金属—有机骨架膜的制备及其气体分离应用研究

发布时间：2018-06-07 17:17

本文选题：金属-有机骨架材料 + 气体分离膜　；参考：《北京化工大学》2016年博士论文

【摘要】：金属-有机骨架材料(Metal-Organic Frameworks, MOFs)是由金属离子和有机配体通过自组装过程形成的纳米多孔材料。MOF材料有诸多优点,如密度小、比表面积高、不饱和金属位点和孔尺寸可调节性等,目前已经应用在气体储存、分离、催化、吸附等领域。近几年,MOF材料的其中一个应用—气体膜分离,吸引了大批实验和理论研究学者。膜分离技术,是工业生产中从各种尾气里捕获二氧化碳的有效方法之一,它低能耗、工艺简单、无相变。在膜分离领域里,新型的膜材料研发成为了首要的问题。本文采用不同的方法制备了 MOF膜材料及其复合膜材料,并应用到气体分离领域,通过扫描电子显微镜分析、X射线衍射分析、热重分析、红外分析等方法,对合成的膜材料进行了表征,进而考察其对透过气体的分离性能。主要研究内容如下:1、采用常规原位生长法合成ZIF-9膜,并研究了偶联剂用量、金属盐与配体的物料比、反应温度、反应时间等条件对ZIF-9膜的生长和气体分离性能的影响,进而得到了最佳合成条件为:偶联剂用量为偶联剂溶液体积分数的2%,金属盐与配体的摩尔比为1:2,反应温度为110℃,反应时间为72小时。2、本文提出变温法合成ZIF-9膜的策略,采用扫描电子显微镜分析、X射线粉末衍射分析、气体分离性能测试等方法,对变温法合成的膜与原位生长法合成的膜进行比较。结果表明,采用变温法合成的ZIF-9膜,不论在膜的生长方面,还是在气体分离性能方面,都要优于原位生长法。这种变温法的优势在于:它将MOF膜合成过程的成核和生长阶段分开,达到了低温成核、高温生长的目的,实验的低温阶段选用80℃、高温阶段选用130℃。目前来看,变温法在MOF膜合成领域的使用尚属首次。3、采用层层沉积热处理的方法,将离子液体(ILs)功能化后的碳纳米管(CNTs),附着在已合成的ZIF-9膜的表面,同时,在ZIF-9膜的缺陷处,也填充了离子液体功能化后的碳纳米管,合成了CNT@IL/ZIF-9复合膜。测试结果表明,此三元体系膜的气体分离性能效果要比纯ZIF-9膜和IL/ZIF-9、CNT/ZIF-9等二元体系膜更具优势。此外,还考察了在不同的操作温度和压力下,通过此三元体系复合膜的气体分离性能的变化,得出了最佳操作条件。其稳定性、可重复性、良好的气体分离效果为膜分离领域开辟了新思路。4、成功制备了金属-有机骨架材料/嵌段聚醚酰胺(ZIF-8/PEBAX-1074)的混合基质膜。实验探究了添加不同含量的ZIF-8 (0%,5%,10%,15%,20%),并利用流涎法制备混合基质膜,在气体分离性能方面的异同。结果表明,此混合基质膜表现出了很高的CO2/H2、C02/N2、CO2/CH4分离性能。在ZIF-8添加量为15%时,混合基质膜表现出最优的气体分离性能。由于嵌段聚醚酰胺是已经工业化和商业化的聚合物,而ZIF-8的合成成本较低,操作简单,两种材料的复合对实际工业应用具有广阔的前景。5、本文将两种MOF材料:MIL-53(A1)和ZIF-9同时添加到嵌段聚醚酰胺,制备了 ZIF-9/MIL-53(Al)/PEBAX-2533混合基质膜材料。通过气体分离性能的考察可以看出,此混合基质膜对的二氧化碳有着良好的分离效果。同时,本文还研究了这种膜在气体分离效果上与ZIF-9/PEBAX-2533 和 MIL-53(Al)/PEBAX-2533 的不同,并且探讨了两种MOF材料添加量不同时,混合基质膜的分离效果的变化。该研究为工业生产中膜分离工艺提供了新思路。
[Abstract]:Metal organic framework material (Metal-Organic Frameworks, MOFs) is a nano porous material.MOF material which is formed by metal ions and organic ligands through self-assembly process. It has many advantages, such as small density, high surface area, unsaturated metal site and pore size, and so on. It has been used in gas storage, separation, catalysis, adsorption and so on. In recent years, one of the applications of MOF material, gas membrane separation, has attracted a large number of experimental and theoretical researchers. Membrane separation technology is one of the effective methods to capture carbon dioxide from all kinds of tail gas in industrial production. It has low energy consumption, simple process and no phase change. In the field of membrane separation, the research and development of new membrane materials has become the first one. In this paper, MOF film materials and their composite membrane materials were prepared by different methods and applied to the field of gas separation. Through scanning electron microscope analysis, X ray diffraction analysis, thermogravimetric analysis, infrared analysis and other methods, the synthetic membrane materials were characterized, and the separation properties of the permeable gases were investigated. The contents are as follows: 1, the ZIF-9 film is synthesized by the conventional in situ growth method. The effects of the amount of coupling agent, the material ratio of the metal salt and the ligand, the reaction temperature and the reaction time on the growth of the ZIF-9 film and the gas separation properties are studied. The optimum synthesis conditions are obtained: the amount of the coupling agent is 2% of the volume fraction of the coupling agent and the metal salt. The molar ratio of the ligand is 1:2, the reaction temperature is 110 C and