Structural and Kinetics Understanding of Support Effects in Pd-Catalyzed Semi-Hydrogenation of Acetylene

• 作者: Yueqiang Cao Xiaohu Ge Yurou Li Rui Si Zhijun Sui Jinghong Zhou Xuezhi Duan Xinggui Zhou
• 来源期刊: 工程（英文）
• 年，卷（期）: 2021,（1）
• 所属期刊栏目: Frontiers of Chemical Engineering-Article
• 页码范围: 103-110
• 页数: 8页
• 语种: 英文

摘要

In this study,the support effects on the Pd-catalyzed semi-hydrogenation of acetylene have been inves-tigated from the structural and kinetic perspectives.According to the results of kinetic analysis and X-ray photoelectron spectroscopy,hydrogen temperature-programmed reduction,temperature-programmed hydride decomposition,and in situ X-ray diffraction measurements,using carbon nanotubes as support for Pd nanocatalysts with various sizes instead of α-Al2O3 decreases the Pd0 3d binding energy and sup-presses the formation of undesirable palladium hydride species,thus increasing the ethylene yield.Furthermore,X-ray absorption spectroscopy,high-resolution transmission electron microscopy,and C2H4 temperature-programmed desorption studies combined with density-functional theory calculations reveal the existence of a unique Pd local environment,containing subsurface carbon atoms,that produces positive geometric effects on the acetylene conversion reaction.Therefore,tailoring the Pd local environ-ment and electronic properties represents an effective strategy for the fabrication and design of highly active and selective Pd semi-hydrogenation catalysts.