高等学校化学学报 ›› 2002, Vol. 23 ›› Issue (1): 87.

• 研究论文 • 上一篇    下一篇

Fe1-xO基氨合成催化剂的制备化学

刘化章, 李小年, 胡樟能, 岑亚青, 傅冠平   

  1. 浙江工业大学催化研究所, 浙江省多相催化重点实验室, 杭州 310014
  • 收稿日期:2001-01-28 出版日期:2002-01-24 发布日期:2002-01-24
  • 通讯作者: 刘化章(1942年出生),男,教授,博士生导师,从事合成氨催化剂研究.E-mail:cuihua@hz.zj.cn E-mail:cuihua@hz.zj.cn
  • 基金资助:

    国家自然科学基金(批准号:29706011);国家九五攻关项目(批准号:96-550-02-01)资助.

Preparation Chemistry of Fe1-xO Based Catalyst for Ammonia Synthesis

LIU Hua-Zhang, Li-Xiao-Nian, HU Zhang-Neng, CEN Ya-Qing, FU Guan-Ping   

  1. Catalysis Institute of Zhejiang University of Technology, Zhejiang Key Laboratory of Heterogeneous Catalysis, Hangzhou 310014, China
  • Received:2001-01-28 Online:2002-01-24 Published:2002-01-24

摘要: 采用高温熔融法制备了各类铁氧化物,用XRD分析了熔融过程中的物相变化,EOS考察了熔融体凝固-冷却速率对助催化剂分布的影响.结果表明,采用大气气氛中的高温熔融法不能制取Fe2O3和化学计量比的FeO,前者会发生分解反应,后者会发生歧化反应;在1.333≤n(O)/n(Fe)<1.38范围时,可以制取Fe3O4或非化学计量比的Fe3-yO4;在1.11<n(O)/n(Fe)<1.333范围时,可以制取Fe3O4和FeO的混合氧化物;在1.045<n(O)/n(Fe)<1.111范围,平均冷却速度大于20℃/min时,可以制取非化学计量比的氧化亚铁Fe1-xO,即维氏体.Fe1-xO基催化剂的制备必须采用物理熔融与化学反应相结合的工艺.凝固冷却速度对抑制氧化亚铁的氧化反应和歧化反应,保证助催化剂的均匀分布和晶粒度均有很大影响

关键词: 氨合成催化剂, Fe1-xO, 制备化学, 熔融法

Abstract: The preparation chemistry of iron catalyst for ammonia synthesis is studied by molten method and X-ray diffraction. The chemical reaction and the change of crystal phase of iron oxide during the molten procedure is investigated according to Fe-O equilibrium diagram. The effect of solidifying-cooling rate of molten materials on the distribution of the promoters is exposed. It is indicated that Fe 2O3 and stoichiometric ferrous oxide FeO is not able to be obtained by molten method at atmosphere; Fe3O4 or non stoichiometric magnetite Fe3-yO4 of n (O)/ n (Fe) in the range of 1.333-1.38 and the mixture oxide of Fe3O4 and FeOof n (O)/ n (Fe) in the range of 1.111-1.333 may be obtained by the same method ; but non-stoichiometric ferrous oxide expressed as Fe1- x O or Wustite of n (O)/ n (Fe) in the range of 1.045- 1.111 may be obtained only when the cooling rate of molten materials is more than 20 ℃/min by molten method at atmosphere. There are observable influences of the solidifying cooling rate on the inhibition of the oxidation reaction and the disproportionation of the ferrous oxide Fe1- xO and improvement of the distribution of the promoters.

Key words: Ammonia synthesis catalyst, Fe1-x O, Preparation chemistry, Molten method

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