【作者】 陈浩；

【导师】 李松；

【作者基本信息】 华中科技大学 ， 动力工程及工程热物理， 2023， 硕士

【摘要】 金属有机骨架（MOFs）具有比表面积高、孔体积大及吸附性能优异等特点,在吸附式海水淡化/制冷领域具有巨大的应用潜力,但粉末状MOFs直接应用会造成一系列的问题。在MOFs成型过程中,粘结剂的使用对其结构特征和吸附性能等存在不同影响,本文选择了稳定性高的MIL-100（Fe）,研究了适用于MIL-100（Fe）的成型方法。此外,MOFs在吸附式海水淡化/制冷复合系统中的性能鲜有报道,本文设计搭建了海水淡化/制冷复合系统,并系统探究了MIL-100（Fe）颗粒在海水淡化和制冷方面的应用潜力。选用聚乙烯醇缩丁醛（PVB）、羟乙基纤维素（HEC）、硅溶胶（SS）和蔗糖（SUC）4种粘结剂,制备了包含不同粘结剂种类和含量的MIL-100（Fe）颗粒,探究了粘结剂对MIL-100（Fe）结构特征、水蒸气吸附性能和机械强度的影响规律。结果表明,尽管粘结剂的加入会堵塞MIL-100（Fe）中部分孔道,导致MIL-100（Fe）颗粒水蒸气吸附量和比表面积出现了不同程度的降低,但颗粒都获得了一定的机械强度。其中,PVB含量为5%的MIL-100（Fe）@5PVB颗粒的比表面积（1713.1 m²/g）和水蒸气吸附量（0.485g/g）最高,且其机械强度达到42 N。为进一步探究MIL-100（Fe）@5PVB颗粒的应用前景,本文设计搭建了一套吸附式海水淡化/制冷复合系统,测试了MIL-100（Fe）@5PVB颗粒在不同工况下的比日产水量（SDWP）和比制冷功率（SCP）。研究发现,基于MIL-100（Fe）@5PVB的海水淡化/制冷复合系统最佳半循环时间(t_{half cycle})为600 s,且SDWP和SCP随冷冻水温度(T_chilled)和热水温度(T_hot)的升高呈现增加趋势,这主要是T_chilled和T_hot的升高有利于MIL-100（Fe）@5PVB颗粒对水蒸气循环吸附量的增大。同时,与传统吸附剂硅胶相比,MIL-100（Fe）@5PVB颗粒的SDWP和SCP约为硅胶的4倍。采用电感耦合等离子体质谱仪（ICP-MS）检测了系统制取淡水的水质,表明所得淡水满足生活饮用水标准。更多还原

【Abstract】 Metal-organic frameworks（MOFs）with high specific surface area,large pore volume and excellent water adsorption capacity are recognized as one of the most potential candidates for adsorption desalination/cooling.However,the direct use of MOFs in powder form will cause a series of problems.During the preparation of MOFs granules,the use of binder has different effects on their structural characteristics and adsorption performance of MOFs.In this paper,MIL-100（Fe）with high stability is selected and the shaping method applicable of MIL-100（Fe）is studied.In addition,the performance of MOFs in adsorption desalination/cooling systems has rarely been reported.In this work,a desalination/cooling system was designed and built,and the potential of MIL-100（Fe）granules in desalination and cooling was systematically explored.In this work,four binders,polyvinyl butyrate（PVB）,hydroxyethyl cellulose（HEC）,silica sol（SS）and sucrose（SUC）,were chosen to prepare MIL-100（Fe）particles containing different binder types and contents.The effects of binders on the structural characteristics,water vapor adsorption properties and mechanical strength of MIL-100（Fe）was investigated.It is found that although the presence of binder caused pore blockage of MIL-100（Fe）,resulting in reduced specific surface area and water vapor adsorption capacity,the MIL-100（Fe）granules all obtained a certain mechanical strength.MIL-100（Fe）@5PVB granules with 5%PVB loading exhibited the highest specific surface area（1713.1 m²/g）and water vapor adsorption capacity（0.485 g/g）,and its mechanical strength reached 42 N.In order to investigate the application prospects of MIL-100（Fe）@5PVB granules,an adsorption desalination/cooling system was designed and built in this paper,and the specific daily water production（SDWP）and specific cooling power（SCP）of MIL-100（Fe）@5PVB granules were tested under different working conditions.It was found that the optimal half cycle time(t_{half cycle})of the MIL-100（Fe）@5PVB-based desalination/cooling system was600 s,and the SDWP and SCP showed an increasing trend with the increase of chilled water temperature(T_chilled)and hot water temperature(T_hot),which can be ascribed to the increase of T_chilled and T_hot favored increase the cyclic adsorption capacity of water vapor by MIL-100（Fe）@5PVB granules.Compared with the conventional adsorbent silica gel,the SDWP and SCP of MIL-100（Fe）@5PVB granules were about four times higher than those of silica gel.Inductively Coupled Plasma Mass Spectrometry（ICP-MS）was used to test the quality of fresh water produced by the system,which showed that the fresh water obtained met the standard of drinking water.更多还原