the reaction time is 72 hours.2. This paper puts forward the strategy of synthesizing ZIF-9 film by the variable temperature method. The methods of scanning electron microscope analysis, X ray powder diffraction analysis and gas separation performance test are used to compare the films synthesized by the variable temperature method and in situ growth method. The results show that the method is used. The ZIF-9 films synthesized by the method of temperature change are better than in situ growth in both the growth of the membrane and the gas separation performance. The advantage of this method is that it separates the nucleation and growth stages of the MOF membrane synthesis process, reaching the target of low temperature nucleation and high temperature growth, the low temperature stage of the experiment is 80 C, and the high temperature stage is selected to choose 1. At present, at present, the use of temperature changing method in the field of MOF film synthesis is still the first.3. By layer deposition heat treatment, the functionalized carbon nanotube (CNTs) after the ionic liquid (ILs) is attached to the surface of the synthesized ZIF-9 film. At the same time, the carbon nanotubes are filled with the functionalized ionic liquids at the defects of the ZIF-9 film, and the CNT@ has been synthesized. The test results show that the gas separation performance of the three element system film is more advantageous than the pure ZIF-9 film and the two element system membrane such as IL/ZIF-9, CNT/ZIF-9 and so on. In addition, the optimum operating conditions are obtained by the change of gas separation performance through the three element composite membrane under different operating temperatures and pressures. The stability, repeatability, and good gas separation effect opened a new idea for the membrane separation field.4. The mixed matrix membrane of metal organic framework material / block polyether amide (ZIF-8/PEBAX-1074) was successfully prepared. The experiment was carried out to investigate the addition of different content of ZIF-8 (0%, 5%, 10%, 15%, 20%), and the mixed matrix membrane was prepared by the salivation method. The results show that the mixed matrix film shows a high separation performance of CO2/H2, C02/N2 and CO2/CH4. When the amount of ZIF-8 is 15%, the mixed matrix film shows the best gas separation performance. As the block polyether amide is a commercialized and commercialized polymer, the synthesis cost of ZIF-8 is low and the operation is simple. The combination of the two materials has a broad prospect for practical industrial applications. In this paper, two kinds of MOF materials, MIL-53 (A1) and ZIF-9 are added to the block polyether amides, and the ZIF-9/MIL-53 (Al) /PEBAX-2533 mixed matrix material is prepared. Through the investigation of gas separation performance, it can be seen that this mixed matrix has good carbon dioxide for the carbon dioxide. At the same time, this paper also studied the difference between ZIF-9/PEBAX-2533 and MIL-53 (Al) /PEBAX-2533 in the gas separation effect, and discussed the change of the separation effect of the mixed matrix membrane of the two kinds of MOF materials, which provided a new idea for the membrane separation process in the industrial production.
【学位授予单位】：北京化工大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TQ051.893

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