and 3.22%,respectively.Cyclic adsorption shows that MIL-101(Cr)and MIL-101(Fe)had excellent reversibility and stability for water vapor adsorption.