论文部分内容阅读
采用等体积浸渍法结合NH3程序升温氮化技术,制备了一系列γ-Al2O3负载的Co/Mo金属氮化物催化剂。利用XRD、H2-TPR-MS和H2-TPSR-MS等手段,考察了Co/Mo金属氮化物催化剂及其氧化物前驱体的结构与表面性质;探讨了活性组分不同浸渍顺序制备的单、双金属氮化物的结构与表面性质差异;以NH3分解为探针反应考察了不同催化剂的反应性能差别。结果表明,活性组分的浸渍方式对催化剂的表面性质有重要的影响,共浸渍法制备的Co/Mo双金属氮化物由于其氧化物前驱体表面形成了CoMoO4相,有利于Co3Mo3N的生成。在NH3分解反应中,共浸渍法制备的Co/Mo双金属氮化物(0.56mol.g-1.h-1)比单金属氮化物和分步浸渍法制备的双金属氮化物具有更高的催化活性。
A series of γ-Al2O3 supported Co / Mo metal nitride catalysts were prepared by the same volume impregnation method combined with NH3 temperature-programmed nitriding process. The structure and surface properties of Co / Mo metal nitride catalysts and their oxide precursors were investigated by XRD, H2-TPR-MS and H2-TPSR-MS methods. The effects of single, The structure and surface properties of bimetallic nitrides are different. The decomposition reaction of NH3 is a probe reaction to investigate the difference in the reactivity of different catalysts. The results show that the impregnation mode of the active component has an important influence on the surface properties of the catalyst. Co / Mo bimetallic nitride prepared by the co-impregnation method is conducive to the formation of Co3Mo3N due to the CoMoO4 phase formed on the surface of the oxide precursor. In the NH3 decomposition reaction, Co / Mo bimetallic nitride (0.56 mol.g-1.h-1) prepared by co-impregnation method has a higher content than bimetallic nitride prepared by single metal nitridation and stepwise impregnation Catalytic activity.