镁铁镍复合氧化物的制备及其催化氨分解性能研究

Preparation of MgFeNi Composite Oxides and Its Catalytic Ammonia Decomposition Performance

采用溶胶凝胶法制备了不同计量比的镁铁镍复合金属氧化物,考查了其催化氨分解性能,结合一系列表征对催化剂构效关系进行了探讨。结果表明,复合金属氧化物催化活性明显高于传统的负载型非贵金属催化剂,Ni/Fe摩尔比的增加和碱土金属Mg的引入都有助于催化活性的增强,其中Mg_(0.2)Ni_(0.2)O_(n)在600℃时即达到96.9%的氨转化率。基于溶胶凝胶法制备复合金属氧化物具有微观形貌均一以及表面各种元素均匀分布的特点是其高活性的重要原因。

MgFeNi composite oxides with different molar ratios were prepared by the sol-gel method,and their catalytic performance for ammonia decomposition was investigated.The structure-activity relationship of catalysts was discussed combined with a series of characterization.The results show that the catalytic activity of the composite metal oxides is signif-icantly higher than that of the traditional supported non-noble metal catalysts.The increase of the molar ratio of Ni/Fe and the introduction of alkaline earth metal Mg contribute to the enhancement of the catalytic activity,and Mg_(0.2)Ni_(0.2)O_(n) reaches 96.9% ammonia conversion at 600℃.The high activity of composite metal oxides prepared by sol-gel method is due to their homogeneous morphology and uniform distribution of various elements on the surface.