物理化学学报 >> 2013, Vol. 29 >> Issue (11): 2475-2480.doi: 10.3866/PKU.WHXB201310101

材料物理化学 上一篇    

Pt/Fe双金属Fischer-Tropsch催化剂的设计、合成及表征

曹崇江1,2, 刘晓庚1, 鞠兴荣1, 陈晓荣3   

  1. 1 南京财经大学应用化学系, 南京 210046;
    2 伊利诺伊州大学化学工程系, 美国芝加哥 60607;
    3 南京工业大学化学与化工学院, 南京 210009
  • 收稿日期:2013-07-29 修回日期:2013-10-08 发布日期:2013-10-30
  • 通讯作者: 曹崇江 E-mail:ccj33@163.com
  • 基金资助:

    国家科技部支撑计划(2011BAD03B02)资助

Design, Synthesis and Characterization of Pt/Fe Bimetallic Fischer-Tropsch Catalyst

CAO Chong-Jiang1,2, LIU Xiao-Geng1, JU Xing-Rong1, CHEN Xiao-Rong3   

  1. 1 Department of Applied Catalysis, Nanjing University of Finance and Economics, Nanjing 210046, P. R. China;
    2 Department of Chemical Engineering, University of Illinois, Chicago, IL 60607, USA;
    3 College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009, P. R. China
  • Received:2013-07-29 Revised:2013-10-08 Published:2013-10-30
  • Contact: CAO Chong-Jiang E-mail:ccj33@163.com
  • Supported by:

    The project was supported by the National Key Technology R&D Program of the Ministry of Science and Technology, China (2011BAD03B02).

摘要:

利用强静电吸附(SEA)理论, 根据Fe2O3与SiO2表面不同的零电荷点(PZC), 将铂盐溶液pH值调控后浸渍在Fe2O3/SiO2的载体上, 制备出Pt/Fe 双金属Fischer-Tropsch (F-T)催化剂, 通过N2 吸脱附技术、X射线衍射(XRD)、扫描投射电镜(STEM)和X射线能量散射谱(EDS)对催化剂的结构、形貌及组成进行表征. 结果表明浸渍过程中PtCl62-离子定向选择性地吸附在Fe2O3表面, 而非SiO2表面. 与传统浸渍(IW)法制备的催化剂比较, Pt与Fe紧密结合在一起, 还原后形成高度分散均一的纳米颗粒, 粒径尺寸在2 nm左右. 以F-T合成反应作为模型反应对催化活性进行表征, 强静电吸附法合成的催化剂表现出优异的催化性能, 反应进行150 h 后CO转化率仍保持在51%以上.

关键词: 强静电吸附, 催化剂, 费托合成, 氧化铁, 氧化硅

Abstract:

An efficient method for preparing highly dispersed bimetallic catalysts is described based on the different Point Zero Charges of Fe2O3 and SiO2. The strong electrostatic adsorption (SEA) technique was applied to the preparation of Pt-promoted Fe/SiO2 by driving the Pt precursor onto the Fe2O3 phase instead of the silica support. Characterization of the samples was carried out using N2 adsorptiondesorption, X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), and energy dispersive X-ray spectroscopy (EDS). The results showed that the SEA method can control the uptake of Pt onto the transition metal oxide instead of silica, forming tight coupling between the Pt and transition metal after reduction. Compared with the incipient wetness (IW) method, the SEA technique produced more intimately designed bimetallic particles with small, uniform distribution after reduction. The particle size is about 2 nm. From Fischer-Tropsch (F-T) reaction, the catalyst using SEA shows higher F-T activity and stability. The conversion is more than 51% after 150 h on the stream.

Key words: Strong electrostatic adsorption, Catalyst, Fischer-Tropsch synthesis, Iron oxide, Silica