催化学报

催化学报 ›› 2008, Vol. 29 ›› Issue (5): 477-481.

• 研究论文 • 上一篇    下一篇

超高温焙烧的Ni/Al2O3对甲烷部分氧化反应的催化活性

陈永东,陈耀强,梅大江,张丽娟,董文萍,曹红岩,陈宏,龚茂初   

  1. 四川大学化学学院, 四川成都 610064
  • 收稿日期:2008-05-25 出版日期:2008-05-25 发布日期:2012-05-02

Partial Oxidation of Methane over Ni/Al2O3 Catalyst Calcined at Ultrahigh Temperatures

CHEN Yongdong, CHEN Yaoqiang, MEI Dajiang, ZHANG Lijuan, DONG Wenping, CAO Hongyan, CHEN Hong, GONG Maochu*   

  1. College of Chemistry, Sichuan University, Chengdu 610064, Sichuan, China
  • Received:2008-05-25 Online:2008-05-25 Published:2012-05-02

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摘要： 考察了超高温焙烧的Ni/Al2O3对甲烷部分氧化反应的催化性能,发现该催化剂经还原后对甲烷部分氧化反应表现出较高的催化活性. X射线衍射结果显示, Ni/Al2O3催化剂在超高温(1200～1400℃)下焙烧后生成了NiAl2O4, 且无相转移,进一步经950 ℃还原后催化剂中绝大部分Ni以单质Ni0形式存在. 透射电子显微镜测试结果表明,不同超高温焙烧的催化剂经950 ℃还原后Ni晶粒的大小无明显差异. 这说明超高温焙烧的Ni/Al2O3对甲烷部分氧化反应的高活性可归结为NiAl2O4的可还原性以及还原后Ni0相似的晶粒尺寸. 同时还发现,焙烧温度越高,生成的NiAl2O4的还原温度越高.

关键词: 镍, 氧化铝, 负载型催化剂, 超高温焙烧, 甲烷, 部分氧化, 还原

Abstract: The Ni/Al2O3 catalyst calcined at ultrahigh temperatures (1200-1400 ℃) was used in partial oxidation of methane (POM), and the Ni/Al2O3 catalyst retained high activity for POM after reduction. TheX-raydiffraction result indicated that NiAl2O4 was formed when the catalyst was calcined at ultrahigh temperatures, and there was no phase transition in the temperature range. After the catalyst was reduced by H2 at 950 ℃, most of Ni in the catalyst existed as Ni0, and the crystal size of Ni0 was similar, which was confirmed by transmission electron microscopy. The excellent performance of the Ni/Al2O3 catalyst calcined at ultrahigh temperatures for the POM reaction was attributed to both the reducibility of NiAl2O4 and the similar crystal size of Ni0. The higher the calcination temperature, the higher the reduction temperature for NiAl2O4.

Key words: nickel, alumina, supported catalyst, ultrahigh temperature calcination, methane, partial oxidation, reduction