Zr基MOF负载纳米Pd的制备及其催化性质研究

发布时间：2018-03-17 00:24

本文选题：Zr-MOF　切入点：Pd纳米颗粒　出处：《浙江工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：最近十年,金属-有机框架(Metal-Organic Frameworks,MOFs)作为一种新兴的多孔材料,引起了材料学家的广泛关注。一方面,MOFs的规整有序纳米尺寸的孔道能提供独特的微反应器,另一方面,MOFs纳微晶格表面常悬挂着有机配体,对金属具有很强的吸附作用。因此,MOFs是一种非常好的固载金属纳米催化剂的载体。Zr基MOFs是由Zr4+金属离子簇合物次级构筑单元与有机刚性配体配位组装形成的多孔材料。相对其他MOFs,其具有高的化学稳定性。贵金属纳米颗粒因其量子尺寸效应,常表现出良好的催化活性。Pd纳米颗粒是一种高效催化剂,但其价格昂贵,参与均相反应不易回收,故选择MOF负载得到高度分散的Pd纳米颗粒,既能降低成本,又能回收。本文中,采用浸渍法选择Zr-MOF材料(DUT-67、UiO-66-NH2)以及衍生的ZrO2作为载体材料制备三种不同的负载型Pd纳米催化剂。采用一系列表征手段对其进行表征,其结构表征可知,Pd纳米颗粒能高度分散在Zr-MOF框架中,且尺寸分布均匀,展示出很好的限域效应。催化性质测试表明:1)Pd/DUT-67在硝基苯加氢反应和Suzuki耦合反应中均有很好催化性能。在硝基苯加氢反应中,当温度达到60oC时,在2MPa H2的条件下反应3h,转化率达到99%。在Suzuki耦合反应中,反应条件以乙醇和水为混合溶剂,K2CO3为碱,温度为60oC,反应1h,能实现反应物的完全转换。2)Pd/UiO-66-NH2在CO催化氧化反应中的催化剂性能研究表明,当Pd的负载量分别为0.3%、0.5%以及1.0%时,CO氧化反应的T50分别为160 oC、165 oC和170 oC,T100均为180 oC。3)Pd/ZrO2-NH2在CO催化氧化中随温度升高均能实现CO的完全转换。在600 oC、700 oC以及800 oC下焙烧得到的ZrO2负载Pd的T100分别170 oC、160 oC和180 oC,而1.0%Pd/ZrO2-A和1.0%Pd/ZrO2-P分别为220 oC和200 oC。
[Abstract]:In the last decade, Metal-Organic frameworks (MOFs), as a new porous material, have attracted extensive attention of materials scientists. On the one hand, the well-ordered nanometer-sized pores of MOFs can provide unique microreactors. On the other hand, organic ligands are often suspended on the surface of MOFs nanocrystalline lattice. Therefore, MOFs is a very good carrier for supported metal nanocatalysts. Zr-based MOFs is composed of Zr4 metal ion cluster secondary building units and organic rigid ligands. Materials. Higher chemical stability than other MOFs. Noble metal nanoparticles due to their quantum size effects, Pd nanoparticles often show good catalytic activity, but they are expensive and difficult to recover in homogeneous reactions. Therefore, choosing MOF loaded to obtain highly dispersed PD nanoparticles can reduce the cost. In this paper, three different kinds of supported PD nanocatalysts were prepared by dipping method, Zr-MOF material (DUT-67UiO-66-NH2) and derivative ZrO2 were used as carrier materials, and were characterized by a series of characterization methods. The structure characterization shows that the Pd nanoparticles can be highly dispersed in the Zr-MOF framework, and the size distribution is uniform. The catalytic properties test showed that the catalytic properties of 1% Pd / DUT-67 were very good in the hydrogenation of nitrobenzene and the coupling reaction of Suzuki. In the hydrogenation of nitrobenzene, when the temperature reached 60oC, Under the condition of 2 MPA H2 for 3 h, the conversion reached 99%. In the Suzuki coupling reaction, the reaction conditions were ethanol and water as the mixed solvent K _ 2CO _ 3 as the base. When the reaction temperature is 60oC and the reaction time is 1h, the catalyst performance of PD / UiO-66-NH2 can be realized in CO catalytic oxidation reaction. The T50 of CO oxidation reaction was 160oC 165oC and 170oC T100 180 oC.3)Pd/ZrO2-NH2 respectively when PD loading was 0.3wt% and 1.0% respectively. The complete conversion of CO was achieved by calcination at 600oC 700oC and 800oC respectively during CO catalytic oxidation. The T100 of PD loaded on PD is 170oC and 180oC, respectively, while the 1.0 Pd-ZrO2-A and 1.0Pd-ZrO2-P are 220oC and 200oC, respectively.
【学位授予单位】：浙江工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;O643.36

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