【作者】 任蕾；

【导师】 窦涛；

【作者基本信息】 太原理工大学 ， 高分子化学与物理， 2009， 硕士

【摘要】 金属有机骨架材料（MOFs,也称为金属有机分子筛）是一种类似沸石分子筛的轻质材料,其具有自组装的活性中心、较大的比表面积和孔隙率及其结构的可调控性、高渗透性等特性,可满足催化、分离、能量储藏与释放的需要。目前关于这一材料的催化性能研究正处于探索阶段,相关报道还较少。本文选择了多种金属有机骨架材料——Cu₃（BTC）₂、ZIF-68、ZIF-60、ZIF-61、ZIF-62为催化剂或载体,多种金属为活性组分,制备了系列的负载型MOFs材料,采用XRD、N₂吸附、ICP和SEM等手段对制备的材料进行了表征,并系统地研究了所制备材料的催化性能。1)Cu₃（BTC）₂的制备、表征及催化性能在不同的温度下制备了Cu₃（BTC）₂,考察其对苯甲醇氧化反应的催化性能,结果表明合成温度对Cu₃（BTC）₂的催化氧化性能有很大的影响。低温有利于抑制活性Cu²⁺中心的还原,也正是由于这些活性Cu²⁺中心的存在,使得低温下合成的Cu₃（BTC）₂（383K）在苯甲醇氧化反应中表现出高于高温条件下合成的Cu₃（BTC）₂（423K）的催化特性。所以选择低温下制备的Cu₃（BTC）₂（383K）做催化剂及催化剂载体,并制备了多种活性金属M/Cu₃（BTC）₂材料。低温下制备的Cu₃（BTC）₂能有效地催化苯甲醇氧化反应,在相同的反应条件下其活性远高于Cu/Y,且其催化活性与反应温度、反应时间、反应溶剂、催化剂的制备温度等因素有密切的关系。经反应后的Cu₃（BTC）₂催化剂虽形貌、结构等发生了一定变化但仍然能保持其原有的催化活性,甚至高于第一次使用时的催化活性,可回收和重复利用。2)M/Cu₃（BTC）₂的制备、表征及催化性能（M= Cr、Pd、Mn and Co）制备了不同的M/Cu₃（BTC）₂催化剂,考察其对苯甲醇氧化反应的催化性能,结果表明金属元素的性质对M/Cu₃（BTC）₂催化剂的催化性能有很大影响。选择Cr为活性组分,以Cu₃（BTC）₂为载体制备的催化剂,其催化氧化活性好于选择Co、Mn、Pd用相同载体制得的样品,而Pd/ Cu₃（BTC）₂的催化活性最弱。3) Pd/ ZIF-68的制备、表征及催化性能选择加氢反应常用的活性金属钯作为活性组分,以及结构稳定的ZIF-68作为载体,制备负载型催化剂Pd/ZIF-68,测试其对苯乙烯加氢反应的催化性能。实验结果表明,Pd/ ZIF-68能有效的催化苯乙烯加氢反应:a金属钯的负载量影响着催化剂的催化性能,随着金属钯负载量的增加,催化加氢的反应活性随之增加;b反应压力、反应温度、反应时间同时影响着催化剂的催化活性;c选择喹啉、噻吩作为毒性原料,选择Pd/ ZIF-68作为催化剂,测试Pd/ ZIF-68在苯乙烯加氢反应中的抗氮、抗硫性能。结果表明,骨架中含有大量氮元素的ZIF-68,有较好的抗氮性能。4)Pd/ZIFs的制备、表征及催化性能（ZIFs = ZIF-68、ZIF-60、ZIF-61、ZIF-62）选择活性金属钯,以及不同的咪唑类金属有机骨架材料作为载体,制备了Pd/ ZIF-68、Pd/ZIF-60、Pd/ZIF-61、Pd/ZIF-62,考察其对苯乙烯加氢反应的催化性能。实验结果表明催化剂的活性与载体的结构和化学组成有着密切的关系。总之,本文主要研究了金属有机骨架材料和金属/金属有机骨架材料型固载催化剂的催化性能,详细考察了活性金属离子、金属有机骨架载体以及不同的反应条件对其催化性能的影响。通过对本课题的研究,较系统地了解了金属有机骨架材料的催化性能,对开发新型非均相催化剂有重要意义。更多还原

