nvestigation of Synthesis Conditions of MOF-5 Crystals and Related MOF-5/α-Al2O3 Membranes

• Main Authors: Wang-Hui Wu, 吳旺輝
• Other Authors: Bor-Kae Chang
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/25y394

碩士 === 國立中央大學 === 化學工程與材料工程學系 === 104 === Metal-organic frameworks (MOFs) are porous crystalline materials consisting of metal ions linked together by organic bridging ligands. Because of their outstanding properties, MOFs are used in a variety of promising applications in the fields of adsorption, drug delivery, catalysis, membranes, etc. With its special structure, functional groups, high surface area, and exceptional pore volume, one of the main applications of such material is hydrogen storage and CO2 separation. In industry, membranes, including novel membranes utilizing MOFs, are often used extensively to perform gas separation. Currently in literature, MOF-5, which is the most representative MOF, has been successfully synthesized on membrane via secondary growth on substrates such as porous α-alumina. In this work, MOF-5 crystals and related MOF-5/α-Al2O3 membranes were synthesized to systematically investigate the various reaction conditions. MOF-5 crystals were successfully formed at 130℃ and 21 hours via solvothermal synthesis. In order to understand the impact of reaction time, temperature and metal-to-ligand ratio on synthesizing MOF-5, several synthesis conditions were investigated. Then, synthesis of MOF-5 membranes with different temperature were also investigated. MOF-5 crystals and related MOF-5/α-Al2O3 membranes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR）. The results of the XRD pattern showed the presence of another crystal called MOF-69c. This suggests that before pure MOF-5 can be formed, MOF-69c and intermediate phases were synthesized first. Successfully changing for the first time the synthesis temperature to 120℃, it was found that MOF-5 crystals were formed, but with the intermediate phases present. As a result of this study, the reaction time, temperature, and metal-to-ligand ratio have been found to have a vital influence on forming MOF-5. We have laid the foundation for finding the best synthesis parameters to synthesize MOF-5 on porous α-alumina. Future work will include gas permeation of various gases, both single and binary components on membrane samples using a homemade permeation setup.