CIESC Journal ›› 2016, Vol. 67 ›› Issue (2): 549-556.DOI: 10.11949/j.issn.0438-1157.20151251

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Effect of support basicity on iron-based catalysts for Fischer-Tropsch synthesis

ZHANG Jun, ZHANG Zhengpai, SU Junjie, FU Donglong, DAI Weiwei, LIU Da, XU Jing, HAN Yifan   

  1. State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
  • Received:2015-08-03 Revised:2015-10-13 Online:2016-02-05 Published:2016-02-05
  • Supported by:

    supported by the National Natural Science Foundation of China (21273070, 21576084).

载体碱性对Fe基催化剂费-托合成反应的影响

张俊, 张征湃, 苏俊杰, 付东龙, 戴薇薇, 刘达, 徐晶, 韩一帆   

  1. 华东理工大学化学工程联合国家重点实验室, 上海 200237
  • 通讯作者: 韩一帆
  • 基金资助:

    国家自然科学基金项目(21273070,21576084)。

Abstract:

Lower hydrocarbons are key building blocks in chemical industry. The Fischer-Tropsch synthesis has been considered as one of the most promising non-oil based routes for lower hydrocarbons production. Previous studies have demonstrated that the supports can greatly affect the product distribution. In this work, the effects of the base property of supports on the catalytic performance of different Fe-based catalysts (Fe20/AlPO4, Fe20/γ-Al2O3 and Fe20/MgAl2O4) were investigated. The results showed that, with the increase in support basicity, the chain growth probability (α value), the selectivity of C5+ hydrocarbons and the olefins/paraffin ratio increased. Moreover, by combining with the Raman and temperature programmed hydrogenation (TPH), it was found that the higher basicity of supports could lead to the less active carbon (absorptive and atomic carbon) and the more inactive carbon (graphitized carbon) formation. In addition, with the combination of other characterization, such as XRD, H2-TPR, CO2-TPR, the structure-performance relationship was constructed. The variation in electron-donating ability of the supports strongly affected the content of carbonaceous species on the catalyst surface and the metal-support interaction, thereby leading to the difference in catalytic activity and selectivity.

Key words: Fischer-Tropsch synthesis, syngas, catalysis, Fe-based catalysts, catalyst support, basicity, carbon specie

摘要:

低碳烃类化合物是化学工业中重要的有机原料,通过非石油路线由费-托反应(Fischer-Tropsch)制备低碳烃类具有巨大前景,载体对于费-托合成催化剂的反应产物分布具有重要影响。探究了载体碱性对负载型Fe 基催化剂在费-托合成反应中反应性能的影响。通过浸渍法制备了Fe20/AlPO4、Fe20/γ-Al2O3、Fe20/MgAl2O4 催化剂,考评结果表明,载体碱性越强,碳链增长概率(α值)越大,C5+选择性上升,烯烷比(O/P)增加。通过Raman 光谱和TPH 实验对由柠檬酸铁铵为前体煅烧后的催化剂表层碳物种进行分析表明,载体碱性越强,催化剂表面碳石墨化程度越高,吸附碳数量越少。并依托XRD、H2-TPR、CO2-TPR 表征信息构建了不同碱性载体负载的Fe 基催化剂的构效关系,表明载体给电子能力的强弱引起催化剂表面碳物质含量和金属载体相互作用的差异,最终导致了催化活性和选择性的不同。

关键词: 费-托合成, 合成气, 催化, Fe 基催化剂, 催化剂载体, 碱性, 碳物种

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