Highly Active and Stable Ni鈥揝iO2 Prepared by a Complex-Decomposition Method for Pressurized Carbon Dioxide Reforming of Methane

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• 作者：Hua-Ping Ren ; Yong-Hong Song ; Qing-Qing Hao ; Zhong-Wen Liu ; Wei Wang ; Jian-Gang Chen ; Jinqiang Jiang ; Zhao-Tie Liu ; Zhengping Hao ; Jian Lu
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2014
• 出版时间：December 10, 2014
• 年：2014
• 卷：53
• 期：49
• 页码：19077-19086
• 全文大小：611K
• ISSN：1520-5045

文摘

A series of Ni鈥揝iO₂ catalysts was synthesized by the complex-decomposition method using different amino acids as complexing agents and fuels and nickel nitrate and tetraethoxysilane as precursors of Ni and SiO₂, respectively. For comparison, ammonium hydroxide and acetic acid were also used as complexing agents and fuels. Characterization by XRD, TEM, and N₂ adsorption鈥揹esorption at low temperature indicated that the structural and textural properties of the Ni鈥揝iO₂ catalysts were strongly dependent on the complexing agent used. The dispersion of metallic Ni was increased by optimizing the complexing agent used. As revealed from H₂-TPR patterns, Ni鈥揝iO₂ exhibited significantly different interactions between Ni and SiO₂, the extent of which was influenced by the complexing agent used. The Ni鈥揝iO₂ catalysts were comparatively evaluated for carbon dioxide reforming of methane (CDR) under the following conditions: CH₄/CO₂ = 1.0, T = 750 掳C, GHSV = 53200 mL路g^鈥?路h^鈥?, and P = 1.0 atm. The results indicate that the Ni鈥揝iO₂ materials prepared with glycine, alanine, serine, threonine, valine, and proline exhibited much higher activity and stability for CDR under atmospheric conditions than those prepared with lysine, acetic acid, and ammonium hydroxide. Moreover, the Ni鈥揝iO₂ material prepared with glycine was also tested at elevated pressures of 5.0 and 10.0 atm. The effect of pressure on the CDR performance was investigated. Importantly, a highly active and stable Ni鈥揝iO₂ material for pressurized CDR was obtained by tailoring the structure of Ni鈥揝iO₂ and adjusting the interactions between Ni and SiO₂ by selecting the complexing agent. Thus, the main factors determining catalyst activity and stability for CDR were clearly revealed.