催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (9): 1145-1150.DOI: 10.3724/SP.J.1088.2010.00139

• 研究论文 • 上一篇    下一篇

费托合成 Fe基催化剂中铁物相与活性的关系

定明月 1,2, 杨勇 2, 相宏伟 2, 李永旺 2   

  1. 1中国科学院广州能源研究所可再生能源和天然气水合物重点实验室, 广东广州 510640 2中国科学院山西煤炭化学研究所煤转化国家重点实验室, 山西太原 030001
  • 收稿日期:2010-09-30 出版日期:2010-09-30 发布日期:2014-01-25

Relationship between Iron Phase and Activity of Iron-Based Fischer-Tropsch Synthesis Catalyst

DING Mingyue1,2,*, YANG Yong2, XIANG Hongwei2, LI Yongwang2   

  1. 1Key Laboratory of Renewable Energy and Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, Guangdong, China 2State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Shanxi, China
  • Received:2010-09-30 Online:2010-09-30 Published:2014-01-25

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1292

被引次数

37

摘要： 采用连续共沉淀和喷雾干燥相结合的方法制备了微球形 Fe 基催化剂, 采用 N2 吸附-脱附、X 射线衍射和穆斯堡尔谱等手段, 考察了催化剂在不同还原条件下铁物相的转变, 并在浆态床反应器中评价了催化剂的费-托合成 (FTS) 反应性能. 结果表明, Fe 基催化剂在合成气气氛下首先从α-Fe2O3 转变为 Fe3O4, 然后转变为铁碳化物 (FexC); 还原压力的增大有利于 α-Fe2O3 向 Fe3O4 的转变, 而抑制 Fe3O4 向 FexC 的转变; 还原空速的增加则促进 Fe3O4 转变为 FexC. 催化剂的 FTS 反应活性随着催化剂中 Fe3O4 含量的增加而逐渐下降, 而随着 FexC 含量的增加而逐渐上升.

关键词: 费托合成, 铁基催化剂, 合成气, 氧化铁, 碳化铁

Abstract: A typical Fe-based catalyst for Fischer-Tropsch synthesis (FTS) was prepared by a combination method of continuous co-precipitation and spray-drying technology. The study was undertaken to investigate the iron phase transformation under different pretreatment conditions and the influence of phase structure on FTS activity of the catalyst in a stirred tank slurry reactor. N2 adsorption-desorption, X-ray diffraction, and Mössbauer effect spectroscopy were used to characterize the catalyst. It was found that α-Fe2O3 in the fresh catalyst was reduced first to Fe3O4 and then converted to iron carbides (FexC) in the syngas atmosphere. Increasing the reduction space velocity promoted the reduction and carburization of the catalyst. Higher reduction pressure facilitated the reduction of α-Fe2O3 to Fe3O4 but suppressed the carburization of magnetite. During FTS the catalytic activity decreased gradually with increasing magnetite content and decreasing iron carbide content.

Key words: Fischer-Tropsch synthesis, iron-based catalyst, syngas, iron oxide, iron carbide