【Abstract】 Metal–organic frameworks （MOFs or Metallo-organic molecular sieve） are zeolite analogues with self-organization active centres, high apparent surface areas, geometrically well-defined structure and selective uptake of small molecules. Owing to these unique characteristics, MOFs are promising materials for sensor application, gas storage, catalysis and energy storage. At present, the mumber of catalytic studies using MOFs as the catalysts is limited. In this paper, various prepared MOFs, such as Cu₃（BTC）₂, ZIF-68, ZIF-60, ZIF-61, ZIF-62 were prepared and characterized by XRD, N₂ adsorption, ICP and SEM. And their catalytic performance as catalysts or catalyst supports was investigated in different reactions.1) Preparation, characterization and catalytic performance of Cu₃（BTC）₂Cu₃（BTC）₂ was prepared under different temperatures and used as catalysts for benzyl alcohol oxidation. The catalytic results show that the preparation tempreture have great influence on the catalytic oxidation activity. Cu₃（BTC）₂ synthesized under 383K exhibits much higher catalytic activity than Cu₃（BTC）₂ synthesized under 423K. The lower synthesis temperature can avoide the formation of Cu2O resulted from reduction of the Cu²⁺ ions.Cu₃（BTC）₂ synthesized at 383K could effectively catalyze benzyl alcohol oxidation and exhibited higher catalytic activity than Cu（II）-exchanged zeolite Y under the identical reaction conditions. The natures of reaction solvents had great influence on the catalytic activity and stability of Cu₃（BTC）₂. The XRD and SEM results showed that a structural and morphological change was observed during the reaction, but the reused catalyst still kept its original catalytic activity and even had higher activity than that of the fresh sample in acetone solvent.2) Preparation, characterization and catalytic performance of M/Cu₃（BTC）₂ （M= Cr,Pd,Mn and Co）Cu₃（BTC）₂ was utilized as support for preparing supported metal catalysts. The catalytic results of the prepared M/Cu₃（BTC）₂ in benzyl alcohol oxidation showed that the properties of metal ions had great influence on the benzyl alcohol oxidation activity. Among the selected metal ions, Cr/Cu₃（BTC）₂ exhibited the highest catalytic activity, while Pd/Cu₃（BTC）₂ exhibited the lowest activity.In order to investigate the catalytic performance of this new class of porous materials thoroughly, Pd/Cu₃（BTC）₂ was used as catalysts for styrene hydrogenation. XRD measurement indicated the structure of Cu₃（BTC）₂ was partly destroyed in the reduction process of Pd/Cu₃（BTC）₂, which resulted in lower catalytic hydrogenation activity. 3)Preparation, characterization and catalytic performance of Pd/ZIF-68ZIF-68 was selected as support for preparing Pd/ZIF-68. The catalytic hydrogenation results showed that Pd/ ZIF-68 could effectively catalyze styrene hydrogenation and exhibited high catalytic activity.a. The Pd loading have great influence on the catalytic hydrogenation activity, and with the increase of Pd loading, the catalytic hydrogenation activity also increased.b. Reaction conditions, including H2 pressure, reaction tempreture, reaction time had great influence on the catalytic hydrogenation activity of the catalyst.c. Quinoline and thiophene acted as poison feed for investigating the sufur and nitrogen resistance of catalyst Pd/ZIF-68. The catalytic hydrogenation tests showed that Pd/ZIF-68 has higher nitrogen resistance, because of the large mount of nitrogen on the framework.4)Preparation, characterization and catalytic performance of Pd/ZIFs（ZIFs= ZIF-68 , ZIF-60, ZIF-61 and ZIF-62）ZIFs, including ZIF-68、ZIF-60、ZIF-61 and ZIF-62 were used as supports for preparing Pd supported catalysts. The styrene catalytic hydrogenation tests showed that the catalytic hydrogenation activity of the catalysts was also related to the support structures and composition.In a summary, this paper is mainly concentrated on catalytic properties of MOFs as catalyst and catalyst support. From above research, we acquired comprehensive and systematic knowledge about catalytic properties of MOFs, which is very helpful for development and design of novel catalysts.更多还原