Adsorption of H2 and CO on Iron-based Catalysts for Fischer-Tropsch Synthesis

The adsorption properties of CO and H2 on iron-based catalyst with addition of Zr and Ni were investigated using temperature programmed desorption process. It was found that on the carburized iron-based catalysts, molecular state and dissociative state CO existed together. The addition of Zr was preferential for the molecular state adsorption of CO on iron-based catalyst and the presence of Ni was beneficial to the dissociative adsorption of CO. On H2 reduced catalysts, hydrogen mainly adsorbs on the surface iron sites and surface oxide sites. On CO reduced catalysts, hydrogen probably existed as the most stable CH and OH species. The addition of Zr was not benefit to the dissociative adsorption of hydrogen on iron-based catalyst and the presence of Ni was preferential for the dissociative adsorption of hydrogen.

Authors:

• Weixin Qian
• Haitao Zhang
• Hongfang Ma
• Yongdi Liu
• Weiyong Ying
• Dingye Fang

Keywords:

• adsorption
• Fischer-Tropsch synthesis
• iron-based catalysts

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