【摘要】 用改性溶胶-凝胶法和共沉淀法分别制备了Zr-Ni-O-cp和Zr-Ni-O-sg催化剂并进行了比较,利用XRD,SEM和HRTEM观测催化剂的形貌和结构,通过H₂-TPR和O₂-TPD比较了催化剂的氧化还原性能和氧气吸脱附性能,采用XPS表征了催化剂表面元素价态和结构.结果表明:制备方法对Zr-Ni-O催化剂的物理化学性质有显著的影响,继而影响其ODHE催化性能;与Zr-Ni-O-cp相比,Zr-Ni-O-sg催化剂粒径较小,ZrO₂和NiO之间存在较强的相互作用,有较多的Zr⁴⁺取代晶格中的Ni²⁺,晶格氧移动性增加.因此,在乙烷氧化脱氢反应中,Zr-Ni-O-sg催化剂表现出更高的乙烯选择性和更好的抗乙烷裂解能力.更多还原

【Abstract】 Zr-Ni-O-cp and Zr-Ni-O-sg catalysts were prepared by modified sol-gel method and co-precipitation method respectively and compared. The morphology and structure of the catalysts were observed by XRD, SEM and HRTEM. The redox properties and oxygen adsorption of the catalysts were compared by H₂-TPR and O₂-TPD techniques. The valence and structure of the catalysts on the surface were characterized by XPS. The results showed that different preparation methods had a significant effect on the physicochemical properties of the Zr-Ni-O catalysts. Compared with Zr-Ni-O-cp sample prepared by co-precipitation method, Zr-Ni-O-sg prepared by modified sol-gel method showed smaller particle size and stronger interaction between ZrO₂ and NiO, resulted in the decreased redox and increased lattice oxygen mobility properties, and sequentially exhibited higher ethylene selectivity and better resistance ability to ethane cracking.更多还原